Shorter Contributions to 

Paleontology and Stratigraphy 

Edited by Ellis L. Yochelson 

U.S. GEOLOGICAL SURVEY BULLETIN 1664 
DEPARTMENT OF THE INTERIOR 

DONALD PAUL HODEL, Secretary 

U.S. GEOLOGICAL SURVEY 

Dallas L. Peck, Director 

UNITED STATES GOVERNMENT PRINTING OFFICE: 1987 

For sale by the Books and Open-File Reports Section, U.S. Geological Survey, 

Federal Center, Box 25425, Denver, CO 80225 

Library of Congress Cataloging-in-Publication Data 

Main entry under title: 

Shorter contributions to paleontology and stratigraphy. 

(U.S. Geological Survey bulletin ; 1664-A, B, C) 

Supt. of Docs. no.: I 19.3:1664-A, B, C 

Contents: The Miocene Pillarian and Newportian (molluscan) 

stages of Washington and Oregon and their usefulness in 

correlations from Alaska to California I by Ellen j. Moore 

and Warren 0. Addicott-A new species of lsogramma 

(Brachiopoda) from the Pennsylvanian of north-central 

Texas I by Bruce R. Wardlaw, David E. Schindel, and Ellis 

L. Yochelson-Middle and Upper Triassic marine 

Ostracoda from the Shublik Formation, northeastern 

Alaska I by I.G. Sohn. 

1. Mollusks, Fossil-Addresses, essays, lectures. 2. Brachiopoda, 

Fossil-Addresses, essays, lectures. 3. Ostracoda, FossilAddresses, essays, lectures, 4. Paleontology-United 

States-Addresses, essays, lectures. 5. Geology, Stratigraphic-Addresses, essays, lectures. I. Yochelson, Ellis 

Leon, 1928- II. Moore, Ellen james. The Miocene 

Pillarian and Newportian (molluscan) stages of Washington and Oregon and their usefulness in correlations from 

Alaska to California. 1987. Ill. Wardlaw, Bruce R. A new 

species of lsogramma (Brachiopoda) from the Pennsylvanian of north-central Texas. 1987. IV. Sohn, I. G. (Israel 

Gregory), 1911- . Middle and Upper Triassic marine 

Ostracoda from the Shublik Formation, northeastern 

Alaska. 198 7. V Series. 

QE75.B9 no. 1664-A,B,C 557.3 s 85-600292 

[QE801] [564] 
CONTENTS 

CHAPTER A 

The Miocene Pillarian and Newportian (Molluscan) Stages of 

Washington and Oregon and Their Usefulness in Correlations From 

Alaska to California Al 

Ellen 1. Moore and Warren 0. Addicott 

CHAPTER B 

A New Species of Isogramma (Brachiopoda) From the Pennsylvanian of 

North-Central Texas Bl 

Bruce R. Wardlaw, David E. Schindel, and Ellis L. Yochelson 

CHAPTER C 

Middle and Upper Triassic Marine Ostracoda From the Shublik Formation, Northeastern Alaska Cl 

I. G. Sohn 

Contents Ill 

CHAPTER A 

The Miocene Pillarian and Newportian 

(Molluscan) Stages of Washington and Oregon 

and Their Usefulness in Correlations From 

Alaska to California 

By ELLEN J. MOORE and WARREN 0. ADDICOTT 

U.S. GEOLOGICAL SURVEY BULLETIN 1664 

Shorter Contributions to Paleontology and Stratigraphy 

CONTENTS 

Abstract Al 

Introduction Al 

Acknowledgments A2 

Pillarian and Newportian Stages A2 

Rationale of molluscan distribution and correlation A4 

Alaska A4 

Formations assigned to the Pillarian Stage A4 

Formations assigned to the Newportian Stage A7 

British Columbia A 7 

Washington A 7 

Formations assigned to the Pillarian Stage A 7 

Formations assigned to the Newportian Stage A 7 

Oregon A7 

Formations assigned to the Pillarian Stage A 7 

Formations assigned to the Newportian Stage AS 

California AS 

Formations assigned to the Pillarian Stage AS 

Formations assigned to the Newportian Stage AS 

Baja California AS 

Peak occurrences of key species A9 

References cited All 

Abbreviations Al3 

Fossil localities Al3 

PLATES 

[Plates follow Fossil Localities] 

1. Patinopecten, Molopophorus, Vertipecten 

2. Patinopecten, Bruclarkia, Vertipecten 

3. Patinopecten, Katherinella, Epitonium, Anomalocardia, Macoma, Lucinoma, Securella, Musashia, Dosinia, Cyclocardia 

4. Vertipecten, Ficus, Musashia, Saccella, Patinopecten, Epitonium, Priscofusus 

FIGURES 

1. Map showing location of type areas of molluscan stages and geographic names referred to in text A2 

2. Chronostratigraphic position and correlation of the Miocene Pillarian and Newportian (molluscan) Stages A3 

TABLE 

1. Distribution of selected mollusks from the upper Oligocene to the middle 

Miocene AS 

Contents Ill 

The Miocene Pi llarian and Newportian 

(Molluscan) Stages of Washington and Oregon 

and Their Usefulness in Correlations From 

Alaska to California 

By Ellen J. Moore and Warren 0. Addicott 

Abstract 

Mollusks are common to abundant in shallow-water facies, 

which predominate in many geographically isolated Tertiary 

basins, and are reliable for correlation. The global cooling that 

began during middle Miocene (Newportian Stage, in part) and 

increased in intensity across the middle to late Miocene 

boundary (Newportian, in part, to Wishkahan Stage) strongly 

affected the usefulness of mollusks for correlating these stages 

from California to Alaska. The warming trend that peaked during the late early and early middle Miocene, however, allows 

good correlations between the "Temblor" Stage of California 

and the middle part of the Newportian Stage of the Pacific 

Northwest. Mollusks restricted to either the Pillarian or Newportian and those with first or last occurrences in either stage 

have helped to identify the two stages and to differentiate between them. Additional collecting and appraisal of faunas 

show that these molluscan stages can be further refined and 

divided on the basis of peak occurrences of molluscan species 

that are related, in part, to global changes in climate. 

Unnamed Miocene sediments at Coos Bay, Ore., are Newportian in age but probably somewhat older than the Astoria 

Formation in the Newport embayment, Oregon. The lower part 

of a section of unnamed Miocene sediments in northern California is Newportian in age, based on the occurrence of 

Molopophorus matthewi Etherington, and the upper part of the 

section is no younger than Newportian. 

INTRODUCTION 

The initial chronostratigraphic framework for the marine 

Cenozoic of the Western United States was proposed by 

Arnold (1906) for California. He used names of formations 

in the sense that we use our present stages and defined the 

biostratigraphic units mostly by distinctive invertebrate assemblages, principally pectinids. These units were refined 

and modified on the basis of mollusks by subsequent workers (Smith, 1912; Clark, 1921, 1929; Loel and Corey, 1932) 

who variously termed them "faunas," "formations," or 

"horizons." Kleinpell (1938) proposed Miocene benthic 

foraminiferal stages for California and reviewed the relations of the molluscan sequence to his stages. 

In contrast to California, Neogene strata are distributed 

less widely in Oregon, Washington, British Columbia, and 

Alaska, where marine basins, most extensive during the 

early and middle Miocene, consisted of isolated coastal 

embayments from southern Oregon to the Queen Charlotte 

Islands and the Gulf of Alaska (fig. 1). Weaver (1916a) 

proposed faunal zones for western Washington on the basis 

of molluscan faunas and key species and later correlated the 

Tertiary sequence of the Pacific Northwest with the California formations by using the existing formational names as 

stages (Weaver, 1942). 

In 1944, a basic framework for all Pacific Coast Cenozoic 

molluscan correlation was prepared under Weaver's chairmanship (Weaver and others, 1944). In that correlation 

scheme, Neogene stages were first used, and zonal index 

fossils were cited. These stages, however, were based primarily on type sections in California and were difficult to 

use in correlating within and beyond the Pacific Northwest. 

Previously, Schenck ( 1936) had proposed three biozones for 

Oregon and Washington on the basis of species of the 

bivalveAcila, and Durham (1944) proposed seven megafossil zones for northwestern Washington. These zones proved 

so useful for provincial correlation that they still are used 

today. 

For the Pacific Northwest, Addicott (1976b) proposed a 

series of six Neogene molluscan stages that have type sections in Washington and Oregon and correlated them with 

California benthic foraminiferal stages; later, he somewhat 

modified the ages of the molluscan stages (Addicott, 1981, 

1983). Armentrout (1975) proposed the late Eocene and 

early Oligocene Galvinian and Oligocene Matlockian (molluscan) Stages; to avoid conflict with the late Oligocene part 

of the Juanian (molluscan) Stage of Addicott (1976b), he 

(1977, 1981) subsequently revised the Matlockian to include only the early Oligocene. Using Durham's (1944) 

megafossil zones for the Oligocene, Addicott (1976b) also 

Miocene Pillarian and Newportian Stages of Washingto~ and Oregon Al 
ALASKA 

160o PENINSULA ~ C9G...,/. 

KODIAK~ (/ 0

/ -'~~'- = 

50° 

20° 

ISLAND 08-fo 

PACIFIC OCEAN 

VANCOUVER ISLAND 

PILLARIAN STAGE 

JUANIAN STAGE 

WISHKAHAN STAGE 

;-8~ 

s}J.s't~1 """ <'~ltJ. ·-1. <1sfu e 

Tillamook Bay f}Slt0 , 

N EWPORTIAN ST~Gu~na Bay • , .._- • / --y' Coos Bay Newport : 

Cape Blanco Ore / 9ofJ 1 

Eureka '· 

......._ I ; .......... , I 

~ 

I 

San Francisco ( 

Santa Cruz Mountains 

"VAQUEROS" STAGE 

"TEMBLOR" STAGE 

200 400 600 BOO KILOMETERS 

120° 

\ 

\ 

' ) 

-""): 

,, 

~f~"' ~/('()'· 

proposed new molluscan zones for his Miocene molluscan 

stages. These stages and zones, intended originally for 

provincial correlation, have been used to correlate these 

units with Tertiary units north to Alaska (Allison, 1978; 

Marincovich, 1983; Allison and Marincovich, 1981) and 

south to middle California (Moore, 1984). 

Armentrout and others (1984) have summarized the correlation of Cenozoic molluscan stages of Oregon and Washington with microfossil datum planes and with megaflora! 

and mammalian stages and radiometric dates. Poore and 

others ( 1981) have presented a biochronology standard for 

the Miocene of the Eastern Pacific by correlating planktic 

foraminifer, coccolith, and diatom zones with California 

molluscan stages. 

This paper focuses on the early Miocene Pillarian and the 

early and middle Miocene Newportian (molluscan) Stages 

proposed by Addicott ( 1976b) that have type sections in 

Washington and Oregon, respectively. These stages primarily are based on range zones of taxa, mostly endemic species. Some difficulty may be encountered, however, in distinguishing the Pillarian and Newportian Stages when the 

key zonal species Vertipecten fucanus (Dall) and 

Patinopecten propatulus (Conrad) are not present. Additional collecting and appraisal of faunas has led to the recognition of more molluscan species that serve to distinguish 

the Pillarian and Newportian Stages and also has led to 

distinguishing times of peak abundance for some species 

that permit subdivisions within a stage. 

ACKNOWLEDGMENTS 

We thank Gail H. Goedert for donating a specimen of 

Epitoniwn (Cirsotrema) clallamensis that she collected from 

the Nye Mudstone, James L. Goedert for collecting and 

donating specimens of Vertipecten fucanus from the Nye, 

and Parke D. Snavely, Jr.. for calling attention to a locality 

in the Nye Mudstone northeast of Newport from which 

Patinopecten oregonensis cancellosus was collected. We 

profited from discussions regarding this study with John A. 

Barron, Louie Marincovich. Jr., Kristin A. McDougalL and 

Parke D. Snavely, Jr., U.S. Geological Survey; Richard C. 

Allison, University of Alaska; and Weldon W. Rau. Washington Division of Mines and Geology. 

PILLARIAN AND NEWPORTIAN STAGES 

The Pillarian Stage (Addicott. 1976b) is defined in rocks 

which contain an inner sublittoral molluscan fauna and is of 

early Miocene age. The Clallam Formation. designated as 

the type section of the Pillarian. directly overlies the type 

section of the Juanian of late Oligocene and early Miocene 

Figure 1. Location of type areas of molluscan stages and geographic names referred to in text. 
age, and the lower boundary of the Pillarian is placed at the 

contact between the Twin River Formation and the overlying Clallam Formation. The Clallam Formation is not overlain by younger strata at its type section along the Strait of 

Juan de Fuca. Wash .. so the top of the Pillarian Stage could 

not be defined in that area. Therefore, the upper boundary 

stratotype was defined as the contact between the Nye Mudstone and the overlying Astoria Formation exposed south of 

Yaquina Bay. Ore. (fig. I). The Pillarian originally was 

dated as late early Miocene but subsequently has been revised to include the early early Miocene (Allison. 1977. 

1978: Addicott. 1983 ). and this usage is here accepted. 

Mollusks recognized by Addicott ( 1976b) as restricted to 

the Pillarian Stage in the Eastern Pacific include the pelecypods Vertipecten .fitcanus (Oall), Mytilus n. sp. aff. 

M. tichanm·itchi Makiyama of Allison and Addicott ( 1976), 

and Macoma optira (Yokoyama). and the gastropods 

Prisn~fltsus aff. P. geniculus (Conrad) of Moore ( 1963) and 

Aforia tricarinata Addicott. Additional mollusks now 

known to be restricted to, or with their last occurrence in, 

the Pillarian are the pelecypods Acila (Acila) gettysburgensis (Reagan) and Anomalocardia carmanahensis (Clark) and 

the gastropod. Epitonium (Cirsotrema) clallamensis 

Durham. 

Age California 

M.Y. Benthic 

The Newportian Stage (fig. 1) is based on the molluscan 

fauna in the Astoria Formation in the Newport embayment 

on the coast of northwestern Oregon. Originally dated as 

middle Miocene, it subsequently has been revised (Addicott, 1977) to include the late early Miocene (fig. 2). The 

lower boundary is placed at the base of the Astoria Formation, best exposed in sea cliffs between Y aquina Head and 

Newport. Ore. The top of the Newportian is best defined in 

the Astoria Formation in southwestern Washington (Addicott. 1976b), where the upper part is conformably overlain 

by the Montesano Formation of Fowler ( 1965) that contains 

shallow-water molluscan assemblages referable to the late 

middle Miocene Wishkahan Stage (ftg. 2). Allison (1977, 

1978) revised the Wishkahan to include the late middle 

Miocene as well as the late Miocene, and this usage is here 

accepted. 

Mollusks recognized by Addicott ( 1976b) as restricted in 

stratigraphic occurrence to the Newportian Stage include the 

pelecypods Aequipecten andersoni clemonensis (Etherington), Mytilus (Plicatomytilus) middendorffi Grewingk, 

Patinopecten propatulus (Conrad), and Saccella amelga 

Moore and the gastropods Acteon boulderanus Etherington, 

Antillophos posunculensis (Anderson and Martin), Chlorostoma pacificum (Anderson and Martin), "Nassarius" 

Pacific Northwest 

B. p Epoch Foraminiferal Molluscan Molluscan Molluscan 

Stage Stage Stage Zone 

II c 

ca 

·c: 

"Margaritan" Pati nopecten 

E .J::. Wishkahan 0 oregonensis 

Middle Qj ~ 0 

Miocene 

-15- • • • I] • • • • c • Pati nopect~n 

• 

I~ "Temblor" Newportian propatulus • 

• 

c 

ca 

·u; 

Cll 

-20- Early (.) 

:1 

Miocene ca 

(/) 

V ertipecten Pillarian fuca nus 

"Vaqueros" 

• Liracassis 

-25- Late Juanian a pta Oligocene 

Figure 2. Chronostratigraphic position and correlation of the Miocene Pillarian and Newportian (molluscan) Stages. Vertical 

dashes indicate possible extensions of stages. 

Miocene Pillarian and Newportian Stages of Washington and Oregon A3 
arnoldi (Anderson), Nucella aff. N. lima Gmelin of Moore 

(1963), Opalia williamsoni (Anderson and Martin), Priscofusus medialis (Conrad), Spirotropis washingtonensis 

Etherington, and Trophon kernensis Anderson. Other mollusks now known to be restricted to the Newportian are the 

pelecypods Macoma flagleri Etherington, Spisula (Mactromeris) selbyensis Packard, and Yoldia carnerosensis 

Clark and the gastropods Cancellaria ocoyana Addicott, 

Molopophorus anglonanus (Anderson), Molopophorus mattewi Etherington, Nucella packi (Clark), and Olivella 

ischnon Keen. 

In addition to the mollusks known to be restricted to either 

the Pillarian or the Newportian Stages, the combination of 

first and last occurrences of species further identifies the two 

stages, and some of these ranges are shown graphically in 

table 1. The Newportian Stage can be correlated with the 

"Temblor" Stage of California (Weaver and others, 1944) 

on the basis of the cooccurrence of molluscan species. Correlation of the Pillarian Stage with the "Vaqueros" Stage of 

California (Weaver and others, 1944) has not been feasible 

using mollusks. The predominately tropical and subtropical 

molluscan fauna of the "Vaqueros," from the northwardtransported west side of the San Andreas fault, has not been 

recognized in Washington or Oregon. 

RATIONALE OF MOLLUSCAN DISTRIBUTION 

AND CORRELATION 

Past discussions of climate, as interpreted by molluscan 

distribution and by most other biologic groups, were 

premised on two assumptions: temperature tolerances of 

species remained the same through time and the continents 

were fixed. Tectonic reconstructions have shown that fragments of the Pacific coastal areas of North America have 

been transported long distances along strike-slip faults and 

that terranes from distant areas to the south and east have 

been accreted to the coast of North America at various 

times. In addition, the cooccurrence of both subtropical and 

cold-water molluscan genera within the same stratigraphic 

interval, especially in Alaska, indicates that some parameters of past molluscan distributions do not match those of 

today; for example, in the Narrow Cape Formation of Newportian age on Kodiak Island, the warm-water genera 

Dosinia s. s., Securella, and Anadara s. s. are found with 

genera of cool-water aspect, such as Neptunea and Mya. 

Nevertheless, some patterns of distribution that are related 

to climatic events seem evident. 

Post-Eocene steepening of latitudinal climatic gradients 

and the accompanying development of restricted molluscan 

faunal provinces isolated the faunas of the Pacific Northwest 

from California for prolonged periods of time. Warming 

events interrupted this pattern, most noticeably in the late 

early and early middle Miocene, when the warm temperate 

and subtropical to tropical molluscan faunas of California 

reached as far north as the western part of the Gulf of 

A4 Shorter Contributions to Paleontology and Stratigraphy 

Alaska. This Miocene warming and its wide dispersal of 

species allows both tentative and definite assignment of 

formations to the Newportian Stage from Alaska south to 

California ("Temblor" Stage). The occurrence in the Newportian of genera such as the pelecypods Dosinia s. s. and 

Securella and the gastropod Ficus, genera now living in 

subtropical to tropical regions, indicates that, during the 

early middle Miocene, the ocean as far north as the Alaska 

Peninsula may have been much warmer than it is today. 

Warming was not sufficient during the older Pillarian Stage, 

however, to make definite ties between the Pacific northwest and California, although the cephalopod Aturia flourished during the late Juanian and early Pillarian. 

The global warming trend across the early and middle 

Miocene boundary (Woodruff and others, 1981) allowed the 

dispersal of subtropical to tropical molluscan genera as far 

north as the western part of the Gulf of Alaska (Addicott, 

1969). As stated above, warm-water genera are found in the 

Narrow Cape Formation of Newportian age on Kodiak Island (Allison, 1978). However, in the northeastern Gulf of 

Alaska, the middle Miocene faunas in the lower part of the 

Yakataga Formation (Addicott, 1969) and in the Topsy Formation (Marincovich, 1979) include no warm-water genera. 

Thus, the Topsy and Yakataga faunas presumably coincide 

with or postdate the major cooling event. 

The distribution in Oregon of the warm-water genus 

Dosinia s. s. is particularly interesting. It is extremely common in the dredgings of unnamed Miocene sediment in the 

Coos Bay channel, where more than 200 specimens were 

collected in a short period of time (Moore, 1963). Yet 

Dosinia s. s. has not been collected from the Astoria Formation in the Newport area, about 140 kilometers north of 

Coos Bay, despite its record from the Gulf of Alaska in the 

Newportian. We believe, therefore, that the maximum 

warming trend occurred in the early Newportian and that the 

unnamed Miocene sediment at the Coos Bay channel is 

older than the Astoria Formation at Newport, although still 

assigned to the Newportian on the basis of Mytilus (Plicatomytilus) middendorfi Grewingk. The upper part of the Astoria Formation in southwestern Washington is the youngest 

unit assigned to the Newportian. 

ALASKA 

Formations Assigned to the Pillarian Stage 

The uppermost part of the Poul Creek Formation, in the 

northeastern Gulf of Alaska, was assigned to the Pillarian 

(Addicott, 1977) on the basis of the occurrence of the zonal 

fossil Vertipecten fucanus and associated mollusks such as 

Acila (Acila) gettysburgensis, which are not known to occur 

in younger strata (Allison, 1978). The lower part of the 

Yakataga Formation on Kayak Island, also in the northeastem Gulf of Alaska, was assigned to the Pillarian on the basis 

of the cooccurrence of the pelecypod A. (A.) gettysburgensis 
Table 1. Distribution of selected mollusks from the upper Oligocene to the middle Miocene 

[x, present; ?, possibly present] 

Subseries ___________________________________ _ 

Molluscan stage ______________________________ _ 

Molluscan zone _______________________________ _ 

Pelecypods: 

Acharax dalli (Clark) ___________________________ _ 

Acharax ventricosa (Conrad) ______________________ _ 

Acila (Acila) gettysburgensis (Reagan) ________________ _ 

Acila (Truncacila) conrad£ (Dall) ___________________ _ 

Ac~·la (Truncacila) muta (Clark) ____________________ _ 

Acila (Truncacila) packardi (Clark) __________________ _ 

Aequipecten andersoni clemonensis (Etherington) ________ _ 

Anadara (Anadara) devincta (Conrad) ________________ _ 

Anomalocardia carmanahensis (Clark) ________________ _ 

Clinocardium n. sp. aff. C. nuttalli (Conrad) of Moore (1963) __ Conchocele bisecta (Conrad) ______________________ _ 

Cyclocardia castor (Dall) ________________________ _ 

Cyclocardia subtenta (Conrad) _____________________ _ 

Dosinia (Dosinia) whitney£ (Gabb) __________________ _ 

Katherinella (Katherinella) angustifrons (Conrad) ________ _ 

Litorhadia astoriana (Henderson) ___________________ _ 

Lucinoma acutilineata (Conrad) ____________________ _ 

Lucinoma hannibal£ (Clark) ______________________ _ 

lvfacoma alban·a (Conrad) ________________________ _ 

Macoma arctata (Conrad) ________________________ _ 

Macoma astori (Dall) ___________________________ _ 

Macoma jlagleri Etherington - - - - - - - - - - - - - - - - - - - - - - - Macoma optiva Yokoyama _______________________ _ 

Macoma secta (Conrad) _________________________ _ 

Macoma sookensis (Clark and Arnold) _______________ _ 

Macoma twinensis Clark ________________________ _ 

Mytilus (Plicatomytilus) middendorffi Grewingk _________ _ 

Mytilus n. sp. aff. M. tichanovitchi Makiyama of Allison and 

Addicott (1976) ____________________________ _ 

Panopea abrupta (Conrad) _______________________ _ 

Panopea ramonensis (Clark) ______________________ _ 

Patinopecten oregonensis cancellosus Moore ___________ _ 

Patinopecten propatulus (Conrad) __________________ _ 

Saccella amelga Moore __________________________ _ 

Sac cella calkins£ Moore _________________________ _ 

Securella enszfera (Dall) _________________________ _ 

So/amen snavelyi Addicott _______________________ _ 

Spisula (Hemimactra) hannibal£ Clark ________________ _ 

Spisula (Mactromeris) albaria (Conrad) _______________ _ 

Spisula (Mactromeris) selbyensis Packard _____________ _ 

Spisula (Mactromeris) sookensis Clark and Arnold - - - - - - - - Tellina emacerata Conrad _______________________ _ 

Vertipecten fucanus (Dall) _______________________ _ 

Yoldia carnerosensis Clark _______________________ _ 

Yoldia clallamensis Reagan _______________________ _ 

Upper Oligocene 

and lower Miocene 

Juanian 

Liracassis 

apt a 

X 

X 

X 

X 

X 

X 

X 

X 

? 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

Lower 

Miocene 

Pillarian 

Vertipecten 

fucanus 

X 

X 

X 

X 

X 

X 

? 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

Lower and 

middle Miocene 

Newportian 

Pat~·nopecten 

propatulus 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

? 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

Miocene Pillarian and Newportian Stages of Washington and Oregon A5 
Table 1. Distribution of selected mollusks from the upper Oligocene to the middle Miocene-Continued 

Subseries ___________________________________ _ Upper Oligocene Lower Lower and 

and lower Miocene Miocene middle Miocene 

Molluscan stage ______________________________ _ Juanian Pillarian Newportian 

Molluscan zone _______________________________ _ L£racass£s Vertz"pecten Patinopecten 

a pta fuca nus propatulus 

Pelecypods-Continued 

Yoldia supramontereyensis Arnold __________________ _ X 

Yoldia tenuissz"ma Clark _________________________ _ X 

Gastropods: 

Acteon boulderanus Etherington ____________________ _ X 

Aforia tricarz"nata Addicott _______________________ _ X 

Ancistrolepis fz"mgoederti Moore ____________________ _ X 

Ancistrolepsis rearensis (Clark) ____________________ _ X X 

Antillophos posunculensis (Anderson and Martin) _________ _ X 

Bruclarkia oregonensis (Conrad) ____________________ _ X X 

Bruclark£a yaquinana (Anderson and Martin) ___________ _ X X 

Cancellaria ocoyana Addicott _____________________ _ X 

Cancellaria oregonensis Conrad ____________________ _ X 

Cancellaria weaveri Etherington ____________________ _ X X 

Cancellaria wynoochensis Weaver ___________________ _ X 

Chlorostoma pacificum (Anderson and Martin) __________ _ X 

Crepidula rostra/is (Conrad) ______________________ _ X 

Epitonium ( Cirsotrema) clallamensis Durham ___________ _ X X 

Ficus modesta (Conrad) _________________________ _ X X 

Liracassis apta (Tegland) ________________________ _ X 

Liracassis petrosa (Conrad) _______________________ _ X 

Megasurcula wynoocheensis (Weaver) ________________ _ ? X 

Molopophorus anglonanus (Anderson) ________________ _ X 

Molopophorus matthewi Etherington _________________ _ X 

Molopophorus newcombei (Merriam) _________________ _ X 

Musashia (Miopleiona) indurata (Conrad) ______________ _ X X 

Musashia (Nipponomelon) shikami Moore ______________ _ X 

"Nassarius" arnoldi (Anderson) ____________________ _ X 

"Nassarius" lincolnensis (Anderson and Martin) _________ _ X 

Neve rita famesae Moore _________________________ _ X X X 

Nucella aff. N. lima Gmelin of Moore (1963) ____________ _ X 

Nucella packi (Clark) ___________________________ _ X 

Olivella ischnon Keen __________________________ _ X 

Opalia williamsoni (Anderson and Martin) _____________ _ X 

Priscofusus aff. P. geniculus (Conrad) of Moore (1963) _____ _ X 

Priscofusus medialis (Conrad) _____________________ _ X 

Priscofusus slipensis Addicott _____________________ _ X X 

Semicassis pyshtensis Addicott ____________________ _ X 

Spirotropis washingtonensis Etherington ______________ _ x· 

Trophon kernensis Anderson ______________________ _ X 

Trophosycon clallamensis (Weaver~ _________________ _ X ? 

Turritella (Idaella?) oregonensis (Conrad~ _____________ _ X X 

Turritella (Idaella) yaquinana Addicott _______________ _ X X 

Xenoturris antiselli (Anderson and Martin) ____________ _ X X 

Cephalopod: 

Aturia angustata (Conrad) _______________________ _ X X 

A6 Shorter Contributions to Paleontology and Stratigraphy 
with foraminifers of Saucesian or Relizian age (Allison, 

1978). 

Formations Assigned to the Newportian Stage 

The type Narrow Cape Formation on Kodiak Island was 

assigned to the Newportian on the basis of the occurrence 

throughout the section (Allison, 1978) of Mytilus (Plicatomytilus) middendorffi Grewingk, a mytilid that occurs in the 

Newportian as far south as central California. The Unga 

Conglomerate Member of the Bear Lake Formation on the 

Alaska Peninsula is believed to be late Newportian in age on 

the basis of the combined ranges of a few molluscan taxa 

(Allison, 1978). Strata near the base of the Yakataga Formation at Yakataga Reef, Alaska, were assigned to the Newportian on the basis of the presence of M acoma arctata 

(Conrad), not known to occur in strata younger than Newportian, and the genus Lituyapecten, not known to occur in 

strata older than Newportian (Addicott, 1974). On the basis 

of overlapping ranges ofPillarian and Newportian mollusks, 

the Topsy Formation in the Lituya district was inferred to be 

of Newportian age (Marincovich, 1979). 

BRITISH COLUMBIA 

Strata that can be assigned to either the Pillarian or Newportian Stages have not been found in British Columbia. 

Division D of Jeletzky (1954, 1973) and the type Sooke 

Formation are assigned to the late Oligocene and the earliest 

Miocene Juanian Stage. 

WASHINGTON 

Formations Assigned to the Pillarian Stage 

The Clallam Formation, exposed in northernmost Washington along the Strait of Juan de Fuca, was designated the 

type section for the Pillarian Stage (Addicott, 1976b). The 

zonal fossil, Vertipectenfucanus, is the most characteristic 

mollusk in faunal assemblages from the Clallam. The Hoh 

Formation of Weaver ( 1915), just to the south on the westem side of the Olympic Mountains, also was assigned to the 

Pillarian on the basis of the occurrence of Vertipecten fucanus. Strata assigned to the Astoria Formation in Wahkiakum and Pacific Counties, Wash. (Wolfe and McKee, 

1972) include faunas characteristic of the Pillarian and the 

Newportian Stages. On the basis of the occurrence of pectinid zonal fossils and on first and last occurrences of associated mollusks, unit I (Wolfe and McKee, 1972) in the 

lower part of the Astoria Formation in southwestern Washington was assigned to the Pillarian (Addicott, 1976b). 

Formations Assigned to the Newportian Stage 

The Astoria Formation in the southern part of the Montesano quadrangle east of Grays Harbor and units II and III in 

the Astoria Formation in the Grays River quadrangle, 

Wahkiakum County (Wolfe and McKee, 1972), were assigned to the Newportian on the basis of the zonal fossil 

Patinopecten propatulus and associated mollusks and benthic foraminifers (Addicott, 1976b). 

OREGON 

Formations Assigned to the Pillarian Stage 

Vertipecten fucanus and Patinopecten propatulus, zonal 

fossils from the Pillarian and Newportian Stages, respectively, are present in the Dana collection from the type area 

of the Astoria Formation in Astoria, Ore. (Conrad, 1849). 

The original exposures of the Astoria Formation are now 

covered by the city of Astoria, thereby prohibiting verification of the occurrence. Other mollusks from the type Astoria 

Formation that have their last occurrence in the Pillarian 

(Addicott, 1976c) are Acila (Acila) gettysburgensis (Reagan) and Aturia angustata (Conrad) (Addicott, 1976b; 

1976c). On the basis of the available data, the lower part of 

the type Astoria Formation is assumed to be Pillarian in age. 

In the Astoria Formation in northwestern Oregon, some 

exposures contain meager and poorly preserved molluscan 

faunas that seem to be late Pillarian or early Newportian in 

age, but no definite assignment can be made. Specimens 

believed to represent Patinopecten oregonesis cancellosus 

Moore have been found in some of these collections. This 

species originally was described from the unnamed sediment at the Coos Bay channel, but it has since been found 

in the uppermost part of the Nye Mudstone at the northeast 

side of the Newport embayment. Future study likely will 

show that this pectinid is restricted to the late Pillarian and 

early Newportian. It is not known to cooccur with Vertipecten fucanus or Patinopecten propatulus. Dosinia 

(Dosinia) whitneyi (Gabb) also occurs in the unnamed sediment at the Coos Bay channel and has been found in southem California in the Wygal Sandstone Member of the 

Temblor Formation [previously known as the Phacoides 

Sand Member of Stinemeyer and others (1959)] (Addicott, 

1973), the San Ramon Sandstone (Clark, 1918), and the 

"Sobrante Sandstone" (Lutz, 1951). All but possibly the 

"Sobrante Sandstone" are pre-Newportian in age. Loel and 

Corey (1932) have called attention to the abundance of the 

pelecypod Dosinia s. s. in the "Vaqueros" Stage, which is 

represented by a subtropical to tropical fauna. Today, 

Dosinia s.s. lives no farther north than Baja California. The 

post-Oligocene warming trend reached a peak probably in 

the late early and early middle Miocene. This was followed 

Miocene Pillarian and Newportian Stages of Washington and Oregon A7 
during the middle Miocene by global cooling that intensified 

across the middle and late Miocene boundary (Barron, 

1985). In northwestern Oregon, Dosinia s. s. whitneyi has 

been found in the Astoria Formation of Newportian age and 

in the unnamed Miocene sediment at Coos Bay channel, 

where it is exceptionally abundant and occurs with Mytilus 

(Plicatomytilus) middendorfi, which is considered to be restricted to the Newportian Stage (Moore, 1963). It has not 

been found in the Newportian part of the Astoria Formation 

in the Newport area, however, and may have become extinct 

in Washington, Oregon, and Alaska at the end of the early 

Newportian. Dosinia (D.) whitneyi also is found associated 

with Patinopecten oregonensis cancellosus rather than with 

Patinopecten propatulus. Thus, the unnamed Miocene sediments at Coos Bay may represent the earliest part of the 

Newportian Stage, a time when Newportian mollusks were 

first evolving. In northwestern Oregon, Dosinia (D.) whitneyi is found in the Angora Peak Member of the Astoria 

Formation of Niem ( 197 5) associated with Mytilus ( P.) middenforffi. 

All but the lowermost part of the Nye Mudstone in the 

Newport embayment was assigned to the Pillarian (Addicott, 1976b). This assignment is based on the occurrence of 

Vertipectenfucanus in the Nye Mudstone south of Newport 

and on associated mollusks and benthic foraminifers. The 

occurrence of Patinopecten oregonensis cancellosus in the 

uppermost Nye northeast of Newport may indicate that the 

uppermost part of the Nye is early Newportian. On the basis 

of Vertipecten fucanus and associated mollusks, the upper 

part of the Y aquina Formation south of Newport is assigned 

to the Pillarian. 

Formations Assigned to the Newportian Stage 

The upper part of the type Astoria Formation at Astoria is 

assigned to the Newportian on the basis of Patinopecten 

propatulus and associated mollusks (Conrad, 1848, 1849; 

Moore, 1963). Exposures of the Astoria Formation on Big 

Creek east of Astoria and near Cannon Beach to the south 

also are assigned to the Newportian (Addicott, 1976b), as is 

the Astoria Formation in the Cathlamet, Saddle Mountain, 

Cape Foulweather, and Yaquina quadrangles in northwestem Oregon (Moore, 1963). The sandstone of Floras Lake at 

Cape Blanco is assigned to the Newportian (Addicott, 1983) 

on the basis of the gastropods Molopophorus matthewi 

Etherington and "Nassarius" arnoldi (Anderson) and the 

pelecypods Mytilus (P.) middendorffi Grewingk and Macoma flagleri, all restricted to the Newportian, and on the 

cooccurrence of other species with longer ranges. 

CALIFORNIA 

The Pillarian Stage is coeval with the upper part of the 

"Vaqueros" Stage, and the Newportian Stage is coeval with 

the "Temblor" Stage, both of California. 

A8 Shorter Contributions to Paleontology and Stratigraphy 

Formations Assigned to the Pillarian Stage 

Vertipecten fucanus occurs in the Jewett Sand and in the 

upper part of the Olcese Formation in southern California 

which can be correlated with the Pillarian. The Juanian and 

Pillarian gastropod Epitonium (Cirsostrema) clallamensis 

Durham also is found in the Jewett Sand. As stated above, 

the tropical and subtropical fauna of the "Vaqueros" Stage 

did not reach as far north as Oregon, and correlations between Oregon and California are difficult. 

Formations Assigned to the Newportian Stage 

The "Temblor" Stage of California is characterized by the 

restricted stratigraphic occurrence of molluscan species that 

also are restricted to the Newportian Stage. Species common to the two stages and restricted to them include the 

pelecypods Mytilus (Plicatomytilus) middendor.ffi Grewingk 

and Patinopecten propatulus (Conrad) and the gastropods 

"Nassarius" arnoldi (Anderson), Crepidula rostra/is (Conrad), Antillophos posunculensis (Anderson and Martin), 

Opalia williamsoni (Anderson and Martin), and Olivella 

ischnon Keen (Addicott, 1972). Thus, the Buttonbed Sand 

Member of the Temblor Formation of Stinemeyer and others 

(1959) as well as the Round Mountain Silt in southern California can be correlated with the Newportian (Addicott, 

1970). 

The pelecypods Acila (Truncacila) conradi (Dall), Delectopecten peckhami (Gabb), Katherinella (Katherinella) angustifrons (Conrad), Securella ensifera (Dall), Tel/ina 

emacerata Conrad, and Thracia trapezoides (Conrad) and 

the gastropods Ficus modesta Conrad, Megasurcula 

wynoocheensis (Weaver), and Molopophorus matthewi 

Etherington were discovered recently in unnamed Miocene 

sediments in northern California on the south flank of the 

Coast Range in the Garberville area southeast of Eureka 

(Barry Roth, oral commun., 1984). All of these mollusks 

except Acila (T.) conradi and Molopophorus matthewi are 

found in both the Pillarian and the Newportian. One locality 

that is near the base of the section (Julie Menack, oral 

commun., 1984) yielded the gastropod M olopophorus 

matthewi, restricted to the Newportian, and these unnamed 

sediments are assigned here to the Newportian. 

BAJA CALl FORN lA 

Miocene molluscan faunas in Baja California have been 

poorly known until recent years (Minch and others, 1970; 

Smith, 1984), and precise age determinations based on faunal analyses and potassium-argon dating are much less precise than those in California. Currently, the Rosarito Beach 

Formation is assigned to the middle Miocene (Minch and 

others, 1970), the Isidro Formation to the earliest Miocene 

to early middle . Miocene, the Tortugas Formation to the 

early middle Miocene, and the San Ignacio Formation to the 

late middle Miocene (Smith, 1984). 
PEAK OCCURRENCES OF KEY SPECIES 

Patinopecten propatulus (Conrad) is the zonal fossil of 

the Newportian Stage, whereas Vertipecten fucanus (Dall) 

identifies the Pillarian. Vertipecten is differentiated easily 

from species of Patinopecten when the left valve is preserved (pl. 1, fig. 5; pl. 4, figs. 9, 11) but not as easily 

distinguished when only the right valve is preserved (pl. 1, 

fig. 1; pl. 2, fig. 9; pl. 4. fig. 1). The left valve ofV.fucanus 

has three ribs raised above the others: the middle rib and the 

third rib on either side of the middle. The left valve of P. 

propatulus has evenly spaced, low, rounded ribs (pl. 1, 

fig. 4). The right-valve auricles of V. fucanus (pl. 1, fig. 9) 

are relatively much larger than those of P. propatulus (pl. 1, 

fig. 1; pl. 3, fig. 6); on V. fucanus, the length of the auricles 

is more than half the width of the valves, whereas on P. 

propatulus the auricles are less than half the width of the 

valves. The ribbing on right valves of V. fucanus is much 

more irregular than that on P. propatulus; many specimens 

have one or more irregular ribs in the middle part of the disk 

(pl. 1, fig. 10), and most specimens have a widening and 

deepening of the medial interspace that corresponds to the 

strongly raised opposing rib on the left valve. 

Patinopecten propatulus is abundant in units II and III in 

the Astoria Formation of southwestern Washington (Wolfe 

and McKee, 1972) and in the Astoria Formation in the 

Newport embayment, and its peak occurrence is in the early 

middle Miocene. 

Patinopecten oregonensis cancellosus Moore, originally 

described from the unnamed Miocene sediment of the Coos 

Bay channeL Oregon (Moore, 1963), has been found in 

abundance in the upper part of the Nye Mudstone in the 

Newport embayment northeast of Newport, Ore., and it has 

been recognized in a few collections of Newportian age 

from northwestern Oregon. Its peak occurrence is in the late 

early Miocene part of the Pillarian. Patinopecten oregonensis cancellosus may have been confused in the past with P. 

propatulus and V. fucanus. The right valve of P. oregonensis cancellosus (pl. 2, figs. 1, 4) has regularly spaced, 

strongly undercut ribs that look like railroad ties in cross 

section (pl. 4, fig. 5) and no strongly raised ribs on the left 

valve (pl. 2, fig. 5; pl. 3, fig. 1). These characters differentiate it from V. fucanus. Patinopecten oregonensis cancellosus differs from P. propatulus by having a heavier shell 

and by both valves having fewer ribs that are higher and 

more undercut than those on P. propatulus, which has a low 

rib profile (pl. 1, fig. 7). 

Anadara (Anadara) devincta (Conrad) ranges from the 

late Pillarian to the Wishkahan Stages. The occurrence in 

the Pillarian is based on the rare occurrence of this species 

in the Nye Mudstone. It is not found in other stratigraphic 

units assigned to the Pillarian. Abundant in the Astoria 

Formation in the Newport embayment, this species was not 

found in the unnamed Miocene sediment dredged from Coos 

Bay channel. We believe that this indicates that the Astoria 

Formation at Newport is younger than the unnamed sediment at Coos Bay channel and further suggests that the peak 

abundance of A. (A.) devincta was in the middle 

Newportian. In California, A. (A.) devincta has been collected in the Sobrante and Briones Sandstones and in the 

Temblor Formation. 

Dosinia (D.) whitneyi (Gabb), when found in abundance, 

probably indicates an early Newportian age. This species 

occurs in Alaska in the type Narrow Cape Formation (Louie 

Marincovich, Jr., written commun., 1978), in Oregon, 

rarely in the Angora Peak Member of the Astoria Formation 

of Niem (1975), and abundantly in the unnamed Miocene 

sediment dredged from Coos Bay channel (pl. 3, fig. 13) 

and in California in the San Ramon Formation (Gabb, 1866; 

Stewart, 1930), the Wygal Sandstone Member of the Temblor Formation (Addicott, 1973), and in the "Sobrante 

Sandstone" of Lutz (1951). Dosinia (D.) whitneyi has not 

been found in the Newportian Astoria Formation in the 

Newport area. 

Securella ensifera (Dall) ranges from the Pillarian Stage 

through the Newportian. Although the species is present in 

the Newportian and common in the unnamed Miocene sediment of Coos Bay, Ore., its peak abundance is in the 

Pillarian; for example, it is one of the most abundant 

bivalves in the Clallam Formation in Washington (Addicott, 

1976a) and is common in the Nye Mudstone south of Newport, Ore. (pl. 3, fig. 9). 

Anomalocardia carmanahensis (Clark) ranges from the 

Juanian Stage through the Pillarian and is not found in the 

Newportian. It is distinct and easily differentiated from the 

more common Pillarian and Newportian chionid Securella 

ensifera (pl. 3, fig. 9). Anomalocardia carmanahensis is 

differentiated on the basis of its very thick and rounded 

concentric ridges (pl. 3, figs. 4, 5) that disappear near the 

anterior margin. Originally described from the Sooke Formation of British Columbia, this species has been collected 

from strata of Pillarian age in northwestern Oregon. 

Bruclarkia yaquinana (Anderson and Martin) and Bruclarkia oregonensis (Conrad) sometimes cooccur in the Pillarian Clallam Formation, but typical B. yaquinana is the 

most common. Typical B. oregonensis occurs almost exclusively at the top of the Clallam, and B. yaquinana occurs at 

or near the base (Addicott, 1976a). In the Kern River area 

of California, B. yaquinana is restricted in occurrence to the 

basal early Miocene part of the Jewett Sand. Bruclarkia 

yaquinana occurs in Washington in the Clallam Formation, 

in Oregon in the Astoria Formation and in the Nye Mudstone, and in California in the Jewett Sand and Painted Rock 

Sandstone Member of the Vaqueros Formation, both of 

early Miocene age, and in the basal part of the Saltos Shale 

Member of the Monterey Shale of Hill and others (1958), 

also of early Miocene age. The peak occurrence of B. 

yaquinana is in the middle early Miocene. Bruclarkia oregonensis occurs in Washington in the Clallam Formation 

and the Hoh Formation of Weaver (1915), in Oregon in the 

Miocene Pillarian and Newportian Stages of Washington and Oregon A9 
Scappoose and Astoria Formations and in the sandstone of 

Flores Lake (Addicott, 1983), and in California in the Sobrante(?) Sandstone, the Oursan Sandstone, lower and upper parts of the Olcese Sand, the Buttonbed Sandstone 

Member of the Temblor Formation, the Twisselmann Sandstone Member of the Monterey Formation of Heikkila and 

MacLeod ( 1951), unnamed Miocene sediment in the Santa 

Cruz Mountains, and the Saltos Shale Member of the Monterey Shale of Hill and others (1958). These two species 

occur together in the Clallam Formation of Washington and 

the Astoria Formation of Oregon and possibly in the Saltos 

Shale Member of the Monterey Shale, California, of Hill 

and others (1958), although B. yaquinana is restricted to the 

basal part. Transitional specimens (pl. 2, fig. 3) that link the 

two species have been found in the Astoria Formation in 

Oregon (Moore, 1963) and in the Clallam Formation in 

Washington (Addicott, 1976a). Typical B. oregonensis 

(pl. 2, figs. 2, 8) differs from typical B. yaquinana (pl. 2, 

figs. 6, 7) by having uniformly fine sculpture through all 

stages of growth, whereas B. yaquinana has four or five 

coarsely noded spiral cords on the body whorl. The peak 

abundance of B. yaquinana seems to be in the Pillarian, 

possibly continuing into the early Newportian, and the peak 

abundance of B. oregonensis is in the middle Newportian. 

Epitonium (Cirsotrema) clallamensis Durham ranges 

from the Juanian to the Pillarian Stages. It occurs in the 

upper part of the Poul Creek Formation of the Gulf of 

Alaska (Kanno, 1971), in the Sooke Formation in British 

Columbia (Durham, 1937), in the Clallam Formation in 

Washington, in the Nye Mudstone south of Newport, Ore. 

(pl. 3, fig. 3), and in the Jewett Sand (pl. 3, fig. 11; pl. 4, 

figs. 7, 10) in central California (Addicott, 1970). It also has 

been found in the Miocene Macoma optiva molluscan zone 

in the Tochilinski sequence of western Kamchatka 

(Gladenkov and Sinelnikova, 1984). The species is distinguished by the heavy bladelike to blocky costae and by the 

three to nine low, broad spiral ribs that cross the costae and 

form nodes on the central part of the whorl. 

Musashia (Nipponomelon) shikami Moore (pl. 3, fig. 12; 

pl. 4, fig. 3) first appeared in the early Miocene within the 

upper part of the Juanian Stage (Moore, 1984). This species 

has a wide distribution: in Alaska in the upper part of the 

Poul Creek Formation; in Washington in the Clallam Formation, the upper part of the Pysht Formation of the Twin 

River Group, and the upper part of the Lincoln Creek Formation; in Oregon in the Nye Mudstone (Howe, 1922; 

Moore, 1984); and in California in the Freeman-Jewett silt 

of Matthews (1955) and the Vaqueros Formation. Musashia 

( N.) shikami lacks the deeply impressed, channeled suture 

and strongly twisted, keellike ribs of Musashia (Miopleiona) indurata (Conrad), the Newportian volutid (pl. 3, 

fig. 15). 

Priscofusus aff. P. geniculus (Conrad) of Moore (1963) 

has been found in the lower part of the Clallam Formation 

A 1 0 Shorter Contributions to Paleontology and Stratigraphy 

in Washington and in the Nye Mudstone south of Newport, 

Ore. (pl. 4, fig. 8). It occurs in strata of presumed Pillarian 

age in northwestern Oregon and is assumed to be restricted 

to the Pillarian Stage. 

Molopophorus matthewi Etherington and Molopophorus 

anglonanus (Anderson) are restricted to the Newportian. 

Molopophorus matthewi (pl. 1, figs. 6, 8) has a smooth, 

rounded body whorl, whereas M. anglonanus (pl. 1, figs. 2, 

3) has a sharply angulated and noded body whorl profile. 

The cephalopod Aturia angustata (Conrad) is thought to 

have become extinct at the end of the early Miocene (late 

Pillarian). This extinction may be related to the global cooling that began in the middle Miocene. The species is doubtfully identified from the Clallam Formation of Washington 

(Addicott, 1976a) and is positively identified from the Pysht 

Member of the Twin River Group. It is extremely abundant 

in the southwesternmost Washington (Moore, 1984) at the 

top of the Lincoln Creek Formation of late Juanian (earliest 

Miocene) age and has been found in Oregon in the Newport 

embayment in the Nye Mudstone of Pillarian age. 

Aturia angustata is very rare in the California Miocene 

with only two specimens reported from the upper part of the 

"Vaqueros" Stage of Addicott (1972). The scarcity of 

Aturia in California in the early Miocene cannot be explained by cooling because the "Vaqueros" molluscan 

fauna is subtropical to tropical. Nautilus, the only living 

relative of Aturia, lives today in the South Pacific, mostly 

near islands with shallow water near shore and nearby steep 

continental shelves where depths drop off rapidly to 600 

meters or more. Aturia probably lived in similar geographic 

areas in the early Miocene, and its scarcity in California may 

be related to the absence of habitats with shallow water close 

to deep water. In addition, other ''Vaqueros'' faunas generally represent shallower water than the common depth for 

Aturia of 100-350 meters (Moore, 1984). Nevertheless, the 

worldwide extinction of Aturia probably is related to the 

middle Miocene global cooling event. 

Some of the mollusks common to the Pillarian and Newportian Stages, and about equally abundant in both, are 

Ficus modesta (Conrad) (pl. 4, fig. 2), Cyclocardia subtenta (Conrad) (pl. 3, fig. 16), Lucinoma acutilineata (Conrad) (pl. 3, fig. 8), Katherinella (Katherinella) angustifrons 

(Conrad) (pl. 3, figs. 2, 10, 14), Macoma albaria (Conrad) 

(pl. 3, fig. 7), and Saccella amelga Moore (pl. 4, figs. 4, 6). 

On the basis of peak occurrences of key species, we 

believe that the unnamed Miocene sediments at Coos Bay, 

Ore., and the type section of the Narrow Cape Formation, 

on Kodiak Island, Alaska, represent the late early Miocene 

part of the Newportian and that units II and III of the Astoria 

Formation in southwestern Washington (Wolfe and McKee, 

1972) and the Astoria Formation in the Newport embayment, Oregon, represent the early middle Miocene part of 

the Newportian. 
REFERENCES CITED 

Addicott, W. 0., 1969, Tertiary climatic change in the marginal 

northeastern Pacific Ocean: Science, v. 165, p. 583-586, 3 

figs. 

---1970, Miocene gastropods and biostratigraphy of the Kern 

River area, California: U.S. Geological Survey Professional 

Paper 642, 174 p., 21 pls. 

---1972, Provincial middle and late Tertiary molluscan stages, 

Temblor Range, California, in The Pacific Coast Miocene 

Biostratigraphic Symposium: Society of Economic Paleontologists and Mineralogists, Pacific Section, Bakersfield, Calif., 

47th, Proceedings, v. 1, 1972, p. 1-26, pls. 1-4. 

---1973, Oligocene molluscan biostratigraphy and paleontology of the lower part of the type Temblor Formation, California: U.S. Geological Survey Professional Paper 791, 48 p., 

9 pis. 

---1974, Giant pectinids of the eastern North Pacific margin: 

significance in Neogene zoogeography and chronostratigraphy: Journal of Paleontology, v. 48, no. 1, p. 180-194,2 pls. 

---1976a, Molluscan paleontology of the lower Miocene Clallam Formation. northwestern Washington: U.S. Geological 

Survey Professional Paper 976, 44 p., 9 pls., 10 figs. 

---1976b, Neogene moJluscan stages of Oregon and Washington, in Fritsche, A. A., ed., The Neogene Symposium; selected papers on paleontology, sedimentology, petrology, tectonics, and geologic history of the Pacific Coast of North 

America: Society of Economic Paleontologists and Mineralogists, Pacific Section, San Francisco, Calif., 1976, p. 95-

115, 5 pls., 6 figs. 

---1976c, On the significance of the bivalve Acila gettysburgensis (Reagan) in the middle Tertiary chronostratigraphy of 

the Pacific coast: The Veliger, v. 19, no. 2, p. 121-124, 3 

figs. 

---1977, Neogene chronostratigraphy of nearshore marine 

basins of the eastern North Pacific in Saito, Tsanemasa, and 

Ujiie, Hiroshi, eds., Proceedings of the First International 

Congress on Pacific Neogene Stratigraphy, Tokyo, 1976, Science Council of Japan: Tokyo. Kaiyo Shuppan Co., p. 151-

175. 

---1981, Significance of pectinids in Tertiary biochronology 

of the Pacific Northwest, in Armentrout, J. M., ed., Pacific 

Northwest Cenozoic biostratigraphy: Geological Society of 

America Special Paper 194, p. 17-37. 

---1983, Biostratigraphy of the marine Neogene sequence at 

Cape Blanco, southwestern Oregon: U.S. Geological Survey 

Professional Paper 774-G, p. Gl-G20, 3 pls. 

Allison, R. C., 1977, Late Oligocene through Pleistocene molluscan faunas in the Gulf of Alaska region, in Saito, Tsanemasa, 

and Ujiie. Hiroshi. eds., Proceedings of the First International 

Congress of Pacific Neogene Stratigraphy, Tokyo, 1976, Science Council of Japan: Tokyo, Kaiyo Shuppan Co., p. 313-

316. 

---1978, Late Oligocene through Pleistocene molluscan faunas in the Gulf of Alaska region: The Veliger, v. 21, no. 2, 

p. 171-188, 2 figs .. 2 tbls. 

Allison, R. C., and Addicott, W. 0., 1976, The North Pacific 

Miocene record of Mytilus ( Plicatomytilus), a new subgenus 

(Bivalvia): U.S. Geological Survey Professional Paper 962, 

21 p .. 3 pis. 

Allison, R. C.. and Marincovich, Louie, Jr., 1981 [1982], A late 

Oligocene or earliest Miocene molluscan fauna from Sitkinak 

Island, Alaska: U.S. Geological Survey Professional Paper 

1233, 11 p., 3 pis., 3 figs., 6 tbls. 

Armentrout, J. M., 1975, Molluscan biostratigraphy of the Lincoln Creek Formation, southwest Washington, in Weaver, 

D. W., Hornaday, G. R., and Tipton, Ann, eds., Paleogene 

symposium and selected technical papers; Conference on Future Energy Horizons of the Pacific Coast: Society of Economic Paleontology and Mineralogy, Pacific Section, Long 

Beach, Calif., 1975, p. 14-48, 7 figs. 

---1977, Cenozoic molluscan stages of Oregon and Washington: Geological Society of America Abstracts with Programs, 

v. 9, no. 7, p. 882-883. 

---1981, Correlation and ages of Cenozoic chronostratigraphic units in Oregon and Washington, in Armentrout, 

J. M., ed., Pacific Northwest Cenozoic biostratigraphy: Geological Society of America Special Paper 184, p. 137-148. 

Armentrout, J. M., Echols, R. J., and Ingle, J. C. Jr., 1984, 

Neogene biostratigraphic-chronostratigraphic scale for the 

northeastern Pacific margin, in Ikebe, Nobuo, and Tsuchi, 

Ryuichi, eds., Pacific Neogene datum planes; contributions to 

biostratigraphy and chronology: Tokyo, Japan, University of 

Tokyo Press, p. 171-177, 2 figs. 

Arnold, Ralph, 1906, The Tertiary and Quaternary pectens of 

California: U.S. Geological Survey Professional Paper 4 7, 

246 p. 53 pis., 2 figs. 

Barron, J. A., 1985, Diatom paleoceanography and paleoclimatology of the central and eastern equatorial Pacific between 18 

and 6.2 Ma: Initial Reports of the Deep Sea Drilling Project, 

v. 85, p. 935-345, 7 figs. 

Clark, B. L. , 1918, The San Lorenzo series of middle California: 

University of California Publications, Department of Geology 

Bulletin, v. 11, no. 2, p. 45-235, pis. 3-24. 

---1921, The marine Tertiary of the west coast of the United 

States-Its sequence, paleogeography, and the problems of 

correlation: Journal of Geology, v. 29, no. 7, p. 583-614, 12 

figs. 

---1929, Stratigraphy and faunal horizons of the Coast Ranges 

of California: Privately published, 30 p., 50 pis. (Ann Arbor, 

Mich., University Microfilms, Inc., 30 p., 50 pis.). 

Conrad, T. A. 1848, Fossil shells from Tertiary deposits on Columbia River, near Astoria: American Journal of Science, ser. 

2, v. 5, p. 432-433, 14 figs. (Reprinted in Dall, W. H., 1909, 

U.S. Geological Survey Professional Paper 59, p. 150-151). 

---1849, Fossils from northwestern America, in Dana, J. D., 

Geology: Philadelphia, Pa., U.S. Exploring Expedition*** 

1838-1842, under the command of Charles Wilkes, v. 10, 

appendix 1, p. 722-730, atlas, pls. 17-21. (Reprinted in 

Dall, W. H., 1909, U.S. Geological Survey Professional 

Paper 59, p. 152-157). 

Durham, J. W., 1937, Gastropods of the family Epitoniidae from 

Mesozoic and Cenozoic rocks of the west coast of North 

America, including one new species by F. E. Turner and one 

by R. A. Bramkamp: Journal of Paleontology, v. 11, no. 6, 

p. 479-512, pls. 56-57. 

---1944, Megafauna! zones of the Oligocene of northwestern 

Washington: University of California Publications, Department of Geological Sciences Bulletin, v. 27, no. 5, p. 101-

211, pis. 13-18. 

Miocene Pillarian and Newportian Stages of Washington and Oregon A 11 
Fowler, G. A., 1965, The stratigraphy, foraminifera, and paleoecology of the Montesano Formation Grays Harbor, County, 

Washington [abs., Los Angeles, University of Southern California Ph.D. dissertation]: Dissertation Abstracts, v. 26, 

p. 3245. 

Gabb, W. M., 1866, Tertiary invertebrate fossils: California Geological Survey, Paleontology, v. 2, Cretaceous and Tertiary 

fossils, sec. 1, pt. 1, p. 1-38, pis. 1-13. 

Gladenkov, Y. B., and Sinelnikova, V. N., 1984, Marine mollusks, in Menner, V. V., ed., Atlas fauny i flory neogenovykh otlozhenii Dal negro Vostoka [Atlas of faune and flora 

of the Neogene sediments of the Far East; Tochilinski key 

section of western Kamchatka] (in Russian): Academy of 

Sciences of the USSR Transactions, v. 385, p. 50-61. 

Heikkila, H. H., and MacLeod, G. M., 1951, Geology of Bitterwater Creek area, Kern County, California: California Division of Mines Special Report 6, 21 p. 

Hill, M. L., Carlson, S. A., and Dibblee, T. W., Jr., 1958, 

Stratigraphy of Cuyama Valley-Caliente Range area, California: American Association of Petroleum Geologists Bulletin, 

v. 42, no. 12, p. 2973-3000. 

Howe, H. V. W., 1922, The Miocene of Clatsop and Lincoln 

Counties, Oregon: Stanford, Calif., Stanford University 

Ph.D. dissertation, 286 p., 14 pls., 1 map. 

Jeletzky, J. A., 1954, Tertiary rocks of the Hesquiat-Nootka area, 

west coast of Vancouver Island, British Columbia: Geological 

Survey of Canada Paper 53-17, 65 p. 

---1973, Age and depositional environments of Tertiary rocks 

of Nootka Island, British Columbia: Canadian Journal of 

Earth Sciences, v. 10, no. 3, p. 331-365, 3 pis., 2 figs., 

2 tbls. 

Kanno, Saburo, 1971, Tertiary molluscan fauna from the Yakataga 

district and adjacent areas of southern Alaska: Palaeontological Society of Japan Special Paper 16, 154 p. 18 pls. 

Kleinpell, R. M., 1938, Miocene stratigraphy of California: Tulsa, 

Okla., American Association of Petroleum Geologists, 450 p. 

Loel, Wayne, and Corey, W. H., 1932, The Vaqueros Formation, 

lower Miocene of California; 1, Paleontology: University of 

California Publications, Department of Geological Sciences 

Bulletin, v. 22, no. 3, p. 31-411, pis. 4-65. 

Lutz, G. C., 1951, The Sobrante Sandstone: University of California Publications, Department of Geological Sciences Bulletin, v. 28, no. 13, p. 367-405, pls. 15-18, 3 figs. 

Marincovich, Louie, Jr., 1979 [1980], Miocene mollusks of the 

Topsy Formation, Lituya district, Gulf of Alaska Tertiary 

Province, Alaska: U.S. Geological Survey Professional Paper 

1125-C, 14 p., 30 figs. 

---1983, Molluscan paleontology, paleoecology, and North 

Pacific correlations of the Miocene Tachilni Formation, 

Alaska Peninsula, Alaska: Bulletins of American Paleontology, v. 84, no. 317, 155 p., 23 pis., 7 figs., 10 tbls. 

Matthews, J. F., Jr., 1955, Edison Groves area of Edison oil field: 

California Oil Fields, v. 41, no. 2, p. 11-14, 1 pl. 

Minch, J. C., Schulte, K. C., and Hofman, George, 1970, A 

middle Miocene age for the Rosarito Beach Formation in 

northwestern Baja California, Mexico: Geological Society of 

America Bulletin, v. 81, no. 10, p. 3149-3154, 2 figs. 

A 12 Shorter Contributions to Paleontology and Stratigraphy 

Moore, E. J., 1963 [1964], Miocene marine mollusks from the 

Astoria Formation in Oregon: U.S. Geological Survey Professional Paper 419, 109 p., 33 pls., 9 figs., 3 tbls. 

---1984, Molluscan paleontology and biostratigraphy of the 

lower Miocene upper part of the Lincoln Creek Formation in 

southwestern Washington: Natural History Museum of Los 

Angeles County, Contributions in Science, no. 351, 42 p., 

180 figs. 

Niem, A. R., 1975, Geology of Hug Point State Park, northern 

Oregon coast: Oregon Department of Geology and Mineral 

Industries, The Ore Bin, v. 37, no. 2, p. 17-36, 16 figs. 

Poore, R. Z., Barron, J. A., and Addicott, W. 0., 1981, 

Biochronology of the northern Pacific Miocene, in Ikebe, 

Nobuo, Proceedings of the IGCP-114 International Workshop 

on Pacific Neogene Biostratigraphy: Osaka, Japan, Osaka 

Museum of Natural History, p. 91-98, fig. 2. 

Schenck, H. G., 1936, Nuculid bivalves of the genus Acila: Geological Society of America Special Paper 4, 149 p. 18 pls., 15 

figs., 17 tbls. 

Smith, J. P., 1912, Geologic range of Miocene invertebrate fossils 

of California: California Academy of Sciences Proceedings, 

ser. 4, v. 3, no. 8, p. 161-182. 

Smith, J. T., 1984, Miocene and Pliocene marine mollusks and 

preliminary correlations, Vizcaino Peninsula to Arroyo la 

Purisima, northwestern Baja California Sur, Mexico, in 

Frizzell, V. A., Jr., ed., Geology of the Baja California 

peninsula: Society of Economic Paleontologists and Mineralogists, Pacific Section, v. 39, p. 197-217, 8 pls. 

Steward, R. B., 1930, Gabb's California Cretaceous and Tertiary 

type lamellibranchs: Academy of Natural Sciences of 

Philadelphia Special Publication 3, 314 p., 17 pls., 5 figs. 

Stinemeyer, E. S., Beck, R. S., Ortalda, R. A., Espenscheid, 

E. K., Bainton, J. D., and O'Keefe, M. S., 1959, Guidebook, Chico Martinez Creek area field trip [California]: San 

Joaquin Geological Society, May 9, 1959, 15 p. 

Weaver, C. E., 1915, The possible occurrence of oil and gas fields 

in Washington: American Institute of Mining Engineers Bulletin, v. 103, p. 1419-1427 (discussion by Milnor Roberts, 

J. B. Tyrell, and others, v. 108, p. 2431-2433). 

---1916a, The post-Eocene formations of western Washington: California Academy of Sciences Proceedings, ser. 4, 

v. 6, no. 2, p. 19-40. 

---1916b, The Tertiary formations of western Washington: 

Washington Geological Survey Bulletin 13, 327 p. 

---1942, Paleontology of the marine Tertiary formations of 

Oregon and Washington: Seattle, University of Washington, 

Publications in Geology, v. 5, 789 p. 

Weaver, C. E., chairman, and others, 1944, Correlation of the 

marine Cenozoic formations of western North America: Geological Society of America Bulletin, v. 55, no. 5, p. 569-

598. 

Wolfe, E. W., and McKee, E. H., 1972, Sedimentary and igneous 

rocks of the Grays River quadrangle, Washington: U.S. Geological Survey Bulletin 1335, 70 p. 

Woodruff, Fay, Savin, S.M., and Douglas, R. G., 1981, Miocene 

stable isotope record: A detailed deep Pacific Ocean study and 

its paleoclimatic interpretations: Science, v. 212, p. 665-668. 
ABBREVIATIONS 

CAS California Academy of Sciences, San Francisco, Calif. 

LACMP Natural History Museum of Los Angeles County, Invertebrate Paleontology Section, Calif. 

LAM Natural History Museum of Los Angeles County, 

Calif. 

USGS United States Geological Survey, Washington, D.C., 

Cenozoic Locality Register. 

USGS M United States Geological Survey, Menlo Park, Calif., 

Cenozoic Locality Register. 

USNM National Museum of Natural History, Washington, 

D.C. 

FOSSIL LOCALITIES 

California Academy of Sciences, San Francisco, Calif. 

CAS 12115. Tillamook Bay, Ore. Astoria Formation. 

CAS 12129. 3.2 m south ofYaquina Bay, Ore. Nye Mudstone. 

CAS 12132. 3 km north of Yaquina Head, Ore. Astoria 

Formation. 

Natural History Museum of Los Angeles County, Calif. 

LAM 5842. On the Columbia River, Wash., between 

Knappton and Grays Point, in the center of 

the NIJzNlf2 sec. 9, T. 9 N., R. 9 W., 

Knappton 7 .5-minute quadrangle. From 

landslide block in upper part of the Lincoln 

Creek Formation. 

U.S. Geological Survey, Washington, D.C. 

USGS 2464. Clallam Bay, Wash. Clallam Formation. 

USGS 6613. South bank of Kern River, Barker's Ranch, 

Kern County, Calif. Temblor Formation. 

USGS 15328. On north side of Yaquina River, southwest 

of Toledo, Ore., 455 m north and 30 m east 

of southwest comer sec. 26, T. 11 S., R. 11 

W., Toledo 15-minute quadrangle, Ore. 

Yaquina Formation. 

USGS 16047. South tip of rock point at junction of ocean 

beach and north shore of Y aquina Bay, Ore. , 

365 m west and 60 m south of intersection of 

Y aquina Bay Bridge and north shore of the 

bay, Oregon. Astoria Formation. 

USGS 18284. Dredgings in unnamed Miocene sediments at 

Coos Bay, Oreg. 

USGS 18860. Road cut on U.S. Highway 101, east side of 

highway, about 305 m south of Spencer 

Creek, Ore. Astoria Formation. 

USGS 18884. From 8-ft massive siltstone, about 10 m 

above base of exposed section in beach cliffs 

forming first headland south of fill at 

Spencer Creek, Ore. Astoria Formation. 

USGS 18890. Road cut on U.S. Highway 101, immediately north of Spencer Creek Bridge. From 

fault block and landslide in unknown stratigraphic horizon. 

USGS 18907. From shale and siltstone exposed in beach at 

low tide, just south of Yaquina Head, Ore. 

Astoria Formation. 

USGS 18939. Slump south of Wade Creek, Ore. Astoria 

Formation. 

USGS 18942a. Float south of Moore Creek, Ore. Astoria 

Formation. 

U.S. Geological Survey, Menlo Park, Calif. 

USGS M1591. On the southwest flank of Pyramid Hill, 

Kern County, Calif., on north side of 

westerly-trending gully, 655 m north, 150m 

east from SW cor. in NWl/4 sec. 14, T. 28 

S., R. 29 E., Rio Bravo Ranch 7.5-minute 

quadrangle. Marine conglomeratic sandstone in the basal part of the Jewett Sand. 

USGS M4132. North bank of small draw in SEl/4NEl/4 

sec. 18, T. 31 S., R. 15 W. Curry County, 

Ore. Concretions in massive sandstone, Empire Formation. 

USGS M4690. Seacliff exposure about 825 m south, 290m 

west ofNE cor., sec. 2, T. 32 S., R. 16 W., 

Curry County, Ore. 

USGS M6385. Cut on east side of road spur #85. NEI/4 

NEI/4SWl/4 sec. 23, T. 6 N., R. 9 W., Cannon Beach 15-minute quadrangle, Clatsop 

County, Ore. Massive, finely laminated 

sandstone of the Angora Peak Member of the 

Astoria Formation. 

USGS M8195. Sea cliff just south of Moore Creek, south of 

Newport, Yaquina 15-minute quadrangle, 

lat 44°34'00" N., long 124°04'30" W., Ore. 

Nye Mudstone. 

USGS M8203. Lat 44°34.4'N., long 124°4.2'W., Yaquina 

15-minute quadrangle, Oregon. Nye Mudstone. 

USGS M8205. Lat44°34.6'N., long 124°04.1'W., Yaquina 

15-minute quadrangle, Lincoln County, 

Ore. Nye Mudstone. 

USGS M8210. Lat44°48.7'N., long 124°01.2'W., Yaquina 

15-minute quadrangle, Lincoln County, 

Ore. Astoria Formation. 

USGS M8213. Lat44°33.5'N., long 124°04.4'W., Yaquina 

15-minute quadrangle, Lincoln County, 

Ore. Nye Mudstone. 

USGS M8220. Lat44°37.4'N., long 124°03.7'W., Yaquina 

15-minute quadrangle, Lincoln County, 

Ore. Nye Mudstone. 

Miocene Pillarian and Newportian Stages of Washington and Oregon A 13 

PLATES 1-4 

Contact photographs of the plates in this report are available at cost from U.S. 

Geological Survey Library, Federal Center, Denver, Colorado 80225 
PLATE 1 

[All specimens are natural size except as noted.] 

FIGURES 1, 4, 7. Patinopecten propatulus (Conrad) 

1. Right valve showing low flat ribs and auricles. Locality USGS 18884. USNM 563236 (x2). 

4. Left valve showing evenly spaced rounded ribs. Locality USGS 18884. USNM 563238. 

7. View of anterior side showing low-rib profile. Same specimen as illustrated in fig. 4. 

2, 3. Molopophorus anglonanus (Anderson) 

Specimen showing noded overlapping sutural color and body whorl spire outline. Locality 

USGS 6613. USNM 563136. 

5, 9, 10. Vertipecten fucanus (Dall) 

5. Latex impression of left valve holotype showing raised median rib. Locality, Astoria, Ore. 

USNM 107790. 

9. Incomplete specimen showing right valve auricles. Locality USGS M8195. USNM 

388232. 

10. Right valve showing irregularly spaced flat ribs and anterior auricle. Locality CAS 12132. 

6, 8. Molopophorus matthewi Etherington 

6. Latex cast. Locality USGS M4690. USNM 245711. 

8. Locality USGS M4132. USNM 245710. 
C.S. GEOLOGICAL SURVE Y BULLETIN 1664-A PLATE 1 

PATINOPECTEN, MOLOPOPHORUS, AND VERT/PECTEN 
PLATE 2 

[All specimens are natural size.] 

FIGURES 1, 4, 5. Patinopecten oregonensis cancellosus Moore. 

1. Right valve ofholotype showing high, regularly spaced ribs. Locality USGS 18284. USNM 

563242. 

4. Latex impression of right valve showing ribs and auricles. Locality USGS M6385. USNM 

328233. 

5. Left valve showing high rounded ribs. Locality USGS 18284. USNM 563239. 

2, 3, 8. Bruclarkia oregonensis (Conrad). Locality USGS 18284. 

2. Specimen showing body-whorl spirals with a few small nodes. USNM 563138. 

3. Specimen showing body-whorl spirals with some large nodes. USNM 563139. 

8. Specimen showing body-whorl spirals without nodes. USNM 563141. 

6, 7. Bruclarkia yaquinana (Anderson and Martin) 

Specimen showing body whorl with small spines. Locality USGS 18284. USNM 563140. 

9. Vertipecten fucanus (Dall) 

Right valve showing irregular spacing of ribs and riblets in interspaces. Locality, Tillamook 

Bay, Ore., Astoria Formation. CAS 12115. 
U.S. GEOLOGICAL SCRVEY BULLETI N 1664-A PLATE 2 

PATINOPECTEN. BRUCLARKIA. AND VERT/PECTEN 
FIGURE 

PLATE 3 

[All specimens are natural size except as noted.] 

1. Patinopecten oregonensis cancellosus Moore 

Latex impression of left valve showing large auricles and smooth rounded ribs. Locality USGS 

M8210. USNM 388234. 

2, 10, 14. Katherinella (Katherinella) angustifrons (Conrad) 

2. Right valve showing shell outline and drill hole. Locality USGS M8205. USNM 388235 . 

10. Left valve showing shell outline. Locality USGS 18890. USNM 563270. 

14. Dorsal view of double-valved specimen shown in fig . 10. 

3, 11 . Epitonium (Cirsostrema) clallamensis Durham 

3. Specimen showing thick axial ribs crossed by spiral sculpture. Locality USGS Ml8942a. 

USNM 388236. 

11. Specimen showing axial ribs and spiral sculpture. Locality USGS M1591 . USNM 

388237. 

4, 5. Anomalocardia carmanahensis (Clark) 

4. Latex impression of right valve showing thick radial sculpture with fine radial sculpture 

where eroded. Locality USGS 15328. USNM 388238. 

5. Left valve with thick concentric sculpture. Locality USGS 2464. USNM 388239. 

6. Patinopecten propatulus (Conrad) 

Incomplete right valve showing auricles. Locality USGS 18860. USNM 63237. 

7. Macoma albaria (Conrad) 

Right valve showing outline. Locality USGS 18284. USNM 563297 (X2). 

8. Lucinoma acutilineata (Conrad) 

Lectotype showing outline and concentric sculpture. Locality Astoria, Ore. USNM 3519. 

9. Securella ensifera (Dall) 

Left valve showing fine concentric sculpture. Locality USGS M8220. USNM 388240. 

12. Musashia (Nipponomelon) shikami Moore 

Specimen showing narrow axial ribs and shallow suture. Locality LAM 5842. LACMP 

6648 .13 . 

13 . Dosinia (Dosinia) whitneyi (Gabb) 

Outline of right valve. Locality USGS 18284. USNM 563261 . 

15. Musashia (Miopleiona) indurata (Conrad) 

Specimen showing thick axial ribs deflected by deeply impressed suture . Locality USGS 

18284. USNM 563174. 

16. Cyclocardia subtenta (Conrad) 

Outline of left valve. Locality USGS 16047. USNM 563260. 
U.S. GE OLOGICAL SU RVEY BULLETIN 1664 -A PLATE 3 

10 

16 

PATINOPECTEN, KATHERINELLA, EPITONIUM, ANOMALOCARDIA, _MACOMA, LUCINOMA, 

SECURELLA, MUSASHIA , DOSINIA, AND CYCLOCARDIA 
PLATE 4 

[All specimens are natural size except as noted .] 

FIGURES 1, 9, 11. Vertipectenfucanus (Dall) 

1. Right valve showing irregularly spaced ribs. Locality USGS M8203 . USNM 391847. 

9. Left-valve fragment showing raised median rib . Locality USGS M8213. USNM 391848. 

11. Left valve showing raised median rib and irregular ribbing. Locality USGS 18831. USNM 

563250. 

2. Ficus modesta (Conrad) 

Outline of specimen. Locality USGS 18939. USNM 563212. 

3. Musashia (Nipponomelon) shikami Moore 

Specimen showing thin axial ribs. Locality LAM 5842. LACMP 6650. 

4, 6. Saccella amelga Moore 

4. Right valve showing outline and concentric sculpture. Locality USGS 18907. USNM 

563214 (X3). 

6. Dorsal view. Same specimen illustrated in figure 4. 

5. Patinopecten oregonensis cancellosus Moore 

Ventral view. Locality USGS 18284. USNM 563239. 

7, 10. Epitonium (Cirsostrema) clallamensis Durham 

Locality USGS 1591. USNM 388237. Same specimen as pl. 3, fig . II. 

7. Basal disk of specimen. 

10. Specimen showing thick axial costae. 

8. Priscofusus aff. P. geniculus (Conrad) of Moore, 1963 

Specimen showing sculpture. Locality 3.2 km south of Yaquina Bay, Ore. CAS 12129. 
U.S. GEOLOGICAL SURVEY BULLETIN 1664-A PLATE 4 

4 

7 

VERT/PECTEN, FICUS, MUSASHIA, SACCELLA, PATINOPECTEN, EPITONIUM, AND PRISCOFUSUS 

CHAPTER B 

A New Species of lsogramma (Brachiopoda) 

From the Pennsylvanian of North-Central Texas 

By BRUCE R. WARDLAW, DAVID E. SCHINDEL, and 

ELLIS l. YOCHELSON 

U.S. GEOLOGICAL SURVEY BULLETIN 1664 

Shorter Contributions to Paleontology and Stratigraphy 

CONTENTS 

Abstract Bl 

Introduction Bl 

Occurrence and depositional setting of Isogramma coopi Bl 

Isogrammidae B2 

Systematic paleontology B4 

References cited BS 

PLATE 

[Plate follows References Cited] 

1. Isogramma coopi 

FIGURES 

1. Map showing location of Mt. Zion Cemetery Bl 

2. Shell structure of /sogramma coopi B3 

3. Diagrammatic interpretation of interior of /sogramma coopi BS 

Contents Ill 

A New Species of lsogramma (Brachiopoda) 

From the Pennsylvanian of North-Central Texas 

By Bruce R. Wardlaw, David E. SchindeP, and Ellis L. Yochelson 

Abstract 

lsogramma coopi, new species, is described from the Gonzales Limestone Member of the Graham Formation (Pennsylvanian) of north-central Texas. It is interpreted as having lived in 

a coralgal patch attached to corals and other hard substrate 

with its anterior commissure vertical. The lsogrammidae are 

transferred to the order Strophomenida. 

INTRODUCTION 

lsogramma has long been known from its distinctive shell 

fragments and has been reported from several localities and 

stratigraphic levels in the Pennsylvanian of north-central 

Texas. Several new, whole specimens of lsogramma coopi 

n. sp. were collected in apparent life position by the authors 

during summer 197 6 and 1977 from the Gonzales Limestone Member of the Graham Formation, Cisco Group (Upper Pennsylvanian, Virgillian). These collections represent 

the only ones with abundant, whole, articulated specimens. 

None has been reported or illustrated. The collections provide an opportunity to reassess the genus lsogramma and its 

taxonomic position. 

I. coopi is found in the Gonzales Limestone Member 

exposed in the bluffs and gullies approximately 200 meters 

east-northeast of the Mt. Zion Cemetery on the La Casa 

quadrangle, Stephens County, Tex. (fig. 1). This limestone 

caps an 8.5-m bluff of richly fossiliferous, medium-lightgray marine mudstone in the Finis Shale Member of the 

Graham Formation. Additional exposures occur in gullies 

approximately 150 m east of the cemetery, roughly 8 m 

stratigraphically below the sandstone on which the cemetery 

is built. 

OCCURRENCE AND DEPOSITIONAL SETTING 

OF /SOGRAMMA COOP/ 

The Gonzales Limestone Member is laterally persistent 

for less than 20 kilometers in central Stephens County. It 

1

Yale University, New Haven, Conn. 06520 

continues along strike virtually unchanged in composition or 

thickness for 11 km to the north-northeast and for 8 km to 

the south of the Mt. Zion Cemetery before pinching out. 

Beyond this limited lateral extent, the underlying Finis 

Shale Member and the overlying Gonzales Shale Member, 

both of Sellards, Adkins, and Plummer (1933), form an 

undivided shale sequence. The Gonzales Limestone is identified and mapped in other areas of north-central Texas 

primarily on the basis of its relative position in the stratigraphic sequence. The composition and thickness of limestone are markedly different in those other areas. Thus, the 

correlation between the several limestone bodies called 

Gonzales is not precise; these lentils may or may not be time 

equivalents. No evidence from field observations indicates 

that the Gonzales Limestone Member was at one time laterally persistent throughout north-central Texas and was subsequently limited in extent by erosion. It is more easily 

demonstrated that conditions under which this unit was de98°45 

STEPHENS COUNTY 

99'00' 

10 15 

Figure 1. Location of Mt. Zion Cemetery in Stephens County, 

Texas. 

New Species of lsogramma, North-Central Texas 81 
posited differed among areas that were separated by regions 

of clastic deposition in which limestone was prevented from 

forming. 

The fauna of the Gonzales Limestone Member of central 

Stephens County is dominated by abundant solitary rugose 

corals. These lophophyllidioid corals are laterally compressed, and some reach lengths exceeding 6 centimeters. 

They shed conspicuously as yellow-tan debris onto the 

slopes of the Finis Shale Member below. Individual corals 

are found in situ, generally with apex lowermost, in positions ranging from upright to recumbent. Most specimens 

grow with straight axes, or with only slight curvature, suggesting that excavation and toppling of individuals by excessive water movement was not common. Algae and ectoprocts occurring as epibionts on the outer surfaces of the 

corals indicate shallow, gently agitated, normal marine conditions. Occurrence of a range of coral growth stages in life 

position strongly suggests lack of faunal mixing or winnowing, although the presence of clay in the Gonzales Limestone indicates sufficient current action for the influx of very 

fine clastic particles. These clay-sized particles probably 

settled quickly to the bottom as a result of the wave-damping 

effect on the coral cover. 

Other constituents of the fauna in the Gonzales Limestone 

Member at the Mt. Zion Cemetery include colonial Syringopora corals, crinoid stems, the high-spired gastropod 

Taosia, robust spiriferoid brachiopods, Isogramma coopi, 

rare specimens of Enteletes, and infaunal pelecypods belonging to the genera As tart ella, Schizodus, and Allorisma. 

All bivalved taxa are represented by at least a few articulated, unabraded specimens. Crinoid columnals remain articulated in lengths up to 10 em; many of these stems are 

encrusted and bleached lengthwise along one side, indicating an interval of post-mortem, preburial response on the 

bottom. These observations support the suggestion that this 

20-km-long lentil of the Gonzales Limestone Member was 

deposited in a shallow, gently agitated, normal marine setting. This local limestone probably represents the growth of 

a meadowlike patch, densely carpeted by a coral-dominated 

assemblage, analogous to modem Thallassia-dominated 

subtidal meadows of the Caribbean. 

Transition from the preexisting mud-bottom condition of 

Finis Shale Member deposition to the shelly-bottom condition under which the overlying Gonzales Limestone Member accumulated seems geologically rapid; the diverse 

mollusk -dominated fauna of the Finis Shale Member is replaced vertically by the coral-dominated assemblage within 

a few centimeters of strata. Rugose corals were not found in 

the underlying Finis, although extensive collecting from the 

weathered slopes of this unit has yielded a few lophophyllidioid corals, all of which are laterally crushed and stained 

yellow tan. We believe that these individuals originated in 

the Gonzales, as no rugosans have been found in situ below 

this unit. A vertical sequence of bulk sediment samples 

taken through the entire Finis Shale at the Mt. Zion Ceme82 Shorter Contributions to Paleontology and Stratigraphy 

tery was disaggregated and wet -sieved for fossils above the 

200 mesh fraction (0.074 millimeter and larger). These 24 

samples represented more than 60 kilograms of sediment 

and produced thousands of specimens greater than 1. 0 mm; 

however, not a single coral adult, protocorallium, or fragment was among them (Schindel, 1979). 

The presence of clay in the Gonzales Limestone Member 

shows that influx of terrigenous clastics did not cease before 

the growth of the coral thicket, though turbidity may have 

decreased to a level tolerable to the corals. Although we 

cannot demonstrate that environmental conditions changed 

at or near the level of faunal replacement, it is apparent that 

rugose corals were not pr~sent in the area before Gonzales 

deposition. We suggest that the initial arrival of coral 

colonists was the first step in the change from a quiet-water, 

mud-bottom environment, dominated by low-level depositand suspension-feeding mollusks, to a very quiet-water, 

wave-damped shelly bottom environment, dominated by 

epifaunal grazers and by filter-feeders, including/. coopi. 

ISOGRAMMIDAE 

Currently (Rowell, 1965, p. 359), the Isogrammidae are 

associated with the Eichwaldiidae in the superfamily Eichwaldiacea. Megapleuronia Cooper (1952) and its junior 

synonym, Schizopleuronia Liao (1983), are the only other 

genera included in the Isogrammidae. Megapleuronia is 

differentiated from /sogramma by its costate or plicated 

anterior margins. All other features are similar to I sogramma . The common features of the Isogrammidae and · 

Eichwaldiidae are shell punctation and a pedicle plate (urnbona! plate of Rowell, 1965). The Eichwaldiidae have an 

opening at the anterior end of the pedicle place communicating to the outside of the valve. This also results in an interior 

raised posterior plate in the pedicle valve anterior to the 

opening to the pedicle plate. This opening to the pedicle 

plate has been postulated for the Isogrammidae (Dittmar, 

1872; Schmidt, 1931), but we find no evidence for it in our 

specimens or in those illustrated by Cooper (1952) or 

Cooper and Grant ( 197 4). 

The Isogrammidae differ from the Eichwaldiidae in having no teeth, a lophophore platform, and articulation 

achieved by a prominent trilobate cardinal process extending posterior to the hingeline as in the Productidina. Isogramma has a lophophore platform (brachial ridges? of 

Cooper and Grant, 197 4) that is diagnostic of Strophomenida. The valve shape and fit of the Isogrammidae are 

like that of the Strophomenida, whereas the Eichwaldiidae 

valve shape and fit are more like the Rhynchonellida. The 

Isogrammidae occur in Carboniferous and Permian rocks, 

and the Eichwaldiidae are found in Ordovician and Silurian 

rocks, a significant hiatus between occurrences. 

The punctation and shell structure found in the Isogrammidae differ from that of most brachiopods. The punctae are 

large and occupy as much space as the intervening shell. 
The ridges of shell coalesce to form the exterior ornamentation of concentric ridges; these ridges can cover the entire 

valve, as reported by Cooper and Grant (1974) or can leave 

interridge areas exposing punctae to the exterior (fig. 2; 

Schmidt, 1931). Interior impunctate shell material forms the 

cardinal process, shaft, and long median septum. Similar 

impunctate shell is deposited to form the pedicle plate, with 

no punctate layer deposited over it. The pedicle plate narrows and ends at or near the posterior end of the beak and 

does not have an anterior opening to communicate with the 

exterior. The delthyrium of the pedicle valve is filled with 

the cardinal process of the brachial valve. It is hard to 

imagine how any pedicle could have been extended from 

this shell. The pedicle plate is not covered by the external 

shell layers of the punctate shell and concentric ridges but 

appears internal to these layers. Because the pedicle plate is 

composed of impunctate shell material like some internal 

features that were covered by living mantle tissue and because it is internal to the normal punctate shell forming the 

exterior, perhaps it, too, was covered by living tissue. The 

pedicle plate, therefore, was probably not a "pedicle track" 

but may have been a specialized attachment surface. Communication to the interior may be maintained through the 

bordering punctae along the margin of the pedicle plate. 

These punctae appear to be the only "openings" available to 

the pedicle plate. Nevertheless, /sogramma has a different 

Figure 2. Shell structure of lsogramma coopi, all views X100. A, View of median cross section showing interior and 

interior valve surfaces of an articulated specimen; white represents the calcite skeleton, and clay with some silt fill 

open punctae and, in part, line some of the interior, but clay is post-mortem and depositional in occurrence; generally the punctae open to the interior. 8, View of median cross section showing both exterior and interior surfaces 

of a brachial valve, only about one-half the punctae are covered by ridge-forming exterior ornament, the other onehalf are open to the exterior. C, View of median cross section showing exterior and interior surfaces of a brachial 

valve with poorly developed ridges. D, View of oblique median cross section showing exterior surface of pedicle 

valve w ith poorly developed ridges, slightly more than one-half the punctae are covered . 

New Species of /sogramma, North-Central Texas 83 
attachment than members of the Eichwaldiidae which do 

have an obvious "pedicle track" and an obvious pedicle 

opening to the exterior at the anterior of the "track" and 

probably had a pedicle. 

The Isogrammidae developed during the explosive radiation of the Strophomenida; they are articulated like the Productidina of the Strophomenida. Though the shell structure 

is aberrant for a member of the Strophomenida, the Strophomenida being pseudopunctate, or rare! y impunctate, all 

other features support a relationship with that order. This 

argument is not new; Schmidt (1931) also discussed this 

possible affinity. Modification of hollow taleolae, as in the 

Chonetidina, could lead to the shells of the Isogrammidae. 

The Stropheminida include the Oldhaminidina and many 

strange Productidina. In our view, the Isogrammidae can fit 

comfortably in the order without unduly extending its limits. 

SYTEMATIC PALEONTOLOGY 

Genus I sogramma Schuchert, 1929 

Isogramma coopi Wardlaw, Schindel, 

and Yochelson, new species 

Plate 1 , figures 1- 17 

The specific name is in honor of "Coop," G. Arthur 

Cooper, emeritus curator, Department of Paleobiology, 

Smithsonian Institution. 

Holotype. - USNM 305974, pl. 1, figs. 11-12. 

Diagnosis.-This species is recognized by the folding of 

the valves and its oval shape. 

Description. - Medium to large brachiopod, with a 

roughly oval shape, widest just anterior to hinge, valves 

concavoconvex. Pedicle valve flatly convex with broad median fold and shallow lateral sulci anteriorly; interarea short 

but wide, tapering laterally, with smaller triangular interarea 

short but wide, tapering laterally, with small triangular 

delthyrium, beak slightly recurved over interarea. Brachial 

valve shallowly concave with median sulcus and lateral 

folds anteriorly; no interarea. 

Shell composed of two layers: a highly punctate, honeycombed layer making up most of the valve and an impunctate layer restricted to the center part of each valve. The 

punctae are round, as large as the intervening shell material. 

External ornament of concentric ridges produced by intervening shell coalescing, sealing some punctae from exterior. Interior of brachial valve with cardinal process, shaft, 

and median septum all composed of impunctate inner shell; 

exterior covered by punctate shell; pedicle valve interior 

with pedicle plate made up of impunctate "inner shell," 

exteriorly not covered. 

Shell ornamented by folds and elevated concentric ridges; 

one broad median fold with low lateral sulci on pedicle 

valve and complementary median sulcus with two lateral 

folds on brachial valve; concentric ridges randomly ending, 

beginning, and bifurcating, locally some crosscutting, but 

84 Shorter Contributions to Paleontology and Stratigraphy 

giving the overall impression of concentric ornament; ridges 

start at and perpendicular to hinge, ridges forming wavy 

ornamentation at various points on valve; punctae exposed 

in interridge areas, interridge areas approximately one-half 

the width of ridges; concentric ornament interrupted by narrow triangular pedicle plate, starting near posterior of beak 

and extending anteriorly for a variable distance commonly 

about one-third to one-half the length of valve; pedicle plate 

is notched in middle. 

Pedicle valve interior rarely observed, with deep, troughlike posterior depression in middle of valve made up of 

impunctate shell representing interior of the pedicle plate, 

remainder of valve with radially arranged small ridges and 

depressions, anteriomedianly, representing muscle attachment or pallial marks. Brachial valve interior with thick, 

short, trilobate cardinal process supported by a thick shaft 

becoming a high median septum extending anteriorly nearly 

entire length of valve, all composed of impunctate shell; 

articulation accomplished by inner "socket" ridge that forms 

shallow groove to hinge, groove receives thickened margin 

of pedicle valve interarea; cardinal process completely fills 

delthyrium; muscle scars consisting of radially arranged 

ridges and depressions forming large triangular areas 

anteriormedianly, posterior one-third of muscle scars 

depressed, anteriorly muscle scars elevated; lophophore 

platform simple, outlined by low "socket" ridge posteriorly 

and low ridge laterally and anteriorly, forming symmetric 

wings, narrowing medianly about the posterior shaft and 

median septum (fig. 3). Brachial valve interior surface 

marked by numerous pits (punctae). 

Discussion. -The pedicle plate has no direct connection 

to the interior of the brachiopod and, thus, probably does not 

represent a "pedicle track" (Cooper and Grant, 1974). It is 

composed of impunctate shell material, which in the 

brachial valve, represents inner shell. This implies that impunctate shell is secreted by mantle inside the mantle-shell 

margin where normal (punctate) shell deposition takes 

place. Because, in Isogramma, the impunctate shell appears 

to represent "inner" shell material that was probably 

secreted by covering mantle tissue, the inner shell exposed 

in the pedicle plate may have been covered by mantle. The 

pedicle plate seems to have been involved in attachment, 

and commonly corals are cemented to it. This cementation 

appears postdepositional, but the proximity of the fossils 

seems original. No evidence exists that /sogramma could 

cement itself to a substrate. However, the proximity of 

possible attachment objects implies attachment, and this 

may have been accomplished by a living attachment surface 

of exposed mantle. The occurrence of/. coopi in upright life 

position within a coral thicket also suggests some attachment. Communication to the interior for the live exposed 

mantle is difficult to demonstrate, but access could be 

through the open punctae bordering the pedicle plate. 

Mantle tissue probably existed in all the punctae, at least 

sometime during the brachiopod's life. The mantle in the 
punctae bordering the pedicle plate was probably specialized and extended to cover the plate, which prevented outer 

shell development and made an attachment surface during 

life. 

Isogramma coopi differs from /. renfrarum Cooper 

(1952), which occurs in the Finis Shale Member in northcentral Texas, in its smaller size, oval shape, and folding on 

brachial valve. This difference may be due to different living environments-/. renfrarum occurred on marine mudflats, and/. coopi, in a coralgal thicket. The folding in/. 

coopi may have been a response for sharper separation of 

incoming and outgoing currents in a crowded environment. 

In its anterior folding, Isogramma coopi most closely 

resembles/. lobatum Cooper and Grant from the Leonardian 

(late Early Permian) of west Texas, though the folding is 

less pronounced in /. coopi. I. coopi differs internally in 

having a different-shaped lophophore platform and in having radial ornament confined to the muscle scars./. lobatum 

is based on only two brachial valves, so further comparison 

is precluded. 

Occurrence. -Gonzales Limestone Member of the Graham Formation (Upper Pennsylvania, Virgilian), Mt. Zion 

Cemetery, Stephens County, Texas. 

Figure 3. Diagrammatic interpretation of the interior of lsogramma coopi. A, Brachial valve showing cardinal process 

and median septum, lophophore platform, and muscle scars; 

impunctate shell makes up only the cardinal process and septum. 8, Pedicle valve showing interior surface of pedicle plate 

of impunctate shell and muscle scars; the interior of the pedicle 

plate forms a trough. 

REFERENCES CITED 

Cooper, G. A., 1952, Unusual specimens ofthe brachiopod family 

Isogrammidae: Journal of Paleontology, v. 26, p. 113-119. 

Cooper, G. A., and Grant, R. E., 1974, Permian brachiopods of 

West Texas: Smithsonian Contributions to Paleobiology, 

v. 2, no. 15, p. 233-793. 

Dittmar, A. von, 1872, Ueber ein neues Brachiopoden Geschlecht 

aus dem Bergkfalk: St. Petersburg, Russische-Kaiserliche 

mineralogische Gesellschaft, Verhandlungen, ser. 2, no. 7, 

14 p. 

Liao Zhuo-ting, 1983, Two new genera of brachiopods from the 

Heshan Formation (Upper Permian) of Guangxi: Acta 

Palaeontologica Sinica, v. 22, no. 6, p. 637-641. 

Rowell, A. 1., 1965, Family Isogrammidae, in Moore, R. C., ed., 

Brachiopoda, Part H of Treatise on Invertebrate Paleontology: 

Geological Society of America and University of Kansas 

Press, v. 1, p. 361. 

Schindel, D. E., 1979, Paleoecology and systematics of the Pennsylvanian gastropoda of north-central Texas: Harvard University, unpublished Ph. D. dissertation, 465 p. 

Schmidt, Hermann, 1931, Bau und Anjeftungsweise des Brachiopoden /sagramma aus dem Oberkarbon Karntes: PaHiontologisch Zeitschrift, v. 13, no. 4, p. 278-283. 

Sellards, E. H., Adkins, W. S., and Plummer, F. B., 1933, 

Stratigraphy, V. 1; The Geology of Texas: Austin, Texas 

University Bulletin 3232, 1000 p. 

New Species of lsogramma, North-Central Texas 85 

PLATE 1 

Contact photograph of the plate in this report is available at cost from U.S. 

Geological Survey Library, Federal Center, Denver, Colorado 80225 
PLATE 1 

lsogramma coopi 

[All figures of holotypes and paratypes, xl, unless stated otherwise. 

Specimens articulated, and partially covered by caliche and clay.] 

FIGURES 1-2. Ventral and dorsal views USNM 305972. 

3. Dorsal view, showing part of pedicle interior USNM 399544. 

4-5. Dorsal and anterior views, showing folding USNM 305971. 

6-7. Dorsal and ventral views, showing long pedicle plate USNM 305970. 

8. Interior view of brachial valve USNM 399545. 

9-10. Dorsal and interior view of brachial valve USNM 399546. 

11-12. Ventral and dorsal view of holotype USNM 305974. 

13. Interior view of brachial valve USNM 399548. 

14-15. Dorsal and ventral interior of brachial valve views USNM 305969. 

16-17. Ventral view of specimen with coral attached to pedicle plate with dorsal view of another attached 

specimen; X3 enlargement to show surface ornament and punctae of lower left side of same specimen 

USNM 305973. 
U.S. GEOLOGICAL SURVEY BULLETIN 1664-B PLATE 

ISOGRAMMA 

CHAPTER C 

Middle and Upper Triassic Marine Ostracoda 

From the Shublik Formation, Northeastern 

Alaska 

By I. G. SOHN 

U.S. GEOLOGICAL SURVEY BULLETIN 1664 

Shorter Contributions to Paleontology and Stratigraphy 

CONTENTS 

Abstract CI 

Introduction CI 

Purpose and scope C I 

Previous work CI 

Acknowledgments C2 

Preservation and laboratory techniques C2 

Geologic setting C3 

Age of the ostracodes C3 

Paleogeographic implications C4 

Environment of the ostracodes CS 

The Hungarella-Ogmoconcha problem CS 

USGS Mesozoic fossil collection localities C6 

Systematic paleontology C7 

Family Bairdiidae Sars, 1888 C7 

Subfamily Bairdiinae Sars, 1923 C7 

Genus Hiatobairdia Kristan-Tollmann, 1970 C7 

H.? sp. ex gr. H. arcuata C7 

Genus Cornutobairdia Kristan-Tollmann, 1970 C7 

C. reidae n. sp. CS 

?Family Paracyprididae Sars, 1923 C9 

Genus Triassocypris Kozur, 1970 C9 

T.? sp. C9 

Gen. and sp. indet. C9 

Family Covracytheridae n. fam. CIO 

Genus Covracythere Gramm, 1975 CIO 

C. gryci n. sp. CIO 

C. binoda n. sp. Cli 

Genus Dettermania n. gen. CII 

D. truncata n. sp. CII 

Family unknown CI2 

Genus Rhombocythere Anderson, 1964 CI2 

R. sp. CI2 

Family Healdiidae Harlton, 1933 CI3 

Genus Healdia Roundy, 1926 CI3 

"Healdia" sp. 1 CI4 

"H. " sp. 2 CI4 

"H." sp. 3 CI4 

Genus Pseudobythocypris Shaver, 1958 CI4 

P .? sp. CI4 

Genus Ogmoconcha Triebel, 1941 CIS 

0. sp. aff. 0. owthropensis CIS 

0. alaskaense n. sp. CI6 

0. unicerata n. sp. CI6 

0. tailleuri n. sp. C17 

0. marquardti n. sp. CIS 

0. sp. CIS 

0. sp. aff. Hungarella limbata CIS 

Family Cavellinidae Egorov, 1950 CI9 

Subfamily Ussuricavininae Gramm, 1969 CI9 

Genus Cavussurella Gramm, 1969 CI9 

C. grammi n. sp. C20 

C.? spp. C20 

Subfamily Recytellinae Gramm, 1970 C2I 

Genus Recytella Gramm, 1970 C2I 

R. sp. 1 C21 

R. sp. 2 C2I 

References C2I Contents Ill 
PLATES 

[Plates follow References I 

1. "Healdia" 

2. Recytella, Pseudobythocypris?, Hiatobairdia?, Covracythere 

3. Cornutobairdia, Cavussurella, Ogmoconcha 

4. Cavussurella 

5. Ogmoconcha 

6. Ogmoconcha 

7. Covracythere, Dettermania 

8. Ogmoconcha 

9. Ogmoconcha 

10. Ogmoconcha, Cavussurella, Rhombocythere 

11. Triassocypris?, Ogmoconcha, Cavussurella, Rhombocythere 

FIGURE 

1. Map of northern Alaska showing location of reference section of Shublik Formation C2 

TABLES 

1. Stratigraphic occurrences of taxa in Alaska C4 

2. Paleozoogeographical provinces and ages of related taxa C4 

IV Shorter Contributions to Paleontology and Stratigraphy 
Middle and Upper Triassic Marine Ostracoda 

From the Shublik Formation, Northeastern 

Alaska 

By I. G. Sohn 

Abstract 

Twenty-two taxa from beds dated by megafossils as Ladinian 

through Norian are described and illustrated in 7 new species, 

13 in open nomenclature, and 1 as Gen. and sp. indet. The 

Hungarella-Ogmoconcha problem is discussed, and specimens of Ogmoconcha from the Carnian of Hungary are illustrated as evidence that the genus was present during the Triassic. Twelve of the taxa are restricted to the Ladinian part of the 

Shublik Formation of the reference section, one taxon is restricted to the Carnian, and six taxa are restricted to the Norian. 

Related genera have been recorded from the Middle Triassic of 

the Primor'ye Zoogeographical Province of the Pacific Realm 

and from the Middle and Upper Triassic in the Tethyan Zoogeographical Province of Eurasia. 

The following taxa are included: Cavussurella grammi n. sp., 

C.? sp. 1, C.? sp. 2, Covracytheridae n. fam., Covracythere 

binoda n. sp., C. gryci n. sp., Dettermania truncata n. gen., n. 

sp., Ogmoconcha tailleuri n. sp., 0. unicerata n. sp., 0. 

a/askaense. n. sp., 0. marquardti n. sp., 0 .? sp. aff. Hungarella 

limbata (Reuss, 1868), 0. aff. 0. owthropensis (Anderson, 

1964), Cavussure/la? sp. 1, C?. sp. 2, "Healdia" sp. 1, "H" 

sp. 2, "H" sp. 3, Hyatobairdia? ex gr. H. arcuata KristanTollman, 1970, Recytella sp. 1, R. sp. 2, Triassocypris? sp., 

Pseudobythocypris? sp. Rhombocythere? sp., and Gen. and sp. 

indet. 

In addition, Cornutobairdia reidae n. sp. from the Lewes 

River Formation (Norian), Yukon Territory, Canada, is described. This species is representative of an abundant and 

varied silicified ostracode assemblage that differs on the 

generic level from those in northern Alaska. This assemblage is 

similar to ostracodes from Nevada and to taxa described from 

the Carnian and Rhaetian of the Tethyan Zoogeographical Region. During the Middle Triassic (Anisian and Ladinian), the 

sea that became northern Alaska was located in the Primor'ye 

Zoogeographical Province not directly connected with the 

Tethyan Zoogeographical Region. During the Late Triassic 

(Norian and ?Rhaetian), that sea had connections with the 

Tethyan Zoogeographical Province of Eurasia. Northern Alaska 

is not one of the accretionary exotic terranes postulated for 

western North America and southern Alaska. 

INTRODUCTION 

Purpose and Scope 

The discovery and production of oil in the North Slope of 

Alaska involved detailed geologic, stratigraphic, and paleontologic studies by the U.S. Geological Survey (USGS) 

and many private companies. This report deals with Middle 

and Late Triassic ostracodes from the reference section of 

the Shublik Formation, 10.4 kilometers N83°W of the confluence of Fire Creek and the Sadlerochit River (fig. 1) in 

the Mount Michelson quadrangle (Detterman and others, 

1975, p. 14-16, fig. 6). Stage assignments for the units in 

this reference section are based on megafossils identified by 

N. J. Silberling (Detterman and others, 1975, p. 43). Because ostracodes also are present in boreholes in the North 

Slope (Sohn, 1984a, p. 334), description of the ostracodes 

from surface collections makes these microfossils available 

for surface and subsurface identification. 

Previous Work 

From 1857 through 1966, only 25 publications dealing 

with marine Triassic ostracodes were published (Sohn, 

1968, p. 6, 64), and all were from Europe and Asia. During 

the past two decades, the number of publications on the 

Triassic ostracodes from Europe and Asia has increased 

dramatically. Sohn (1965) recorded Hungarella? spp., 

Paracypris? spp., Darwinula? sp., and unidentified 

steinkems in 30 collections of very poorly preserved pyritized ostracodes from the Shublik Formation on Dodo Creek 

about 10 km east-northeast of the Fire Creek reference section. In the same publication, the following taxa were 

recorded for silicified ostracodes from the Grantsville Formation (Ladinian), Shoshone Mountains, Nye County, Nev. 

(USGS Mesozoic loc. M76): Acratia? sp., Carinobairdia? 

sp., Cytherelloidea n. sp. 1, Cytherelloidea n. sp. 2, new 

genus Thlipsuracea?, Gen. indet. Beyrichicopina?, Gen. 

indet. Cytheracea, and Gen. indet. Healdiidae. 

Middle And Upper Triassic Marine Ostracoda, Northeastern Alaska Cl 
Harlan Bergquist gave me 37 slides with ostracodes he 

found while studying the foraminifers from the Fire Creek 

reference section of the Shublik Formation for R. L. Detterman. In 1973, I reported that they contained Hungarella 

spp., Bairdia sp. (one carapace), and steinkerns of undetermined genera. As result of my report, Detterman sent me 88 

samples from the reference section of the Shublik Formation 

that had been prepared by grinding for mineralogical 

studies. Sixty-one of these contained ostracodes. Both suites 

of samples from the reference section were documented by 

collection numbers and by distances measured in feet above 

the base of the Shublik Formation. These samples were 

small, ranging in dry weight from 22 to 104 grams; the 

ostracodes recovered, which varied from 1 to more than 30 

specimens per sample, provided the ostracodes for this 

study. 

Acknowledgments 

I thank the following colleagues in the Geological Survey 

for specimens, information, and advice: Jean M. Berdan, R. 

L. Detterman, J. T. Dutro, Jr., George Gryc, N.J. Silberling, I. L. Tailleur, and the late Harlan Bergquist. Kathleen 

M. Flynn, October 1981 to May 1982, Jane A. Bubek, June 

1982 to August 1982, and T. Chad Walter, October 1982 to 

April 1984, processed and picked the samples, and Marija 

Balanc assisted with translations from the Russian. Pamela 

Reid, University of Miami, Florida, supplied etched residue 

100 200 300 400 KILOMETERS 

and limestone samples from the Lime Peak Formation (Norian), Yukon, Canada. Dr. M. N. Gramm, Vladivostok, 

U.S.S.R. , compared scanning electron micrographs of two 

taxa with the types and duplicates of taxa he had described 

from the Primor'ye Territory, U.S.S.R. The National 

Petroleum Reserve in Alaska provided technical support 

during fiscal years 1982 and 1983 to process these samples, 

as well as portions of borehole cores that I selected in Menlo 

Park during January 26 and 27, 1982. 

Preservation and Laboratory Techniques 

All the samples were treated in Quaternary-0, sieved and 

picked using a binocular microscope. Selected specimens 

were prepared for scanning electron microscope (SEM) photomicrography. Both methods have been described by Sohn 

(1983. p. 10). 

Because the samples had been crushed previously, most 

of the ostracodes are either steinkerns or broken or corroded 

carapaces and are small, from 0.4 to 0.8 millimeter in greatest length. Clean dissociated valves are rare. The outer 

surfaces of many of the carapaces, particularly those taxa 

with smooth surfaces. are rough because they are coated 

with an as yet undetermined mineral (pl. 6, figs. 15-18). 

Some have adhering mineral grains (pl. 6, figs. 6-9), and 

others are pitted and gouged (pl. 9, figs. 15, 18). On some 

of the steinkerns and broken carapaces, either the hinge 

structure or the adductor muscle-attachment scar is exposed 

Figure 1. Map of northeastern Alaska showing location of Fire Creek reference section of Shublik Formation; 1 is the Fire Creek 

outcrop section. 

C2 Shorter Contributions to Paleontology and Stratigraphy 
(pl. L figs. 7, 8. 15, 16. 18. 20; pl. 5, figs. 14, 16; pl. 8, 

figs. 25. 26; pl. 9. figs. 11, 12, 22, 23; pl. 10. figs. 18, 19, 

26; pl. 11, fig. 26). These two morphologic characters are 

particularly important in the generic and suprageneric classification of ostracodes. 

GEOLOGIC SETTING 

Current interpretations suggest that modern-day Alaska is 

composed of at least two unrelated blocks: A northern segment consisting of the North Slope and the Brooks Range 

that was once connected to the Canadian Arctic Islands 

(Grantz. Johnson, and Sweeny, 1982, pl. Ill) and a central 

and southern portion composed of accretionary terranes that 

are part of the active convergent Pacific microplates (Jones, 

Silberling, and Hillhouse, 1978, p. 71-74; Plafker and 

Jones, 1982. p. 78, fig. I). The Brooks Range and the 

Canada Basin may have formed simultaneously during the 

Late Jurassic or Early Cretaceous by the counterclockwise 

rotation of Arctic Alaska (Mull, 1984; Tozer 1982, p. 

1 085). Several studies, however, suggest no post-Triassic 

rotation (Churkin. 1972; Churkin and Trexler, 1981; Dutro, 

1981). The affinities of the ostracodes, on the generic level, 

to those in the Primor'ye Territory support the latter view. 

With one exception. Cornutobairdia reidae n. sp., from 

the Lewes River Formation (Norian), Yukon Territory, 

Canada, the ostracodes described herein are from the Shublik Formation in the northern segment of Alaska. The distinctive lithology, namely thin-bedded black phosphatic 

limestone and dolomite, shale and chert. and abundant fossils. make the Shublik Formation a readily recognized stratigraphic unit in northern Alaska. This formation represents a 

condensed sequence of rock of remarkably uniform thickness. Detterman and others ( 197 5, p. 14-16) designated the 

Fire Creek outcrop section as the reference section of the 

Shublik Formation. They described the distribution of the 

formation and the stratigraphic relations, lithology, and age 

based on megafossils of the section. C. reidae is included to 

indicate that the accretionary terranes may contain entirely 

different Triassic ostracode assemblages. 

Age of the Ostracodes 

Silberling (Detterman and others, 1975, p. 15, fig. 6; 

p. 43) recorded Daonellaframi Kittl and Leiophyllites sp. in 

the basal siltstone member of the Shublik Formation at the 

reference section. USGS colin. M6052, collected from 8.2 

to 21.9 meters (27-72 feet) above the base of the Shublik 

Formation, indicates an Anisian or Ladinian age. Only a 

small carapace of Ogmoconcha tailleuri (USNM 389916) 

was recovered from the siltstone member of the Shublik 

Formation at 25.9 m (85 ft) above the base of the Shublik 

Formation (USGS colln. 33106). 

The lower part of the overlying limestone and dolomite 

member of the Shublik Formation yielded most of the ostracodes. The majority occurred from approximately 30 to 70 

m (100-235 ft) above the base of the formation. Based on 

the megafossils, this interval is Ladinian in age. USGS 

colin. M6054 from the limestone and dolomite member, 

30.5 m (100 ft) above the base of the Shublik Formation, 

contains Daonella frami Kittl, and USGS colln. M6053 in 

the same member, 30.5 to 33.5 m (100-110 ft) above the 

base of the Shublik Formation, contains D.frami, Lima sp., 

Camptonectes sp., and spiriferoid brachiopods; these indicate a Ladinian age for this interval. Only three ostracode 

taxa, Covracythere gryci n. sp., 0. sp. aff. 0. owthropensis 

(Anderson, 1964), and 0. tailleuri n. sp. extend above this 

interval into the Norian. The ostracodes from 30.5 to 70 m 

(100-230 ft) must be Ladinian because of the associated 

megafossils. 

The middle part of the section, the limestone member of 

the Shublik Formation, from approximately 69 m (225 ft) to 

approximately 97 m (320 ft) above the base of the Shublik 

Formation is Carnian in age. Silberling (Detterman and 

others, 1975, p. 15, fig. 6, p. 43) recorded the following 

Carnian megafossils from USGS colln. M6056, from 68.6 

to 71.6 m (225-235 ft) above the base of the Shublik Formation in the limestone member: Halobia cf. H. zitteli Lindstrom, Leptochondria nationalis Smith, Gryphea sp., Lima 

sp. , arcetid ammonites, rhynchonellid brachiopods, and 

gastropods. In USGS colln. M6057, from about 74 to 97 m 

(245-320 ft) Silberling recorded the following Carnian 

megafossils: Halobia cf. H. zitteli Lindstrom, H. ornatissima, and Sirenites sp. Only Pseudobythocypris? sp. is 

restricted to this interval. 

The overlying clay shale member of the Shublik Formation, from approximately 106 to 145.5 m (350-477 ft) 

above the base of the Shublik Formation is Norian in age 

based on the megafossils from the upper part of this member, from about 127m (420ft) above the base of the Shublik 

Formation. Siberling (Detterman and others, 1975, p. 16, 

45) recorded the following megafossils in USGS collns. 

M6058, M6059, and M6067: Halobia cf. H. fallax Mojsisovics, H. cf. H. lineata Mojsisovics, Monotis scutiformis 

pinensis Westermann, M. cf. M. scutiformis Westermann, 

M. cf. M. obtusicostata, Gryphea sp. and rhynchonellid 

brachiopods. Of the eight ostracode taxa recovered from the 

Norian, Ogmoconcha marquardti n. sp., 0. alaskaense n. 

sp., Hiatobairdia? sp. ex gr. H. arcuata Kristan-Tollmann, 

1970, Triassocypris? sp., and Gen. and sp. indet. are confined to this unit; the other three taxa extend upward from 

the Ladinian. 

The Triassic ostracodes described from northeastern 

Alaska are new species, taxa tentatively referred to related 

or known Triassic species, or undescribed species discussed 

and illustrated in open nomenclature. Except for Dettermania n. gen., Ogmoconcha Triebel, 1941 [originally described from the Liassic (Lower Jurassic)], and Pseudobythocypris Shaver, 1958 (previously known from the 

Paleozoic), all the taxa are related to genera known from the 

Middle And Upper Triassic Marine Ostracoda, Northeastern Alaska C3 
Primor'ye Province from the Pacific Ocean Zoogeographical Region (Burij and Zharnikova, 1977, p. 90-92) or from 

the Tethyan Zoogeographical Region, as shown in table 1. 

Paleogeographic Implications 

The affinity of the ostracodes in northeastern Alaska with 

those in the Primor'ye Territory (table 2) poses a paleogeographical problem. Tozer (1982) based a model for the 

Triassic paleogeography on plate tectonics, paleomagnetics, 

and paleontology. The upper map of Tozer (1982, p. 1094-

1095, fig. 2) represents the Triassic, and the lower map as 

well as a large scale map (Tozer, 1982, p. 1083, fig. 1) 

show the current world geography. The paleogeographic 

model shows the paleopacific (Panthalassa) to contain scattered shoals and islands. Plate-bound areas on Tozer's maps 

of the present are shown to include northeastern Alaska, 

where the ostracodes were collected. The Triassic model 

shows the Primor'ye Territory as part of a midpaleolatitude, 

about 40°N. of the Triassic equator (Tozer, 1982, p. 1086), 

Table 1. Stratigraphic occurrences of taxa in Alaska 

Taxa Ages 

Ladinian Carnian Norian 

Covracythere binoda n. sp. 

Recytella sp. 1 

Recytella sp. 2 

Dettermania truncata n. sp. 

"Healdia" sp. 1 

"Healdia" sp. 2 

Rhombocythere? sp. 

Ogmoconcha? sp. aff. Hungarella limbata (Reuss, 

1868) 

Cavussurella? sp. 1 

Cavussurella? sp. 2 

Ogmoconcha unicerata n. 

sp. 

Ogmoconcha tailleuri n. sp. 

Covracythere gryci n. sp. 

Ogmoconcha sp. aff. 0. 

owthropensis (Anderson, 

1964) 

"Healdia" sp. 3 

Cavussurella grammi n. sp. 

Pseudobythocypris? sp. 

Ogmoconcha marquardti n. 

sp. 

Ogmoconcha alaskaense n. 

sp. 

Hiatobairdia? sp. ex gr. H. 

arcuata Kristan-Tollmann, 1970 

Triassocypris? sp. 

Gen. and sp. indet. 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

X 

C4 Shorter Contributions to Paleontology and Stratigraphy 

X 

X 

X 

X 

X 

X 

X 

X 

Table 2. Paleozoogeographical provinces and ages of related 

taxa 

[Provinces: *=Primor'ye, **=Tethyan, ***=Britain and Germany] 

Taxa 

Cavussurella grammi n. sp 

Covracythere binoda n. sp. 

"Healdia" sp. 1 

"Healdia" sp. 2 

"Healdia" sp. 3 

Cavussurella grammi n. sp. 

Covracythere gryci n. sp. 

Cavussurella? sp. 1 

Cavussurella? sp. 2 

Recytella sp. 1 

Recytella sp. 2 

Ogmoconcha? sp. aff. 

Hungarella limbata 

(Reuss, 1868) 

Ogmoconcha unicerata n. 

sp. 

Rhombocythere sp. 

Pseudobythocypris? sp. 

Ogmoconcha tailleuri n. 

sp. 

Ogmoconcha sp. aff. 0. 

owthropensis (Anderson, 

1964) 

Hiatobairdia? sp. ex gr. H. 

arcuata KristanTollmann, 1970 

Ogmoconcha alaskaense n. 

sp. 

Triassocypris? sp. 

Ogmoconcha marquardti n. 

sp. 

Age 

*Upper Anisian 

Do. 

*Upper Anisian 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

*Ladinian 

Do. 

**Lower Carnian 

Do. 

**Norian-Rhaetian 

Do. 

***Rhaetian 

Do. 

**Rhaetian 

Do. 

Do. 

Do. 

volcanic terrane that later became part of Japan and part of 

Asia (Tozer, 1982, p. 1095, fig. 2, no. 18). Blome and 

Reed (oral commun. , 1984) reported that some of the Triassic radiolarians in the Brooks Range, Alaska, are related on 

the generic level to those in Japan. 

A different model for the Triassic faunal relation was 

proposed by Kristan-Tollmann and Tollmann (1981, fig. 1; 

1983, fig. 9). They considered the Triassic Pacific Ocean as 

a gigantic ocean without any islands in which a major paleocurrent, the "Tethys current," transported the Triassic fauna 

from the west coast of North America to the Mediterranean 

(Tethyan) Zoogeographical Province. 

Neither model explains the similarity on the generic level 

of the ostracodes in northern Alaska to those in the 

Primor'ye Territory. A combination of the above models 

may explain more closely the similarities. Although Tozer 

(1982) did not discuss paleocurrents, currents in the Triassic 

certainly influenced the distribution of marine organisms 

(Choi, 1984, p. 731). If the paleocurrent patterns proposed 

by Kristan-Tollman and Tollmann (1981) were modified, 

reflecting the presence of the various islands and shoals, the 
new model could explain the similarity on the generic level 

shown in table 2. 

Burij and Zhamikova (1977) used the Jaccard coefficient 

in the analysis of Triassic ammonite genera to determine 

paleozoogeographic provinces. They distinguished two latitudinal zoogeographic provinces in the northern Pacific 

Basin: a northern, colder, Y akutian-Canadian (including 

northern Alaska) subregion in the Boreal Zone and a warmer 

Primor'ye-Californian subregion in the Equatorial Zone. 

During the early Middle Triassic (Anisian), the Yakutian 

province was connected closely with the Primor'ye province 

(Burij and Zhamikova, 1977, p. 102). During the Ladinian, 

the Y akutian and Canadian provinces (including northern 

Alaska) were interconnected (Burij and Zhamikova, 1977, 

p. 104). Paleocurrents during the Anisian could have distributed the Primor'ye taxa described by Gramm (1969a, b, 

1970, 1975) into the Yakutian province, and, during the 

Ladinian, paleocurrents could have transported those taxa 

into the area of northeastern Alaska. 

Environment of the Ostracodes 

The genera to which the taxa in northeastern Alaska are 

assigned indicate a benthic life style, probably less than 200 

min depth. Dutro (1981, p. 25) proposed that the Shublik 

Formation was deposited in relatively deep water far from 

shore. He based his conclusions on the fact that the sediments consist of thin-bedded phosphatic limestone, shale, 

and chert. According to Dutro, the Shublik Formation represents a comparatively long period of time in which very little 

sediment was deposited. 

Burij and Zhamikova (1977) considered Alaska to be 

located in a Boreal Paleozoogeographical Province. The 

presence in Alaska of taxa related on the generic level (table 

2 ) to forms originally described from Britain and northern 

Germany that were connected to the Boreal Sea (Fisher, 

1984) supports their interpretation. 

The ostracode assemblage in northeastern Alaska differs 

markedly on the generic level from the ostracodes in the 

Lewes River Formation (Norian), Yukon Territory, Canada. 

This formation contains Cornutobairdia reidae n. sp., described herein, and undescribed taxa tentatively referred to 

the following genera: Acratia Delo, 1930, Paleozoic 

through Upper Triassic; Alatobairdia Kristan-Tollmann, 

1971b, Rhaetian; Bairdia McCoy, 1844, smooth type, Paleozoic through Holocene; Bairdiacypris Bradfield, 1935, Paleozoic through Rhaetian; Carinobairdia Kollmann, 1963, 

Norian through Rhaetian; Ceratobairdia Sohn, 1954 sensu 

Kristan-Tollman, 1970, Permian through Rhaetian; Leviella 

Sohn, 1968, Anisian through Rhaetian; Lobobairdia Kollmann, 1963, Norian through Rhaetian; Polycopsis Muller, 

1894, Scythian through Holocene; Ptychobairdia Kollmann, 1960, Norian through Rhaetian; Vavilovella Kozur, 

1973, Norian; and additional, as yet unidentified, taxa. 

THE HUNGARELLA-OGMOCONCHA PROBLEM 

TheHungarella-Ogmoconcha problem was created when 

Mehes (1911 , p. 21 , pl. 2. figs. 14-18) described Bairdia ? 

problematica and stated (p. 22) that if subsequent investigations determined that the species belonged to a new genus, 

that genus should be named in the literature as Hungarella. 

The original description of Bairdia? problematica (Mehes, 

1911, p. 21, 22) stated that the valves were very well preserved and not thick, were completely glassy, and were 

transparent. The above description suggests a Holocene or 

Tertiary contamination, either in the field or in the laboratory, of some of the collections that Mehes studied. 

Triebel (1941 , p. 3 77) described and illustrated with excellent photographs the genus Ogmoconcha from the Liassic 

of Germany. Shaver (Moore, 1961, p. Q161), van 

Morkhoven (1963, p. 132), and Anderson (1964, p. 146) 

considered Ogmoconcha to be a junior subjective synonym 

of Hungarella because conditional names, such as Hungarella, were declared valid according to Article 17(8) in 

the second edition of the International Code of Zoological 

Nomenclature [Stoll and others, 1961, p. 17; article 5lc (ii) 

of the third edition (International Commission on Zoological 

Nomenclature, 1985, p. 97)]. Sohn (1968, p. 28) discussed 

the differences between Ogmoconcha and Hungarella 

Mehes, 1911. Since that time, the Hungarella-Ogmoconcha problem has been discussed by Kozur (1970b, p. 20), 

Bolz (197lb, p. 156, 243), Malz (1971, p. 434), Lord 

(1972, p. 332; 1982, p. 262), Gerry and Kozur (1973, p. 

67-69), Kristan-Tollmann (1977, p. 133, 142, 143), and 

Bate (1978, p. 186). Except for Lord (1972, p. 352), the 

above writers did not take into account the possibility that 

Mehes included younger contaminants in his faunule (Mandelstam, 1960, footnote p. 292; Sohn, 1968, p. 39; Tappan, 

1951, p. 7; Vadasz, 1933, p. 173). Lord (1982, p. 262) 

considered the relationship of Ogmoconcha and Hungarella 

to be unresolved until topotype material of Hungarella 

would be restudied and reillustrated. 

The basic problem involves the presence or absence of a 

calcified inner lamella (duplicature), a denticulate hinge, 

and an aggregate, so-called healdiid, adductor muscle scar 

in Hungarella. An aggregate adductor muscle scar has been 

described in Ogmoconcha and also in the original and subsequent descriptions of Hungarella . Gerry and Kozur (1973, 

p. 67-69) reported that they examined a "cell" containing 

type material of Mehes ( 1911) at the Hungarian Geological 

Institute and noted the following regarding Hungarella 

"Bairdia"? problematica Mehes, 1911: "Syntype T685 

AFL Ladinian, Felsors. Destroyed, some badly preserved 

fragments showing no calcified inner lamella. (Generotype 

of Hungarella! !)" 

My experience with ostracode types (Zalanyi, 1959) at 

the Hungarian Geological Survey may provide a plausible 

explanation as to the condition of the types of Hungarella. 

I saw Zahinyi' s Aptian types at the Hungarian Geological 

Middle And Upper Triassic Marine Ostracoda, Northeastern Alaska C5 
Institute, Budapest, on August 10, 1976. All the specimens 

were on one large, plastic, multicelled slide that was covered by similar material attached at the comers with tiny 

screws. The cover was inscribed with a grid covering each 

cavity so that the species in each cavity was identified by 

coordinates written in a notebook. I recognized in this multicelled slide that the specimen in the cavity identified as 

Metacypris aculeata Zalanyi, 1959, was not that species, 

and I saw many specimens, some crushed, that had moved 

into neighboring cavities with time and handling since Boda 

( 1964) published his catalogue of Hungarian fossils. It is 

possible that the fragments examined by Gerry and Kozur 

(1973. p. 67, 69) in the Bairdia? problematica cavity may 

have had a similar history and belong to a different species, 

or they may represent different specimen than the one illustrated by Lord (1972, pl. 1, figs. la, b) with the same 

catalog number. Lord (1972, p. 321) stated that his illustration was provided by the Hungarian Geological Institute. 

Hungarella? pricei Sohn, 1968, from the Ladinian of 

Israel, and Hungarella? sp. Sohn, 1970, from the Early 

Triassic of the Salt Range, West Pakistan, have calcified 

inner lamellas and denticulate hingements (Sohn, 1968, p. 

29, pl. 2, figs. 28, 29, text fig. 3; 1970, p. 204, pl. 1, figs. 

41, 42). Mehes (1911, p. 21) did not record a denticulate 

hinge in the type species, Bairdia? problematica , nor in the 

second taxon, B.? problematica var. reniformis. He did 

mention that two specimens of the variety reniformis have 

a strong ventroposterior spine. Kozur (1970a, p. 22, pl. 4, 

figs. 15-17) described and illustrated Healdia (Hungarella) 

reniformis (Mehes, 1911), from the Anisian and Ladinian of 

Hungary, and stated that the hinge is not denticulate 

("Schlosselemente glatt"). 

Dr. 1. Fiilop, Director of the Hungarian Geological Survey, mailed me some washed samples from the Triassic of 

Hungary, including one from the Carnian marl that is equivalent to locality no. 5 of Mehes (USGS colln. 33172). He 

informed me (written commun., June 22, 1966) that it was 

(and still may be) impossible to collect at the localities 

studied by Mehes. Specimens with a posteroventral spine 

and a denticulated hinge are present in the collection, and 

one is illustrated herein as Ogmoconcha sp. (pl. 10, figs. 12, 

13; Sohn, 1984b, fig. liE-G). Other specimens in the collection have thick valves and are opaque, and the adductor 

muscle scar could not be discerned even after treatment with 

hydrofluoric acid (pl. 11, figs. 13-16, 20--23). 

A "healdiid" adductor muscle scar combined with a denticulate hinge were illustrated by Gramm (1982, p. 198, text 

figs. 6-8; pis. 2-5) for the Lower Carboniferous genus 

Healdianella Posner, 1951. Anderson (1970, fig. 1) and 

Sohn (1977, fig. lb; 1985, figs. 2.3, 2.7, 2.10, 2.14, 3.18) 

illustrated a similarly aggregate adductor muscle scar for the 

nonmarine genus Carbonita Strand, 1928, that does not 

have a denticulate hinge. The number of individual adductor 

muscle scars in the living Darwinula stevensoni (Brady and 

Robertson, 1870) is not related to growth stages and may 

C6 Shorter Contributions to Paleontology and Stratigraphy 

vary in opposite valves of the same individual (Sohn, 1976, 

p. 305). The "healdiid" adductor muscle scar is clearly 

developed in several different groups of Ostracoda; consequently, the "healdiid" pattern should not be used as the sole 

criterion for generic determination. To validate Hungarella 

Mehes, 1911, a neotype should be selected from the Hungarian Triassic, and the genus should be redefined, because, 

based on the present information, the taxon should be considered a nomen dubium. 

USGS MESOZOIC FOSSIL COLLECTION 

LOCALITIES 

[All collections measured from base of Shublik Formation, conversion of feet to meters to the nearest 0.1 m. Measured reference section of the Shublik Formation (Detterman and others, 

1975, p. 14, fig. 6), located 13.4 km (6.3 mi) 84°W. of the 

confluence of Fire Creek with the Sadlerochit River, Mount 

Michelson quadrangle, Alaska; lat. 69°31' 45"N ., long. 

145°12'20"W. Collected by R. L. Detterman, field station 69 

ADT 105] 

Siltstone Member (Anisian and Ladinian) 

33106. 25.9 to 27.4 m (85-90 ft). Field no. 3-3. 

Limestone and Dolomite Member (Ladinian) 

33107. 30.5 to 32.0 m ( 100-105 ft). Field no. 3-6. 

33108. 32.0 to 33.5 m ( 105-110 ft). Field no. 3-7. 

33109. 33.5 to 35. I m ( 110-115 ft). Field no. 3-8. 

33110. 35.1 to 36.6 m ( 115-120 ft). Field no. 3-9. 

33111. 36.6 to 38.1 m ( 120-125 ft). Field no. 3-10. 

33112. 38.1 to 39.6 m (!25-130 ft). Field no. 3-11. 

33113. 39.6 to 41.1 m ( 130-135 ft). Field no. 3-12. 

33114. 41.1 to 42.7 m ( 135-140 ftl. Field no. 3-13. 

33115. 42.7 to 44.2 m ( 140-145 ft). Field no. 3-14. 

33116. 44.2 to 45.7 m ( 145-150 ft). Field no. 3-15. 

33117. 45.7 to 47.2 m ( 150-155 ft). Field no. 3-16. 

33118. 47.2 to 48.8 m ( 155-160 ft). Field no. 3-17. 

33119. 48.8 to 50.3 m ( 160-165 ft). Field no. 3-18. 

33120. 50.3 to 51.8 m ( 165-170 ftl. Field no. 3-19. 

33121. 51.8 to 53.3 m ( 170-175 ft). Field no. 3-20. 

33122. 53.3 to 54.8 m ( 175-180 ftl. Field no. 3-21. 

33123. 54.8 to 56.4 m ( 180-185 ft). Field no. 3-22. 

33124. 56.4 to 57.9 m ( 185-190 ft). Field no. 3-23. 

33125. 57.9 to 59.4 m ( 190-195 ft). Field no. 3-24. 

33126. 59.4 to 61.0 m (! 95-200 ft). Field no. 3-25. 

33127. 61.0 to 62.5 m (200-205 ftl. Field no. 3-26. 

33128. 62.5 to 64.0 m (205-210 ft). Field no. 3-27. 

33129. 64.0 to 65.3 m (210-215 ft). Field no. 3-28. 

33130. 65.3 to 67.1 m (215-220 ft). Field no. 4-1. 

33131. 67. I to 68.6 m (220-225 ft). Field no. 4-2. 

Limestone Member (Carnian) 

33132. 68.6 to 70.1 m (225-230 ft). Field no. 4-3. 

33133. 82.2 to 83.8 m (27-275 ft). Field no. 5-9. 

33134. 83.8 to 85.3 m (27-280 ft). Field no. 5-10. No 

ostracodes recovered. 
33135. 85.3 to 86.9 m (280-285 ft). Field no. 5-11. No 

ostracodes recovered. 

33136. 86.9 to 88.4 m (285-290 ft). Field no. 5-12. 

33137. 88.4 to 89.9 m (290-295 ft). Field no. 5-13. 

33138. 89.9 to 91.4 m (295-300 ft). Field no. 5-14. No 

ostracodes recovered. 

33139. 91.4 to 93.0 m (300-305 ft). Field no. 5-15. No 

ostracodes recovered. 

33140. 93.0 to 94.5 m (305-310 ft). Field no. 5-16. 

33141. 94.5 to 96.0 m (310-315 ft). Field no. 5-17. 

33142. 96.0 to 97.5 m (315-320 ft). Field no. 5-18. 

33143. 97.5 to 99.1 m (320-325 ft). Field no. 5-19. 

Clay Shale Member (Norian) 

33144. 106.7 to 108.2 m (350-355 ft). Field no. 6-6. 

33145. 108.2 to 109.7 m (360-365 ft). Field no. 6-7. 

33146. 109.7 to 111.3 m (360-365 ft). Field no. 6-8. 

33147. 111.3 to 112.8 m (365-370 ft). Field no. 6-9. 

33148. 112.8 to 114.3 m (370-375 ft). Field no. 6-10. 

33149. 114.3 to 115.8 m (375-380 ft). Field no. 6-11. 

33150. 115.8 to 117.3 m (380-385 ft). Field no. 6-12. 

33151. 117.3 to 118.9 m (385-390 ft). Field no. 6-13. 

33152. 118.9 to 120.4 m (390-395 ft). Field no. 6-14. 

33153. 120.4 to 121.9 m (395-405 ft). Field no. 6-15. 

33154. 121.9 to 123.4 m (400-405 ft). Field no. 6-16. 

33155. 123.4 to 125.0 m (405-410 ft). Field no. 6-17. 

33156. 125.0 to 126.5 m (410-415 ft). Field no. 6-18. 

33157. 126.5 to 128.0 m (415-420 ft). Field no. 6-19. 

33158. 128.0 to 129.5 m (420-425 ft). Field no. 6-20. 

33159. 129.5 to 131.1 m (425-430 ft). Field no. 6-21. 

33160. 131.1 to 132.6 m (430-435 ft). Field no. 6-22. 

33161. 132.6 to 134.1 m (435-440 ft). Field no. 6-23. 

33162. 134.1 to 135.6 m (440-445 ft). Field no. 6-24. 

33163. 135.6 to 137.2 m (445-450 ft). Field no. 6-25. 

33164. 137.2 to 138.7 m (450-455 ft). Field no. 6-26. 

33165. 138.7 to 140.2 m (455-460 ft). Field no. 6-27. 

33166. 140.2 to 141.7 m (460-465 ft). Field no. 6-28. 

33167. 141.7 to 143.3 m (465-470 ft). Field no. 6-29. 

33168. 143.3 to 144.8 m (470-475 ft). Field no. 6-30. 

33169. 144.8 to 145.4 m (475-477 ft). Field no. 6-31. 

Other localities 

33170. South side of Lime Peak, about 300 m above level 

of Lake Thomas, 60°04'24"N. , 134 °51' 6"W. , 

Whitehorse Trough, Yukon Territory, Canada. Interreef limestone beds in the Lewes River Formation, Norian. Collected by Pamela Reid, field no. 

R-80-b. 

33171. North side of Lime Peak, about 450 m above 

Thomas Lake (on south side of peak), and 250 m 

above ponds in valley on north side, 61°04'02"N., 

134°53'42"W. Collected by Pamela Reid, field no. 

R-39-8. 

33172. Lower Carnian marl from Csopak, Neszteri Valley, 

Hungary, corresponds to that of locality no. 5 

studied by Mehes (1911). Sent by Dr. J. Fiilop, 

Director, Hungarian Geological Survey, June 1966. 

SYTEMATIC PALEONTOLOGY 

Except those illustrated specimens deposited in the geological Survey of Canada, Ottawa (GSC), all specimens are 

deposited in the National Museum of Natural History, 

Washington, D.C. (USNM). 

Order PODOCOPIDA Sars, 1866 

Suborder BAIRDIOCOPINA Griindel, 1967 

Superfamily BAIRDIACEA Sars, 1888 

Family BAIRDIIDAE Sars, 1888 

Subfamily BAIRDIINAE Sars, 1923 

Genus HIATOBAIRDIA Kristan-Tollmann,1970 

Hiatobairdia Kristan-Tollmann, 1970, p. 285. Rhatean, 

Austria. 

Type species.-H. subsymmetrica Kristan-Tollmann, 

1970, p. 286, pl. 35, figs. 1-3. 

Discussion.-Kristan-Tollmann (1970, p. 286-289) described three species in H iatobairdia: H. subsymmetrica 

based on seven specimens and H. labrifera and H. arcuata 

based on a single specimen each. I doubt whether the three 

species are congeneric. Because I have only three small 

steinkems, I do not have sufficient information to establish 

a new generic category; consequently, I am referring them 

to Hiatobairdia? sp. ex gr. H. arcuata. 

Geologic range.- Upper Triassic. 

Geographic distribution. -Known from Europe, and 

?northeastern Alaska. 

Hiatobairdia? sp. ex gr. H. arcuata 

Kristan-Tollmann, 1970 

Plate 2, figures 18, 19 

Hiatobairdia arcuata Kristan-Tollmann, 1970, p. 288, pl. 

35, fig. 5. Rhaetian, Austria. 

Hyatobairdia sic. sp. ex gr. H. arcuata Kristan-Tollmann, 

1970. Sohn 1984b, p. 21 figure 11H. 

not Bairdia arcuata (Kristan-Tollmann, 1970). Bolz, 

1971a, p. 170, pl. 6, figs. 65-67. Differs in lateral outline. 

not Hiatobairdia aff. H. arcuata Bolz, 1971b, pl. 1, fig. 6. 

Discussion.-The three small steinkems resemble H. arcuata in lateral outline and in that both ends curve upwards; 

they differ in that the ventral margins are convex instead of 

straight, and the greatest width is above the midheight instead of below the midheight. 

Measurements (in mm).-USNM 389814, greatest 

length, 0.50, greatest height 0.30; measured specimen, 

USNM 389815, greatest length 0.45, greatest height 0.30; 

measured specimen, USNM 389816, greatest height 0.42, 

greatest height 0.35. 

Geologic range.- Norian, from 112.0 to 140.9 m (370-

465 ft) above the base of the Shublik Formation. 

Genus CORNUTOBAIRDIA Kristan-Tollmann, 1970 

Cornutobairdia Kristan-Tollman, 1970, p. 303. 

Triebelina (Triebelina) van den Bold, 1946, ofBolz, 1971a, 

p.183. 

Middle And Upper Triassic Marine Ostracoda, Northeastern Alaska C7 
Type species.-C. reticulata Kristan-Tollmann, 1970, 

p. 305, pl. 37, figs. 4-6. Rhaetian, "Plackles," Austria. 

Original diagnosis (translated).-"Carapace elongated, 

strongly to moderately sculptured with three more or less 

elongated elements of which the two outer may join into a 

ring. The sculpture of both valves is different, in that the 

dorsal area of the left valve differs from the right; the left 

has additional strong sculpture, that expands into knobs and 

spines particularly in the posterodorsal area (compare generotype). In addition, the complete carapace is covered by 

a netforming pitted sculpture. The hinge is a simple, smooth 

bairdiid hinge terminated by numerous toothlets." 

Discussion. -Kristan-Tollmann illustrated the type species with drawings of two carapaces that are dimorphic in 

width of dorsal and ventral outlines (1970, pl. 37), figs. 

4a-d, 5a-d) and the hingement of a right valve (1970, pl. 

37, figs. 61, b). She referred to C. reticulata a specimen 

from the same locality, illustrated by Kollmann as Triebelina sp./498 with photographs of the inside and outside of a 

right valve (Kollmann, 1963, 1979, pl. 8, figs. 11 , 13). 

Kristan-Tollmann (1970, p. 306) stated that the right valve 

illustrated in outside view by Kollmann (1963, p. 1979, pl. 

8, fig. 12) as Triebelina sp. 158 represents an additional 

species in this genus and illustrated a juvenile left valve 

(Kristan-Tollmann, 1970, pl. 37, fig. 3a, b) as Cornutobairdia n. sp. from the Rhaetian Zlambachmergeln at Krautgartenalm, Austria. Kristan-Tollmann (1971b, p. 77, pl. 5, 

figs. 4, 5) referred the above specimen to C. trinodosa 

Kristan-Tollmann, 1971b. Bolz (1971a, p. 720) considered 

the above specimen as the A-3 stage of Triebelina sp./158 

Kollmann, 1963, and illustrated a right valve of C. reticulata (Bolz, 1971b, p. 721, pl. 2, fig. 12). Bolz (1971a, 

p. 184, pl. 9, figs. 122-126, text fig. 24) considered Cornutobairdia a synonym of Triebelina and referred all the 

above taxa except C. trinodosa to Triebelina (Triebelina) 

reticulata (Kristan-Tollmann, 1970), republished his 

plate 2, figure 12 as plate 9, figure 124, and recorded the 

range of the species as Upper Norian- ?Liassic. Kozur 

(1972a, p. 652, pl. 2, fig. 2) republished Bolz's (1971b) 

plate 9, figure 122, as "Triebelina reticulata" and included 

Bolz' s photograph on a plate illustrating a shallow neritic 

Upper Norian ostracode assemblage. 

Bolz (1971a, p. 176-183) reviewed the literature on 

Triebelina van den Bold, 1964, and constructed a table 

showing characters of species in that genus. All the species 

of Tertiary to present ages, except Triebelina schulzi Hartmann, 1964, are from 0.59 to 0.75 mm in greatest length. 

The living T. schultzi Hartmann, 1964, is recorded to be 

1.04 mm in greatest length, and the species is smooth (Hartmann, 1964, p. 44, pl. 4, fig. 14) and has a denticulated 

hinge (Hartmann, 1964, p. 45, pl. 4, figs. 20, 21); consequently, T. schulzi should not be classified with either 

Triebelina or Cornutobairdia. Van Morkhoven (1963, 

p. 35) recorded the length of species in Triebelina to be from 

C8 Shorter Contributions to Paleontology and Stratigraphy 

0.6 to 0. 9 mm. Specimens of Cornutobairdia are larger than 

1.0 mm (Bolz, 1971b, text figs. 23, 24), and all the species 

described in the genus have a dorsoposterior hom on the 

larger valve or on both valves, a feature not recorded in 

Triebelina. Cornutobairdia, although related to Triebelina, 

is considered a valid genus for the above reasons. 

Combining the two taxa masks the stratigraphic utility of 

both genera. The following species are known: 

Cornutobairdia bicornuta Kristan-Tollmann, 1979, p. 153, 

pl. 7, fig. 4; pl. 8, fig. 4, Rhaetian, Persia. 

C. reidae n. sp., Norian, Canada. 

C. reticulata Kristal-Tollmann, 1970, p. 305, pl. 37, figs. 

4-6, Upper Norian-?Liassic, Austria. 

C. trinodosa Kristen-Tollmann, 1971b, p. 77, figs. 4, 5, 

Upper Norian-Austria. 

Geologic range.- Upper Norian-?Liassic. 

Geologic distribution.-Known from Europe and North 

America. 

Cornutobairdia reidae Sohn, n. sp. 

Plate 3, figures 1-6 

Etymology ofname.-In honor of Ms. Pamela Reid, University of Miami, who collected the samples that contain 

this species. 

H olotype.-GSC 80063. 

Paratypes.-GSC 80064-80066, USNM 389830-

389834. 

Type locality.-Southem slope of Lime Peak, Yukon 

Territory, Canada, USGS colin. 33170. 

Other locality.- Northwest slope of Lime Peak, Yukon 

Territory, Canada, USGS colin. 33171. 

Type level.-Lewes River Formation, Norian, USGS 

colln. 33170. 

Diagnosis.-Cornutobairdia with two subcentral nodes, 

dorsal margin of the larger valve with upward-trending 

spine near anterior and dorsolateral trending spine near posterior, minute spine lets on anterior and ventroposterior margins. Reversal of overlap and hingement present, but mostly 

left valve larger. 

Description.-The shells are heavily calcified, asymmetrical; larger valve overreaches the smaller along a straight 

dorsal hinge, overlaps slightly along the gently convex ventral margin. The surface of the larger valve bears a large 

node at or slightly below midheight in front of the greatest 

length of the hingeline and a second, smaller node located 

slightly higher than the subcentral node about equidistant 

from the hingeline and dorsoposterior margin. The dorsoposterior margin is obtuse, with about 130° angle from the 

posterior end of the hingeline, extends backward to about 

three-fourths of the height or below the posterior node, and 

then points to the rear to form a posterior spine; it then 

curves gently forward to meet the gently convex ventral 

margin. The anterior margin is subround, the dorsoanterior 

is straighter than the dorsoposterior. A rounded rim borders 
the ventral and anterior margins and continues above the 

dorsal margins as a spine (pl. 3, figs. 2, 3, 6). From this 

spine, a straight, narrower ridge extends backwards to the 

posterior comer where it forms a posterolateral-pointing 

sharp spine. Above the dorsal ridge, the dorsal margin forms 

a pleatlike: ridge that bends inward to overreach the hingeline (pl. 3, figs. 2, 5). 

The smaller valve has two nodes and a rounded rim along 

the ventral and anterior margins as well as along the posteroventral margin but lacks the dorsal spines and the pleatlike overreaching structure of the larger valve. The anterior 

and ventroposterior margins bear minute spinelets (pl. 3, 

figs. 4, 5). The duplicature is wide along the anterior margin, narrow or missing along the posterior margins on both 

valves. 

Measurements (in mm).-Width measured on subcentral 

nodes. USNM 389831 contains seven specimens, USNM 

389832 contains two specimens. R. V. = right valve, 

L. V. = lt!ft valve).-

GSC 80063, larger R. V. 

GSC 80064, smaller R. V. 

GSC 80065, larger L. V. 

GSC 80066, larger L. V. 

Paratype, USNM 389830, 

larger L. V. 

Paratypes, USNM 389831, 

larger L. V. 

Paratype, USNM 389833, 

larger L. V. 

Greatest 

length 

1.10 

1.05 

1.04 

.96 

1.00 

1.0-1.20 

1.05 

Greatest 

height 

0.65 

.50 

.63 

.50 

.50 

.53-.64 

.61 

Greatest 

width 

0.52 

.45+ 

.45 

Discussion.-The ostracodes are silicified, many are 

poorly preserved, and the adductor muscle scar is not observed. The marginal spines can be seen on the single valve 

(pl. 3, figs. 4, 5). This species is associated with specimens 

on which the subcentral nodes coalesce to form a ridge 

(USNM 389835, 389836) similar to those illustrated by 

Bolz (1971b, pl. 9, figs. 122-126) as Triebelina (Triebelina) reticulata (Kristan-Tollmann, 1970) = Cornutobairdia. A few specimens have three distinct nodes in a straight 

line, with or without the posterior node extending into a 

lateral spine (USNM 389836). These variants are not yet 

available in sufficient numbers for a population study to 

determine whether they represent one or more species. They 

are, however, distinct from C. reidae because the posterior 

node in the new species is located higher on the lateral 

surface than the subcentral node, and, on the variants, more 

than two nodes occur in a straight line. 

Geologic range.- Known only from the two collections 

from the L.ewes River Formation (Norian) in the Yukon 

Territory, Canada. USGS collns. 33170, 33171. 

Suborder unknown 

Superfamily unknown 

?Family PARACYPRIDIDAE Sars, 1923 

Genus TRIASSOCYPRIS Kozur, 1970 

Type species.-Macrocypris? pusilla Kozur, 1968b, 

p. 500, pl. 2, figs. 14, 20-27. Lower and Middle Triassic, 

Thuringia. 

Diagnosis (translated).-"Carapace small, right valve 

larger than left; dorsal margin convex, not angled; posterior 

margin pointed; ventral margin almost straight. Shell surface smooth. Hinge adont. Calcified inner lamella and 

vestibule wide in front, otherwise narrow." 

Kozur assigned to this genus the holotype T. pusilla 

(Kozur, 1968b) and T. tenuis (Kozur, 1968b), both originally described as Macrocypris?. 

Discussion.-Kozur (1970b, p. 445) referred Triassocypris to the Paracyprididae. The Paracyprididae were defined in Moore (1961, p. Q245) as having a wide duplicature and large anterior and posterior vestibules. 

Triassocypris has a wide anterior and a narrow posterior 

vestibule and probably should not be classified in the Paracyprididae. 

Geolgoic range.-Triassic. 

Geographic distribution.-Known from Europe and, 

questionably, from northeastern Alaska. 

Triassocypris? sp. 

Plate 11 , figures 1-4 

Discussion.-The Upper Triassic specimen from Alaska 

is a poorly preserved carapace with most of the shell probably missing; consequently, the internal morphology of the 

valves is unknown. Because the specimen resembles Triassocypris in lateral outline, I am tentatively referring it to the 

genus. 

Measurements (in mm).-Plate 11, figures 1-4, USNM 

390005, greatest length 0.30, greatest height 0.15. 

Geologic range. -Norian, from 111.3 to 112.8 m (365-

370 ft) above the base of the Shublik Formation. USGS 

colin. 33147. 

Gen. and sp. indet. 

Plate 11 , figures 5, 6 

Discussion.-The illustrated specimen is a poorly preserved carapace from the same collection as Triassocypris? 

sp. It differs in having a less pointed posterior, and the left 

valve apparently overlaps the right. 

Measurements (in mm).-Plate 11, figures 5, 6, USNM 

390006, greatest length 0.27, greatest height 0.15. 

Geologic range .-Norian, from 111.3 to 112.8 m (365-

370 ft) above the base of the Shublik Formation. USGS 

colin. 33112. 

Suborder CYTHEROCOPINA Griindel, 1967 

Superfamily CYTHERACEA Baird 

Discussion. -The adductor muscle-attachment scar illustrated on pl. 2, figs. 22-26, is typical for Cyntheracea. 

Middle And Upper Triassic Marine Ostracoda, Northeastern Alaska C9 
Family COVRACYTHERIDAE n. fam. 

Diagnosis. -Small, less than 1 mm in length, elongated, 

with straight dorsal and gently convex ventral margins, with 

sulcus in front of midlength, two or more horizontal ribs that 

may or may not join at end margins, surface finely punctate 

or smooth. Hingement unknown, hingeline obscured by 

dorsal rib; overlap slight, left over right. Dimorphic in width 

of posterior. 

Discussion. -Gramm (1975) referred Covracythere and 

two additional Triassic genera to the subfamily Editinae 

Kniipfer, 196 7, in the B ythocytheridae S ars, 1926. Although the nominate genus, Editia germanica Kniipfer, 

1967, has a cytheracean adductor muscle-attachment scar, it 

has a well-developed eye tubercle that is not present in 

Covracythere nor the other genera referred herein to the new 

family. Except for the adductor muscle scar, the hingement 

and other internal morphology of Covracythere were unknown to Gramm (1975, p. 108) and are not known for the 

species in Alaska. 

When originally examined, the specimen illustrated on 

plate 7, figures 16-20, was tentatively referred to the Paleozoic family Beyrichiopsidae Sohn (Moore, 1961) because 

of the horizontal ribs (Sohn, 1984b, p. 21, fig. 111). SEM 

micrography, with the carapace tilted, disclosed the cast of 

the horizontal ribs on a specimen with a cytheracean adductor muscle scar (pl. 2, fig. 25), thus placing that specimen 

in the Cytheracea Baird, 1850. The specimens from the 

Triassic differ from Beyrichiopsis Jones and Kirkby, 1886, 

in lacking a marginal frill as shown by Sohn (Moore, 1961, 

p. Q183, fig. 6). The new family is established to include 

the nominate genus, Racvetina Gramm, 1975, Acvocarina 

Gramm, 1975, and, tentatively, Dettermania new genus 

because the aductor muscle scar of the new genus is unknown. 

Geologic range .-Known only from the Middle and 

Upper Triassic. 

Genus COVRACYTHERE Gramm, 1975 

Type species .-Covracythere kiparissovae Gramm, 

1975, p. 108, pl. 1, figs. 23-27, 33. Middle Triassic, Primor'ye Territory. 

Original diagnosis (translated).-"Carapace small, 

nearly rectangular, with dorsal and ventral flattenings, and 

poorly defined transverse depression. Extremities rounded, 

the posterior narrower. Dorsal and ventral margins straight 

and parallel. Surface faintly pitted; a thin looplike ridge 

stretches along the anterior and ventral margins and the 

middle of the surface (parallel to dorsal margin). Adductor 

muscle scar comprises five elongate, obliquely directed 

spots juxtaposed in a vertical row. 

"Assigned species: Only the type species." 

Discussion .-Gramm's illustration of the adductor 

muscle-attachment scar (1975, pl. 1, fig. 33) is identical to 

those illustrated on the species from Alaska (pl. 2, figs. 

20-26). 

Cl 0 Shorter Contributions to Paleontology and Stratigraphy 

Geologic range .-Upper Anisian to Norian. 

Geographic distribution .-Primor'ye Territory, 

U.S.S.R. , and northeastern Alaska. 

Covracythere gryci n. sp. 

Plate 2, figures 20-26; plate 7, figures 16-25 

New genus, n. sp. Sohn, 1984b, p. 21. fig. 111. 

Etymology of name .-In honor of George Gryc, Chief, 

National Petroleum Reserve in Alaska. 

Holotype.-Pl. 7, figs. 23-25, USNM 389824. 

Paratypes .-USNM 389817, 389822, 389823, 389825-

389828, ?389829, ?389940. 

Type level.-Ladinian, from 36.4 to 37.9 m above base 

of Shublick, Formation. 

Other levels.-Norian, from 143.9 to 144.5 m above 

base of Shublik Formation. 

Diagnosis .-Covracythere with three horizontal ribs, 

lower two ribs joined to form elongated ellipse, middle rib 

unbroken across subcentral sulcus, surface finely pitted. 

Description.-The carapace is elongated, the greatest 

length is above midheight, about twice the greatest height; 

the greatest width is in the posterior quarter of the greatest 

length. The ends are rounded, the posterior margin meets 

the convex ventral margin slightly higher than it does the 

anterior margin. The sulcus is deep, concave towards the 

anterior, located in the front part of the central one-third of 

the greatest length. The adductor muscle-attachment scar 

consists of a vertical row of five scars concave towards the 

anterior and is located on the anterior wall of the sulcus. The 

dorsoanterior part of the sulcus curves forward above the 

central horizontal rib to outline a low rounded node on the 

interior of the valve (pl. 2, figs. 21, 23-25; pl. 7, fig. 24). 

The lower two horizontal ribs are joined at the ends to form 

an ellipse, the lower rib is located just below the bottom of 

the sulcus, and the middle rib crosses the sulcus (pl. 7, figs. 

17, 19). 

Measurements (in mm) (unfigd. = unfigured specimen).-

Greatest Greatest 

length height 

Paratype. USNM 389827, unfigd. 0.55 0.30 

Paratype, USNM 389826, unfigd. .61 .27 

USNM 389822 .61 .32 

USNM 389817 .64 .32 

Paratype, USNM 389825, unfigd. .65 .32 

USNM 389823 .72 .32 

USNM 389824 .80 .32 

Discussion.-The diagnosis and description are based on 

seven poorly preserved specimens. Dimorphism appears to 

be reflected by the greater width near the posterior of the 

largest available specimen (pl. 7, figs. 23-25) presumed to 

be a female. Although a steinkern, this specimen is desig-
nated as the holotype. A poorly preserved steinkern (USNM 

389940) also may belong to this species. 

Geologic range.- Middle and Upper Triassic, Ladinian 

to Norian, from 36.4 to 144.5 m (120-447 ft) above the 

base of the Shublik Formation. 

Covracythere binoda Sohn, n. sp. 

Plate 7, figures 1-3 

Etymology of name.-Two small nodes in front of sulcus 

on each silde of the second rib. 

Holotype.-Left valve, USNM 389818. 

Type level.-Ladinian, from 36.4 to 37.9 m above the 

base of Shublik Formation. 

Type locality.-Fire Creek section, Mount Michelson 

quadrangle, Alaska. USGS Mesozoic colin. 33111. 

Diagnosis.-Covracythere with four horizontal ribs, 

elongated posterior-trending sulcus below first to above 

third rib, and two small nodes in front of sulcus on each side 

of second rib. 

Description.-The valve is subquadrate, the dorsal and 

ventral margins are straight, the anterior margin is evenly 

rounded, the anterior is probably straight in the dorsal twothirds and probably truncated towards the venter. The dorsal 

rib is connected to the second rib, subparallel and slightly 

removed from the anterior margin, the second rib is connected to the third rib near the posterior margin, and the 

fourth rib is convex ventrad and connected to the anterior of 

the third rib. A straight sulcus extends backward from below 

the first rib to above the third rib. Two small rounded nodes 

are located on each side of the third rib in front of the sulcus. 

The second rib is broken by the sulcus. 

Discussion.- Although only a single left valve is available, it is formally described because it differs from the 

known taxa in the genus by having two nodes. 

Measurements (in mm).-USNM 389818, greatest 

length 0. 50, greatest height 0. 30. 

Geologic range.- Known only from the Ladinian part of 

the Shublik Formation, from 36.4 to 37.9 m (120-125 ft) 

above the base of the Shublik Formation. 

Genus DETTERMANIA n. gen. 

Type species.-D. truncata n. sp. 

Etymology of name.-In honor of my colleague R. L. 

Detterman, U.S. Geological Survey, who collected the samples. 

Diagnosis.-Small, greatest length less than 1 mm. 

Straightbacked; sulcate, with anterocentral node anterior to 

sulcus. Smooth or finely punctate; with two or more horizontal ribs; dorsum flat, dorsal margin straight, ventral margin convex, rounded anterior margin and pointed posterior 

margin. Left over right overlap slight, dimorphic in width of 

posterior. Hingement and adductor muscle scar unknown. 

Discussion.- This genus differs from Covracythere 

Gramm, 1975, described from the Upper Anisian in the 

Soviet Far East and present also in Alaska, in lateral outline 

and in having a subcentral node in front of the sulcus. 

Species assigned.-D. truncata n. sp. and 

?Monoceratina subtriangulata Huang and Gou, 1977 (Ye 

and others, 1977) from the Norian of Yunnan, The People's 

Republic of China (P.R.C.). 

Geologic range.-Middle and Upper Triassic. 

Geographic distribution.- Known from Yunnan, 

P.R.C., and northeastern Alaska. 

Dettermania truncata Sohn, n. sp. 

Plate 7, figures 4-15 

New genus, n. sp. Sohn, 1984b, p. 21, fig. III. 

Etymology of name.-Truncated posterior. 

Holotype.-Heteromorph, USNM 389820. 

Paratypes.- USNM 389819, 389821. 

Type level.-Ladinian, from 37.9 to 39.4 m above base 

of Shublik Formation. 

Type locality.-Fire Creek section, Mount Michelson 

quadrangle. USGS Mesozoic colln. 33112. 

Diagnosis.-Dettermania with four ribs, second rib from 

top weakly developed; straight dorsal margin, convex ventral margin curving sharply backwards to form acute posterior margin, anterior margin evenly rounded. Sulcus wide, 

shallow, posterior to low rounded node extending from the 

third, strongest rib to level of weak second rib; fourth rib 

weaker than first. Dimorphic in width of posterior. 

Description.-The shell is relatively thick as illustrated 

in plate 7, figure 4. The hinge margin is straight, the dorsum 

is flat, bounded by the straight dorsal rib. The ventral margin is convex, curves roundly into the anterior margin, and 

bends backward and upwards below the approximate posterior end of the third, strongest rib. A shallow, wide sulcus 

extends from below the dorsal rib to the third, best developed rib. This sulcus curves towards the anterior to delineate 

a subround node that extends upwards to the elevation of the 

very faint second rib (pl. 7, figs. 9-11). 

Measurements (in mm).-USNM 389820, greatest 

length 0.43+, greatest height 0.5+; USNM 389819, greatest length 0.75+, greatest height 0.39+; USNM 389821, 

greatest length 0.98, greatest height 0.42. 

Discussion.-This species is dimorphic in width of posterior. Plate 7, figure 9, illustrates the heteromorph which has 

a relatively wider posterior than the tecnomorph that is 

shown on plate 7, figure 14. 

In lateral outline the species resembles Monoceratina 

subtriangulata Huang and Gou, 1977 (Ye and others, 1977, 

p. 282, pl. 1, fig. 21), from the Upper Triassic Shizhongshan Formation of Jinchuan, Yunnan, P.R.C. Although that 

species was described as having only one ventral rib, the 

original illustration shows also a dorsal rib and a deep subcentral sulcus; consequently, M. subtriangulata is questionably referred to Dettermania. 

Geologic range.-Known only from the Ladinian, from 

37.9 to 39.4 m (125-130 ft) above the base of the Shublik 

Formation. 

Middle And Upper Triassic Marine Ostracoda, Northeastern Alaska C11 
Family unknown 

Anderson (1964, p. 138) questionably classified the 

genus Rhombocythere in the Brachycytheridae Puri, 1954. 

Based on the species assigned to the genus, the genus probably does not belong in the Brachycytheridae. 

Genus RHOMBOCYTHERE Anderson, 1964 

Rhombocythere Anderson, 1964, p. 138. 

Notocythere Will, 1969, p. 60. 

Type species.-Rhombocythere wicheri Anderson, 1964, 

p. 138, pl. 9, figs. 1-8. Lower Rhaetian, borehole, Germany. 

Original diagnosis.-'' Medium sized oblong-ovate carapace, smooth or with close small circular puncta set in wide 

shallow depressions. Normal pore canals open into the 

punctae frequently in pairs. Anterior and posterior margins 

flanged. Dorsal and ventral margins carinate. Venter flattened. Hinge straight, long and sunk. Dentition of Hemicythere type. In the left valve a crenulate bar terminates 

anteriorly in a small undivided tooth in front in which is a 

deep socket. A similar socket occupies the postero-dorsal 

angle. In the right valve a shallow socketted groove is succeeded anteriorly and posteriorly by large anvil-shaped 

teeth. Lamella free and wide, radial pore canals straight and 

widely spaced. General shape like Camptocythere. Left 

valve larger.'' 

Discussion.-In addition to the type species, Anderson 

(1964) described and illustrated R. ruegeri and R. schotti. 

He based the holotypes of the three species on specimens 

originally illustrated in open nomenclature by Wieber 

(1951) from Lower Rhaetian cores in boreholes, Germany. 

In addition, Anderson (1964) described and illustrated R. 

penarthensis from the Lower Rhaetian of South Wales. 

The following Upper Triassic taxa have been described 

in, or referred to, Rhombocythere: 

Notocythere elegans Will, 1969, p. 73, pl. 3, figs. 1, 2. 

Rhaetian. 

Gemmanella (Rhombocythere) gracilis Kozur, 1968a, 

p. 851, pl. 2, figs. 1, 2, text figs. 2, 3 = R. gracilis 

(Kozur, 1968) fide Kozur, 1972a, p. 642. Lower 

Rhaetian. 

Notocythere hechti brevis Will, 1969, p. 72, pl. 2, figs. 

6a-d. Upper Norian. 

N. hechti hechti Will, 1969, p. 68, pl. 2, figs. 3a, b, text 

figs. 25-28. Upper Norian. 

N. hechti longa Will, 1969, p. 71, pl. 2, figs. 5a-d. Upper 

Norian. 

N. hechti nodosa Will, 1969, p. 70, pl. 2, figs. 4a, b. Upper 

Norian = junior secondary homonym of Rhombocythere 

nodosa (Kozur, 1968a). 

Notocythere magna intermedia Will, 1969, p. 79, pl. 3, 

figs. 4a, b. Rhaetian. 

N. magna magna Will, 1969, p. 75, pl. 3, figs. 2a, b, text 

figs. 29-31 = R. wicheri Anderson, 1964. Rhaetian. 

C12 Shorter Contributions to Paleontology and Stratigraphy 

N. magna maritima Will, 1969, p. 77, pl. 3, figs. 3a-d. 

Rhaetian= R. schotti Anderson, 1964. 

N. media excelsa Will, 1969, p. 66, pl. 2, figs. 2a, d. 

Rhaetian. Not conspecific with Notocythere media excelsa Will in Dadlez and Kopik, 1963, p. 139, pl. 1, fig. 

10. 

N. media media Will, 1969, p. 65, pl. 1, figs. 6a-d. Norian 

(type species of N otocythere). 

N. media prima Will, 1969, p. 63, pl. 1, figs. 7a-d. Upper 

Norian. 

Gemmanella (Rhombocythere) nodosa Kozur, 1968a, 

p. 852, pl. 1, figs. 14, 15 = R. nodosa Kozur, 1968, fide 

Styk, 1982, p. 21. Lower Rhaetian. 

Notocythere obliqua Will, 1969, p. 79, pl. 1, figs. 5a, b. 

Rhaetian. 

Rhombocythere penarthensis Anderson, 1964, p. 140, pl. 

10, figs. 18-25. Rhaetian. 

R. ruegeri Anderson, 1964, p. 139, pl. 9, figs. 9-12. 

Rhaetian. 

R. schotti Anderson, 1964, p. 139, pl. 11, figs. 13-15. 

Rhaetian. 

Gemmanella willi willi Dreyer, 1967, p. 506, pl. 7, 

figs. la-d = R. penarthensis Anderson, 1964. Rhaetian. 

G. willi laevis Dreyer, 1965, p. 507, pl. 7, figs. 2, 3, 

4a-d = R. wicheri Anderson, 1964. Rhaetian. 

Rhombocythere wicheri Anderson, 1964, p. 138, pl. 9, 

figs. 1-8. Rhaetian. 

The Lower Rhaetian species Rhombocythere gorvoziensis 

Styk, 1972 (p. 876, 884, pl. 3, figs. 6-8) does not belong 

in the genus. Styk (1982, p. 22, pl. 3, figs. 1, 2) placed her 

species in subjective synonymy with Speluncella tenuistriata Kozur, 1968a, in the new combination R. tenuistriata 

(Kozur, 1968a). Based on their lateral outlines and surface 

morphology, the two are not conspecific, and neither belongs in Rhombocythere. 

The two inadequately preserved specimens from the Ladinian of Alaska are questionably referred to Rhombocythere solely on external morphology. 

Geologic range.-Ladinian?, Norian, and Rhaetian. 

Geographic distribution.-Known only from Europe, 

and ?northeastern Alaska. 

Rhombocythere? sp. 

Plate 10, figures 10, 11 ; plate 11 , figures 28-31 

Discussion.-A fragment of a left valve with the dorsal 

and end margins missing, and a poorly preserved steinkern 

of a right valve on matrix resemble Rhombocythere . Features in common with the genus are as follows: Straightbacked in lateral outline; carinate anterior and ventral margins (the posterior and dorsal margins are not preserved), 

anterior margin wider than posterior in lateral outline, in 

dorsal outline wider towards anterior; and puncta similar to 

R. penarthensis Anderson, 1964 (Anderson, 1964, pl. 10, 

figs. 18, 19; Bate, 1978, pl. 1, fig. 10) preserved near the 
posterior margin (pl. 11, fig. 30). Because the dorsal and 

end margins are missing and the adductor muscleattachment scar is not preserved on the fragment, the internal morphology diagnostic of Rhombocythere is unknown 

for the specimens on hand. 

The fragment of a left valve illustrated on plate 10, figure 

11, was tilted in the SEM (to look for a possible adductor 

muscle-attachment scar) so that the dorsal edge was below 

the plane of the micrograph. The tilting resulted in the 

distortion of the ventral groove for reception of the smaller 

valve. Examination with reflected light at X160 shows the 

proximal boundary of the groove is at the edge of the valve 

surface as shown by arrows. I cannot interpret the thin ridge 

that is terminated by minute toothlets inside the groove. 

Anderson (1964, pl. 10, figs. 21-23) showed that the left 

valve overlaps the right along the free margins, and Will 

(1969, p. 69, text figs. 25, 26) illustrated widely spaced 

radial pore canals along the ventral margin of Notocythere 

( = Rhombocythere ) . The thin ridge inside the groove along 

the ventral margin shown on figure 11 may represent infilling of the vestibule. The minute toothlets on either side of 

the ridge could possibly represent bases of radial pore 

canals; however, the entire structure may be an artifact 

resulting from fossilization. 

The specimens on hand differ from all the known species 

in Rhombocythere in having a shallow kidney-shaped trough 

on the central part of the lateral surface; a shallow indentation from above into the dorsal boundary of the trough (pl. 

10, fig. I 0; pl. 11 , figs. 29, 30); and widest in front of 

midlength in dorsal outline. 

Measurements (in mm).-USNM 389853, greatest 

length 0.50, greatest height 0.40; USNM 389912, greatest 

length 0.62, greatest height 0.33. 

Geologic range.-Ladinian, from 65.3 to 67.1 m (215-

220 ft) above the base of the Shublik Formation. 

Suborder METACOPINA Sylvester-Bradley, 

in Moore, 1961 

Superfamily HEALDIACEA Harlton, 1933 

Sohn ( 1965) discussed this superfamily. The aggregate 

adductor muscle-attachment scar also is present in nonmarine podocopids of Mississippian age (Sohn, 1985). This 

similarity indicates homeomorphy rather than phylogeny in 

the evolution of the so-called healdiid adductor muscle scar. 

lFamily HEALDIIDAE Harlton, 1933 

Gramm (1982, p. I94-198) published the best and most 

recent discussion of the family and the genus Healdia with 

superb SEM micrographs of the adductor muscleattachment scars of genera in the family. 

Genus HEALDIA Roundy, 1926 

Type species (original designation).-H. simplex 

Roundy, 1926, p. 8, pl. I, fig. lla-c. Graham Formation 

(Upper Pennsylvanian), Stephens County, Texas. 

Discussion.-Shaver (Moore, 1961, p. Q361) recorded 

the stratigraphic range of Healdia to be Devonian to Permian, but Coryell (1963, p. 929) listed three Lower Jurassic 

species of Healdia. Sohn (1968, p. 52) recorded two taxa in 

the Triassic: Healdia bella Gerke, 1937, from the Lower 

Triassic of Siberia, as a nomen nudum, and Ostracode C 

Kristan-Tollmann, 1964, as Healdia? sp. However, 

Kristan-Tollmann (1971a, p.51) described the new genus 

Torohealdia and designated Ostracode C as the type 

species, T. amphicrassa n. gen. n. sp., from the NorianRhaetian of the Alpine Triassic. 

The following species from the Triassic have been described in or referred to H ealdia : 

Will (1969, p. 52) described from the Rhaetian of northwestern Germany Healdia? tenuivirgata = Ogmoconcha 

martini (Anderson, 1964) fide Bate, 1978, p. 82. Gramm 

( I969a) illustrated the adductor muscle scars in open 

nomenclature of Healdia sp. 1, H.? sp. 2, andH. sp. 3, and 

the carapaces of H. sp. I and H.? sp. 2 from the Upper 

Anisian of the Primor'ye Region, U.S.S.R. The next year, 

Gramm ( 1970) described the specimens and erected H ealdia 

unitumulata and also H. zharnikovae to which he referred 

H. sp. 1 Gramm, 1969, and H. spp. 3 to 8 Gramm, 1969a. 

Kozur (1970a, p. 21-23) described from the Upper Anisian 

of Hungary Healdia (Healdia) anisica, H. (H.) felsooerensis, and H. (Hungarella) reniformis (Mehes, 1911) and 

stated that the three species have a nondenticulated hinge. 

Bolz (197lb, p. 742, 744, pls. 3, 4) illustrated Healdia spp. 

A to G from the Alpine Norian-Rhaetian. Kozur (1972a, 

table 1) listed from the Rhaetian of Germany Healdia 

(Hungarella) as pinata Drexler, 1958, originally described 

from the Lower Jurassic, H. (Hungarella) caudata Anderson, 1964, H. (Hungarella) martini Anderson, 1964, and 

H. (Hungarella) owthropensis Anderson, 1964. Urlichs 

1972 (1973 fide Kristan-Tollmann and Hamedani, 1973, 

p. 210), p. 688, identified Healdia martini (Anderson, 

1964) from the German Upper Norian-Rhaetian. Urlichs' 

illustrated specimens, however, do not have a posterolateral 

hump on the left valve; consequently, they are not conspecific with Anderson's species. Gheorgian (1976, p. 37) 

identified and illustrated Healdia (Healdia) felsooerensis 

Kozur, 1970, from the Ladinian of Rumania. The presence 

of two spines on each valve of the Rumanian specimen 

excludes that species from H ealdia (H. ) felsooerensis. Hou 

and Gou, 1977 (Y e and others, 1977, p. 301), described and 

illustrated Healdia jingguensis from the Carnian of Yunnan, 

P.R.C. 

Because Gramm (1969a, p. 457, figs. 1, 2; 1970, p. 45, 

figs. 1 , 2) illustrated the adductor muscle-attachment scars 

of H ealdia zharnikovae with a few scars, similar to those 

illustrated herein, I am referring the specimens from Alaska 

to "Healdia." The Triassic species lack the dorsoposterior 

flattening originally described in Healdia. The discovery of 

Middle And Upper Triassic Marine Ostracoda, Northeastern Alaska C13 
better preserved Triassic specimens may require the establishment of a new genus. 

These specimens are not formally named because only 

one carapace with part of the right valve and the posterior 

dorsal portion of the left valve retained is available; the 

others are steinkerns. Plate 1, figures 1-4, are of a steinkern 

with the same lateral outline as the other illustrated specimens. Although the posterior lateral ridge is not preserved, 

this specimen is included because the denticulate hinge is 

partly preserved on the posterior and dorsal views (pl. 1, 

figs. 1 , 3). Plate 1 , figures 5-9, are of a smaller steinkern 

that has a well preserved adductor muscle scar as well as 

dorsal attachment muscle scars (pl. 1, figs. 6-8) and a faint 

indication of a denticulate hinge (pl. 1, fig. 5). 

Plate 1, figures 10-14, are of the largest available 

steinkerns that show straight posterior lateral ridges instead 

of curved ridges as on the illustrated specimens that follow. 

Plate 1, figure 13, has a poorly preserved adductor muscleattachment scar that is similar in number of individual spots 

(stigmata) to that illustrated on figures 7, 8, and 18. These 

scars resemble the pattern illustrated by Gramm ( 1969a, 

p. 457, fig. 1.1-1.5) for Healdia sp. 1 (=H. zharnikovae 

Gramm, 1970) from the upper Anisian, and the posterior 

ridge on H. sp. 3 Gramm [1969a, figs. 4g, d (4d, e in 

English translation)] resembles the specimen illustrated 

herein as figures 12 and 13. 

Prof. M. N. Gramm kindly examined the illustrations and 

a preliminary version of this discussion. He stated (written 

commun., July 12, 1984) that the adductor muscleattachment scar pattern on the specimens from Alaska are 

close to those he had illustrated on specimens from the 

Primor'ye Region. He added that he had seen denticulation 

along the hinge of the right valve of Healdia sp. 3 (Gramm, 

1970, pl. 7, fig. 2). Plate 1 , figures 15-21 , show the adductor muscle-attachment scar pattern and denticulate hinge, 

but, because the posterior lateral ridges are curved on this 

specimen and appear to be straight on the steinkern illustrated on plate 1, figures 12 and 13, this specimen probably 

represents a different species. The specimens are illustrated 

herein as "Healdia" sp. 1, sp. 2, and sp. 3. 

Geologic range.-Devonian-Triassic, ?Lower Jurassic. 

Geographic distribution.-Cosmopolitan. 

"Healdia" sp. 1 

Plate 1 , figures 1-9 

Discussion.-Two steinkerns and one measured specimen (USNM 389808) on which the right valve is missing 

and the anterior part of the left valve is missing are illustrated herein. The cast of the right valve on this specimen 

has a well-preserved adductor muscle-attachment scar that is 

similar to those illustrated herein (pl. 1, figs. 7, 8, 10), and 

the posterior of the left valve does not have a posterolateral 

ridge nor is one preserved on the cast of the right valve. 

Measurements (in mm).-USNM 389804, greatest 

length 0.48, greatest height 0.30; measured specimen 

C14 Shorter Contributions to Paleontology and Stratigraphy 

USNM 389808, greatest length 0.50, greatest height 0.28; 

USNM 389803, greatest length 0.53, greatest height 0.30. 

Geologic range.-Ladinian, limestone and dolomite 

member, from 36.6 to 66.5 m (120-215 ft) above the base 

of the Shublik Formation. 

"Healdia" sp. 2 

Plate 1 , figures 10-14 

Discussion.-One steinkern with straight posterolateral 

ridges that differ from the curved ridges of "Healdia" sp. 3 

is illustrated. The adductor muscle-attachment scar is poorly 

preserved (fig. 13) but is within the limits of those illustrated 

herein for "Healdia". 

Measurements (in mm).-USNM 389805, greatest 

length 0.60, greatest height 0.40. 

Geologic range.-Ladinian, limestone and dolomite 

member, from 65.5 to 70.1 m (215-220 ft) above the base 

of the Shublik Formation. 

"Healdia" sp. 3 

Plate 1 , figures 15-21 

Discussion.-In addition to the illustrated specimen, a 

steinkern (USNM 389807) from the Ladinian has an adductor muscle scar with four rows of stigmata arranged in a 

more circular outline than those illustrated. In addition, two 

specimens from the Carnian (USGS colin. 33143), one of 

which is a carapace and the other the posterior half of a 

carapace (USNM 389809), have curved posterolateral 

ridges. These specimens are probably conspecific with the 

one illustrated herein. 

Measurements (in mm).-Unfigured specimen, USNM 

389807, greatest length 0.42, greatest height, 0.28; USNM 

809806, greatest length 0.53, greatest height 0.35; two unfigured specimens, USNM 389809, broken carapace greatest length 0. 35, greatest height 0. 31, carapace, greatest 

length 0.50, greatest height 0.32. 

Geologic range.-Ladinian, limestone and dolomite 

member, from 35. 1 to 36.6 m (115-120 ft) above the base 

of the Shublik Formation, and Carnian, Limestone Member, 

from 97.5 to 99.1 m (320-325 ft) above the base of the 

Shublik Formation. 

Genus PSEUDOBYTHOCYPRIS Shaver, 1958 

Type species.-Bythocypris pediformis Knight, 1928 

Discussion.-Sohn (1983, p. 27) discussed this genus 

and recorded the geologic range of Pseudobythocypris to be 

Mississippian through Permian, but, based on this possible 

Triassic occurrence, the range is here questionably extended 

into the Upper Triassic (Carnian). 

Psuedobythocypris? sp. 

Plate 2, figures 14-17 

Discussion.-The unique specimen is a thin-shelled, 

smooth carapace with a gently curved dorsal margin, a 

rounded anterior margin, and a truncated posterior margin. 
The dorsal outline is elliptical, with gently curved sides and 

relatively blunt, equal ends. The greatest width is in front of 

the midlength. The carapace resembles the Pennsylvanian 

Bythocypris pediformis Knight, 1928, the type-species of 

Pseudobythocypris. Bolz (1971a, p. 235, pl. 8, figs. 120-

121) illustrated from the Norian-Rhaetian, Norten Alps, the 

right views of one in star and one adult of Bythocypris sp. B 

that differ from the specimen on hand in being slightly 

higher and larger (length 0. 80-0.91 mm, height 0.41-0. 50 

mm, and width 0.38-0.43 mm). Bate (1978, p. 180, pl. 1, 

fig. 4) illustrated the left view of a carapace of Lower 

Anisian age as Bythocypris sp. B Bolz, 1971. The specimen 

from Britian has the right valve larger than the left instead 

of the reverse as in both Bythocypris and Pseudobythocypris 

and should not be considered congeneric with the specimens 

discussed above. Because the adductor muscle-attachment 

scar of the carapace from Alaska is unknown, it is only 

tentatively referred to the Paleozoic genus. 

Measurements (in mm).-USNM 389813, greatest 

length 0.70, greatest height 0.35, greatest width 0.26. 

Geologic range. -Known only from the Carnian, limestone member, 94.5 to 96.0 m (310-315 ft) above the base 

of the Shublik Formation. 

Genus OGMOCONCHA Triebel, 1941 

Ogmoconcha Triebel, 1941, p. 377; Sohn, 1968, p. 29; 

Malz, 1971, p. 434; Lord, 1972, p. 332; 1982, p. 262; 

Kristan-Tollmann, 1977, p. 133, 142. 

Hungarella Mehes, 1911 sensu Anderson, 1964. 

Type species.-0. contractu/a Triebel, 1941, p. 377, pl. 

14, figs. 156-160. Liassic, borehole, Germany. 

Diagnosis (from Anderson, 1964, p. 146).-"A smooth 

genus in the Healdiidae with strong overlap of the left valve 

over right on all margins. Hinge margin of right valve with 

minute vettically oriented teeth which articulate with serial 

sockets in left valve. Adductor muscle-attachment scar aggregate." 

Description.- According to Triebel (1941, p. 378), Ogmoconcha is small to medium sized, with thick, smooth 

shells. The carapace is elliptical to egg -shaped in lateral, 

dorsal, and end views. The left valve has a marginal groove 

for the reception of the right valve. Abundant minute, normal pore canals are simple; marginal pore canals are barely 

discernable, and a definite zone of concrescence (Verschmeltzungszone) is not discernible. 

Discussion.-As indicated in the discussion of the Hungarella-Ogmoconcha problem, most of the Triassic species 

have been recorded as Hungarella Mehes, 1911. Lord 

(1972, p. 323) listed the Triassic species under Hungarella 

and the Liassic species under Ogmoconcha. Following is an 

objective list of Triassic species that have been described in, 

or transferred to, Ogmoconcha: 

Torohealdia amphicrassa Kristan-Tollmann, 1971a, by 

Urlichs,. 1972, p. 691. Upper Norian. 

Hungarella bristolensis Anderson, 1964, by Bate, 1978, p. 

182. Upper Rhaetian, Liassic. 

H. caudata Anderson, 1964, by Bate, 1978, p. 182. Lower 

Rhaetian. 

Ogmoconcha hqgenowi Drexler, 1958, by Urlichs, 1972, p. 

690. Upper Norian. 

0.? limbata (Reuss, 1868) sensu Urlichs, 1971, herein. 

Ladinian. 

Hungarella martini Anderson, 1964, by Bate, 1978, p. 182. 

Upper Rhaetian. 

H. moorei (Jones, 1894) Anderson, 1964, by Bate, 1978, 

p. 182. Upper Rhaetian. 

H. owthropensis Anderson, 1964, by Bate, 1978, p. 180. 

Lower Rhaetian. 

Ogmoconcha sp. Urlichs, 1972, p. 693. Norian-Rhaetian. 

Because several Triassic ostracodes in Alaska have an 

aggregate adductor muscle-attachment scar and some of 

these have denticulate hinges, the genus Ogmoconcha is 

confirmed in the Triassic. Many, but not all, of the Triassic 

species referred to Hungarella Mehes, 1911, that have a 

denticulate hinge probably belong in Ogmoconcha. 

Key to the species of Ogmoconcha in Alaska 

1. Posteroventral spine on right valve .... unicerata 

1a. No posteroventral spine on right valve . . . . . . . 2 

2(1 a). Height over length index less than 

0. 700 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . tailleuri 

2a. Height over length index 0. 700 or more ....... 3 

3(2a). Horizontal pleat below dorsal margin of left 

valve ........................... aff. limbata 

3a. No horizontal pleat below dorsal margin of left 

valve ................................... 4 

4(3a). Anterior margin of left valve higher than 

posterior . . . . . . . . . . . . . . . . . . . . . . . . marquardti 

4a. Anterior margin of left valve not higher than 

posterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 

5(4a). Posterior margin in dorsal outline 

obtuse . . . . . . . . . . . . . . . . . . . . . aff. owthropensis 

5a. Posterior margin in dorsal outline 

acute . . . . . . . . . . . . . . . . . . . . . . . . . . . alaskaense 

Geologic range.-Triassic-Jurassic. 

Geographic distribution.- Europe, Asia, and 

northeastern Alaska. 

Ogmoconcha sp. aff. 0. owthropensis (Anderson, 1964) 

Plate 5, figures 11-16; plate 6, figures 1-9; plate 8, 

figures 7-9, 20-27; plate 9, figures 9-16, 19-23. 

Hungarella owthropensis Anderson, 1964, p. 147, pl. 14, 

figs. 96-101. Lower Rhaetian, Nottinghamshire, Great 

Britian. 

Ogmoconcha owthropensis (Anderson, 1964) Bate, 1978, 

p. 180, pl. 1 , figs. 11, 15. Same specimens as above. 

Gen. and sp. indet. ex gr. Ogmoconcha Triebel, 1941. 

Sohn, 1984b, p. 21, fig. llK. 

Discussion.-The holotype, a carapace, was recorded by 

Anderson (1964, p. 147) to be 0.625 mm long and 0.450 

mm high. The height over the length (h/1) index of the 

Middle And Upper Triassic Marine Ostracoda, Northeastern Alaska C15 
holotype equals 0. 720. Specimens from Alaska range in 

length from 0.41 to 0.61 mm and in height from 0.29 to 0.43 

mm, and their h/1 ranges from 0. 700 to 0.800. In addition 

to size and h/1 index, these specimens have in common with 

0. owthropensis a relatively straight ventral contact, a relatively blunt posterior outline in dorsal view with evenly 

curved sides that taper more towards the anterior than towards the posterior, and a similar outline in end view~ The 

hinge of a paratype of 0. owthropensis is denticulated and 

tripartite with a narrow central portion and wider end portions (Anderson, 1964, pl. 14, fig. 101; Bate, 1978, pl. 1, 

fig. 15). The specimens in Alaska have poorly preserved 

denticulate hingements. The posterior two-thirds of the right 

valve of the carapace illustrated on plate 5, figures 11-16, 

is missing, thus exposing denticulations only along the center of the hinge, and the left valve illustrated on plate 9, 

figures 9-12, has a denticulated hinge that may not be 

tripartite. Twelve specimens from Ladinian to Norian collections in Alaska are illustrated to show that they can vary. 

Better preserved material may disclose that more than one 

species may be represented. 

Measurements (in mm).-

USNM 389860 

USNM 389919 

USNM 389881 

USNM 389880 

USNM 389857 

USNM 389884 

USNM 389861 

USNM 389886 

USNM 389852 

USNM 389879 

USNM 389877 

USNM 389878 

Greatest 

length 

0.41 

.41 

.41 

.44 

.45 

.50 

.50 

.50 

.51 

.52 

.56 

.61 

Greatest 

height 

0.29 

.30 

.31 

.32 

.32 

.36 

.40 

.40 

.39 

.40 

.40 

.43 

Height! 

length 

0.707 

.732 

.756 

.727 

.711 

.720 

.800 

.800 

.765 

.769 

.714 

.705 

Geologic range.-Ladinian through Norian, from 33.5 to 

145.4 m (11 0-4 77 ft) above the base of the Shublik Formation. 

Ogmoconcha alaskaense n. sp. 

Plate 5, figures 23-28; plate 9, figures 17, 18, 24, 25; 

plate 11, figures 17-19 

Gen. and sp. undet. ex gr. Ogmoconcha Triebel, 1941. 

Sohn, 1984b, p. 21, fig. 1F. Herein pl. 11, figs. 17-19. 

Etymology of name.-Type locality in Alaska. 

Holotype~-USNM 389887. 

Paratypes.-USNM 389859, 389870, 389885, 389894, 

389896, 389935, 389937, 389938, 389950, 389951. 

Type locality.-Fire Creek reference section of Shublik 

Formation. USGS colln. 33149. 

C16 Shorter Contributions to Paleontology and Stratigraphy 

Type level.- Norian, clay shale member of Shublik Formation. 

Diagnosis.-A species of Ogmoconcha with a height to 

length index of more than 0. 700 and with an acute posterior 

outline in dorsal view. 

Description.- The carapace is smooth, without any 

spines or pleats. In lateral outline, the dorsal margin is 

convex with the greatest height behind midlength, the ventral margin is straight, and the anterior margin is narrower 

than the posterior margin. The dorsal margin is elliptical, 

with the greatest width behind midlength, and the anterior 

end is slightly more acute than the posterior end. The hingement is denticulate. 

Measurements (in mm) (figd. =figured specimen).-

USNM 389870 

USNM 389951 

USNM 389938 

USNM 389935 

USNM 389885, figd. 

USNM 389950 

USNM 389859, figd. 

USNM 389896, figd. 

USNM 389887, figd. 

USNM 389894 

USNM 389937 

Greatest 

length 

0.40 

.40 

.41 

.42 

.42 

.42 

.43 

.46 

.51 

.55 

.55 

Greatest 

height 

0.30 

.30 

.30 

.30 

.31 

.31 

.31 

.34 

.40 

.40 

.42 

Height! 

length 

0.750 

.750 

.732 

.714 

.738 

.738 

.721 

.739 

.784 

.727 

.763 

Discussion.- Specimens with the height to length index 

of more than 0. 700 differ from the specimens illustrated 

herein as 0. sp. aff. 0. owthropensis (Anderson, 1964) in 

that they have a more acute posterior in dorsal outline. 

These specimens are not considered to be sexual dimorphs 

of the above taxon because they range in length from 0.40 

to 0.55 mm, thus representing two or more growth stages 

younger than 0. sp. aff. 0. owthropensis of which the 

largest specimen is 0.61 mm in length. The hingement of a 

juvenile is denticulate (pl. 5, figs. 25, 28), but the adductor 

muscle scar of the new species is unknown. The holotype 

(pl. 9, figs. 24, 25) lacks part of the posterior of the right 

valve, but the outline of the posterior end of the left valve 

in dorsal view is definitely acute. 

Geologic range.-Norian, clay shale member, from 

112.8 to 143.3 m (370-470 ft) above the base of the Shublik 

Formation. 

Ogmoconcha unicerata Sohn, n. sp. 

Plate 5, figures 1-10 

Ogmoconcha n. sp. Sohn, 1984b, fig. 11A-D. 

Etymology of name.-Posteroventral spine on right valve 

only. 

Holotype.- USMN 389855. 
Paratype.- USNM 389856. 

Type level.-Ladinian. USGS colln. 33112. 

Diagnosis.-Ogmoconcha with a posteroventral spine on 

the smaller right valve. 

Description.-The carapace is small, less than 0.5 mm in 

greatest length, the valves are subovate, the ends are 

rounded, the dorsoanterior margin is more gently rounded 

than the dorsoposterior margin, and the overlap is even 

around all the margins. A stout spine, of which only the base 

is preserved on the specimens recovered, is located about 

equidistant from the ventral and posterior margins on the 

right valve. The greatest length is approximately at midheight, the greatest height is slightly behind midlength. The 

dorsal outline is subelliptical, the anterior end is narrower 

than the posterior end, and the greatest width is behind 

midlength. 

Measurements (in mm).-USNM 389855, greatest 

length 0.42, greatest height 0.30, h/1 0. 714; USNM 389856, 

greatest length 0.43, greatest height 0.29, h/1 0.674. 

Discussion.-Healdia (Hungarella) reniformis (Mehes, 

1911) of Kozur, 1970, as illustrated by Kozur (1970b, 

p. 22, pl. 4, figs. 15-17) from the Anisian and Ladinian 

near Felsoc)rs, Bakony, Hungary, also has a ventroposterior 

spine on the right valve. The specimens from Alaska differ 

from Hungarian specimens not only in a more elongate 

lateral outline and in lacking a ridge below the posterior half 

of the dorsal margin of the right valve (pl. 10, figs. 12, 13) 

but also in the fact that the hingement of the Hungarian 

specimens is smooth ("Schlosselemente glatt"), whereas the 

specimens from Alaska have a denticulated hinge as shown 

herein (pl. 5, figs. 1, 2). The largest specimen from Felsoors 

recorded by Kozur (1970b) is 0.520 mm long. Mehes (1911, 

p. 22), however, recorded the length of his Bairdia(?) 

problematica var. reniformis as 0. 71 mm. Specimens as 

long as 0. 70 mm with a ventroposterior spine on the right 

valve and a denticulate hinge are present in the Lower Carnian marl from Csopak, Nesztery Valley, Hungary (Sohn, 

1984b, figs. 11E-G; herein pl. 10, figs. 12-14). In addition, specimens in the same collection without a posteroventral spine on the right valve that have denticulate hinges 

(pl. 11 , figs. 13-16, 20-24) are present in the Hungarian 

Triassic. Unfortunately, I have not been able to determine 

the adductor muscle scar in my specimens from Hungary, 

even after converting some specimens to fluorite. 

Geologic range.-Ladinian, limestone and dolomite 

member, from 38.1 to 39.6 m (125-130 ft) above the base 

of the Shublik Formation. 

Ogmoconcha tailleuri n. sp. 

Plate 5, figures 17-22; plate 6, figures 10-18; 

plate 8, figures 1-6, 10-19; plate 9, figures 1-4; 

plate 10, figures 1-8, 15-22; plate 11, figures 7-12. 

?Ogmoconcha sp. Urlichs, 1972, p. 693, 

pl. 4, fig. 6. Norian, Austrian Alps. 

Etymology of name .-In honor of my colleague I. L. 

Tailleur, U.S. Geological Survey. 

Holotype .-USNM 389865. 

Paratypes .-USNM 389858, 389862-389864, 389866-

389869, 389875, 389876, 389883, 389888, 389899, 

389901-389904, 389907' 389908, 389910, 389911' 

389914-389917, 389926. 

Type leve/.-Ladinian, limestone and dolomite member, 

from 48.8 to 50.3 m (160-165 ft) above the base of the 

Shublik Formation. USGS colin. 33119. 

Other levels .-Anisian?, Ladinian through Norian, from 

25.9 to 154.4 m (85-477 ft) above the base of the Shublik 

Formation. 

Diagnosis .-Elongated; dorsal margin evenly convex, 

ventral margin gently convex; end margins rounded, posterior broader than anterior. Dorsal outline subelliptical, anterior narrower than posterior, lateral sides evenly convex, 

greatest width at or behind midlength, h/1 index less than 

0.700. 

Description.-The holotype, a carapace with a fragment 

of the shell missing on the posterior of the left valve, has a 

relatively thick shell as shown on plate 8, figures 12 and 14. 

The dorsal margin of the larger valve does not overreach and 

overlap the smaller valve as much as the ventral margin does 

(pl. 8, figs. 1, 12). The greatest convexity of the anterior 

margin of the left valve is lower in relation to the height than 

that of the posterior margin (pl. 8, figs. 14, 18; pl. 9, fig. 

2; pl. 10, figs. 3, 5). The denticulate hinge ofthe right valve 

is not as distinctly tripartite (pl. 5, figs. 20-22) as it is in 0. 

owthropensis (Anderson, 1964) (Anderson, 1964, pl. 14, 

fig. 101; Bate, 1978, pl. 1, fig. 15), as well as in the 

Hungarian 0. sp. illustrated herein (pl. 10, figs. 12, 13). 

Although the adductor muscle scar is poorly preserved (pl. 

8, figs. 18, 19; pl. 10, fig. 5), the aggregate outline is 

typical of Ogmoconcha. 

Measurements (in mm) (R. V. =right valve; 

B = steinkern).-

Greatest Greatest Height/ 

length height length 

USNM 389883 0.33 0.21 0.636 

USNM 389888, R. V. .42 .24 

USNM 389911 .43 .25 .581 

USNM 389866 .44 .30 .682 

USNM 389901 .44 .30 .682 

USNM 389858, R. V. .44 .30 

USNM 389903, R. V. .45 .30 

USNM 389910 .46 .27 .587 

USNM 389876 .46 .31 .674 

USNM 389899, B .48 .27 .563 

USNM 389862 .50 .30 .600 

USNM 389875 .50 .32 .640 

USNM 389864 .50 .33 .660 

USNM 390004 .59 .30 .508 

USNM 389865 .60 .40 .667 

USNM 389863 .60 .40 .667 

Middle And Upper Triassic Marine Ostracoda, Northeastern Alaska C17 
Discussion.-The carapace from the Austrian Alps that 

was illustrated by Urlichs (1972, pl. 4, fig. 6) resembles a 

paratype illustrated herein (pl. 8, figs. 15-19) in lateral 

outline and in apparent surface punctation. I attribute the 

relatively thin shell of the illustrated specimen to corrosion 

which removed part of the outside of the shell. Urlichs' 

specimen also represents a corroded carapace as indicated 

by the missing shell material along the dorsoanterior margin. The puncta that are present on the anterior half on my 

specimen and that are barely visible on the posterior half of 

Urlichs' illustration are interpreted to be cross sections of 

normal pores. 

Geologic range .-Anisian?, Ladinian through Norian, 

from 25.9 to 145.4 m (85-477 ft) above the base of the 

Shublik Formation. The Anisian age is questioned because 

USGS colln. 33106, from which a carapace (USNM 

389916) was recovered, is located below the Ladinian as 

determined by megafossils. 

Ogmoconcha marquardti n. sp. 

Plate 9, figures 5-8; plate 10, figures 23-32 

Etymology of name .-In honor of Mr. J. F. Marquardt, 

Reference Librarian, Smithsonian Institution Libraries, 

whose expert and cooperative assistance for more than 25 

years is greatly appreciated. 

Holotype .-USNM 389905. 

Paratype .-USNM 389882. 389889. 

Type level.-Norian, clay shale member, from 128.0 to 

129.5 m (420-425 ft) above the base of the Shublik Formation. USGS colin. 33158. 

Other level.-The same member as above, from 121.9 to 

123.4 m (400-405 ft) above the base of the Shublik Formation. USGS colin. 33154. 

Diagnosis .-Differs from all other species of Ogmoconcha in subtriangular lateral outline, the anterior margin being much higher than the posterior margin. 

Description.-The carapaces are small, less than 0.5 mm 

in greatest length. The hingeline is almost straight; it extends forward from the posterior margin to about two-thirds 

of the greatest length of the valves. The anterior margin is 

broadly rounded and is about twice the height of the posterior margin, and its greatest convexity is located below the 

hingeline at or lower than the junction of the posterior margin with the ventral margin. The ventral margin curves 

steeply backward and upward to meet the posterior margin. 

The left valve overlaps the right along the free margins and 

overreaches slightly along the hinge margin. The paratype 

(pl. 10, figs. 23-26) lacks a small part of the right valve at 

the dorsoposterior, where the denticulated hinge is exposed 

(pl. 10, figs. 23, 26). 

Measurements (in mm).-USNM 389882, greatest 

length 0.23, greatest height 0.17, h/1 0. 739; USNM 

389889, greatest length 0.43, greatest height 0.30, h/1 

0.750; USNM 389905, greatest length 0.45, greatest height 

0.35, h/1 0. 778. 

C18 Shorter Contributions to Paleontology and Stratigraphy 

Discussion .-Although only two carapaces and one 

steinkem of this species have been recovered, they differ in 

lateral outline from the described species in Ogmoconcha, 

thus warranting their description as a new species. Both 

carapaces have what appears to be a minute ventroposterior 

spine on the right valve (pl. 10, figs. 24, 28, 29). Because 

both carapaces are covered with adhering grains of an undetermined mineral, I did not use the presence of the 

spinelet(?) as an additional specific character. A minute 

steinkem (pl. 9, figs. 5-8) is referred to this species because 

of its lateral outline. Although the adductor muscle scar of 

specimens is unknown, this species is referred to Ogmoconcha because of the external morphology. 

The Lower Pliensbachian (Jurassic) 0. eocontractula 

Park, 1984, from Europe, has a triangular lateral outline, 

but that species (0.87-0.91 mm long) is much larger than 0. 

marquardti , its ventral margin is not as truncated towards 

the posterior, and both valves have spinelets along the anterior margin-features that differentiate the two species. 

Cytherella inaequata Donze, 1966, as illustrated by Blaszyk 

and Gazdzicki (1982, p. 133, pl. 46, fig. 2) from the Hettangian (Late Jurassic) of Poland, differs from Donze's 

( 1966) species in having a triangular lateral outline similar 

to the new species. This unnamed species is larger than 0. 

marquardti (L = 0. 76 mm), and it has an obtuse posterior in 

dorsal outline. 

Geologic range .-Norian, clay shale member, from 

119.3 to 129.5 m (365-425 ft) above the base ofthe Shublik 

Formation. 

Ogmoconcha sp. 

Plate 10, figures 12-14 

Ogmoconcha n. sp. Sohn, 1984b, p. 21, fig. llE-G, 

Carnian, Hungary. 

Discussion .-See discussion under 0. unicerata n. sp. 

Kozur's species, however, does not have a denticulated 

hinge and does not belong to Ogmoconcha . The Hungarian 

species is not formally named and described because study 

of Hungarian material is beyond the scope of this paper. The 

Upper Triassic (Carnian) taxon illustrated herein has a tripartite denticulate hinge, suggesting that 0. unicerata from 

Alaska is not related on the generic level with the Anisian 

and Ladinian specimens illustrated by Kozur ( 1970a, p. 22, 

pl. 4, figs. 15-17) as 0 gmoconcha reniformis (Mehes, 

1911). 

Measurements (in mm).-USNM 389999, greatest 

length 0.70, greatest height 0.50, h/1 0.714. 

Geologic range .-Carnian (Upper Triassic), Hungary. 

USGS colin. 33172. 

Ogmoconcha? sp. afT. Hungarella limbata 

(Reuss, 1868) sensu Urlichs, 1971 

Plate 3, figure 7 

Cytherella limbata Reuss, 1868, p. 108 (no illustration). 

Cassinian, Italy. 
Hungarella limbata (Reuss, 1868) Urlichs, 1971, p. 707, 

pl. 1, figs. 3-14, text figs. 4-6. Cassinian, Italy (topotypes). 

?Ogmoconcha sp. Sohn, 1968, p. 29, pl. 3, figs. 1-3, 8. 

Ladinian, Italy. 

Discussion .-Because only one left valve on matrix from 

the Ladinian part of the Shublik Formation ( 63.6-65.2 m 

above the base) is available, the species is not named. The 

specimen is probably a left valve because of the well developed dorsal pleat and narrower ventral pleat or rim. This 

specimen differs from the left valves illustrated by Urlichs 

( 1971 , pl. 1, figs. 3, 5, text fig. 4) in lateral outline and size 

of dorsal pleat. Because the interior of the valve is obscured 

by rock, neither the hingement nor the adductor muscle scar 

can be determined; it is only questionably referred to Ogmoconcha. To orient the specimen for measurement, an attempt to smooth the rock below the valve resulted in breaking the anteroventral part of the shell. Approximate 

measurements are 0.8 mm long and 0.6 mm high. 

Because Reuss (1868, p. 108) did not illustrate Cytherella 

limbata, that species was listed as "Gen. and sp. indet." 

(Sohn, 1968, p. 45), and the illustrated specimens were 

identified as Ogmoconcha sp. (Sohn, 1968, pl. 3, figs. 1-3, 

8). Unfortunately, the valve illustrated on fig. 8 is lost; 

consequently, only the three remaining carapaces illustrated 

above could be measured to compare them with Urlichs' 

measurements of an ontogenetic series. 

Urlichs (1971, p. 708) stated that his collections were 

from Reuss' type locality, and he identified and illustrated 

the species based on the original description. He described 

the right valve as having a small ventroposterior spine 

(1971 , pl. 1 , figs. 7, 8, 11) and a narrow frill along the 

anterior margin. The anterior marginal frill is not discernible 

on the thn~e carapaces from Italy in the National Museum. 

The illustrated carapace (Sohn, 1968, pl. 3, fig. 2) has a 

minute posteroventral spine not seen on the published magnification of X30, but the other two carapaces do not have 

that spine preserved. 

Only the specimens discussed above have pleats on the 

left valve; all the other species in Ogmoconcha have smooth 

left valves. Figure 7 was included on the plate that illustrates 

specimens of the Ussuricavininae Gramm, 1969, to suggest 

that these Ogmoconcha specimens are possible relatives of 

the Ussuricavininae, a subfamily that is poorly known. 

Measurements (in mm).-Plate 3, figure 7, USNM 

38983 7, greatest length 0. 8, greatest height 0. 6, hi 1 0. 7 50. 

Specimens from Italy, USNM 147198, greatest length 0.62, 

greatest height 0.55, h/1 0.887; USNM 147199, greatest 

length 0.65, greatest height 0.52, h/1 0.800; USNM 

147200, greatest length 0.65, greatest height 0.56, h/1 

0.862. 

Geologic range .-Ladinian, limestone and dolomite 

member, from 63.6 to 65.2 m (210-215 ft) above the base 

of the Shublik Formation. 

Order PLA TYCOPIDA Sars, 1866 

Suborder PLATYCOPINA Sars, 1866 

Superfamily CA VELLINACEA Egorov, 1950 

Family CA VELLINIDAE Egorov, 1950 

Discussion. -Sohn (1968, p. 17) discussed the above 

classification. 

Subfamily USSURICA VININAE Gramm, 1969 

Discussion .-Gramm (1969b, p. 55) described this subfamily for the Triassic marine genera Ussuricavina Gramm, 

1969, Orlovicavina Gramm, 1969, and Cavussurella 

Gramm, 1969. The following year, Gramm (1970, p. 100) 

established the subfamily Recytellinae in the family 

Cytherellidae Sars, 1866, for the Middle Triassic genera 

Recytella Gramm, 1970, and Recytelloidea Gramm, 1970. 

Kozur (1972b, p. 18) considered Cavussurella Gramm, 

1969, and Recytella Gramm, 1970, to be synonyms of 

Reubenella Sohn, 1968; Orlovicavina Gramm, 1969, to be 

a synonym of Issacharella Sohn, 1968; and Recytelloidea 

Gramm, 1970 to be a synonym of Leviella Sohn, 1968-all 

in the family Cytherellidae Sars, 1866. Sohn (1968, p. 21) 

questionably referred Leviella to the Cytherellidae Sars, 

1866, because the adductor muscle-attachment scar pattern 

of this genus was not known. Kristan-Tollmann (1973, 

p. 360, 363, 370) illustrated aggregate adductor muscleattachment scars of several species of Triassic (Carnian) 

Levie/la similar to those in the Cavellinacea as defined in 

Moore (1961, p. Q368) but not to those in the Cytherellacea 

as defined in Moore (1961, p. Q382). 

The subfamily Recytellinae Gramm, 1970, was defined 

as having an external depression on the ventral portion of the 

brood pouch on each female valve (Gramm, 1970, p. 100), 

a feature absent in the Ussuricavininae. Cavussurella and 

Recytella are considered in this study to be valid genera. 

Geologic range .-Middle and Upper Triassic. 

Geographic distribution. -Primor'ye Territory, 

U.S.S.R., and northeastern Alaska. 

Genus CA VUSSURELLA Gramm, 1969 

Cavussurella Gramm, 1969b, p. 72. 

Type species .-C. kramtchanini Gramm, 1969b, p. 72, 

pl. 5, figs. 5-15; pl. 6, fig. 8; pl. 8, figs. 1-24; text fig. 3.8. 

Upper Anisian, Primor'ye Region, U.S.S.R. 

Original diagnosis (translated).-"Middle-sized Ussuricavininae, with variable oval outlines, elongated or shortened. Unequivalved. Surface pitted punctate. Adductor scar 

consists of three or four rows of spots; rows 1 and 2 prominent, posterior rows considerably reduced." 

Discussion.-The holotype of C. kramtchanini Gramm 

(1969b, pl. 5, fig. 14) is a possible juvenile right valve 

0. 775 mm long and 0.520 mm high. A paratype, the carapace of a male (Gramm, 1969b, pl. 5, figs. 15a-d), 0.925 

mm long, 0.575 mm high, and 0.350 mm wide was illustrated in right, left, dorsal, and ventral views. Both speci- · 

mens have a weak subcentral pit and a marginal rim that is 

Middle And Upper Triassic Marine Ostracoda, Northeastern Alaska C19 
stronger along the convex dorsal and ventral margins similar 

to the specimens illustrated herein. Gramm did not illustrate 

or describe the dimorphism observed in the present specimens from Alaska. 

Gramm did not describe the hingement of Cavussurella. 

A fragment of a valve that is herein provisionally assigned 

to Cavussure/la in informal nomenclature as Cavussurella? 

sp. 1 (pl. 10, fig. 9; pl. 11, figs. 25, 26) has a welldeveloped ridge and groove along the hinge and a groove 

along the venter to receive the smaller valve similar to the 

ventral groove shown on plate 4, figure 16. Fragments and 

a steinkem of a valve (pi 10, fig. 9; pl. 11, figs. 25-27) that 

differ in lateral outline from Cavussure/la grammi n. sp. are 

illustrated in informal nomenclature as Cavussurella? spp. 

Geologic age .-Middle and Upper Triassic. 

Geographic distribution .-Primor'ye Territory, 

U.S.S.R., and northeastern Alaska. 

Cavussurella grammi Sohn, n. sp. 

Plate 3, figures 8-21 ; plate 4, figures 1-21 

Etymology of name .-In honor of Dr. M. N. Gramm, 

Vladivostok, U.S.S.R. 

Holotype .-A damaged female carapace, USNM 

389845. 

Paratypes .-USNM 389838-389844, 389846-389849, 

389854, 390039. 

Type /eve/.-Ladinian, limestone and dolomite member, 

from 48.8 to 50.3 m (160-165 ft) above the base of the 

Shublik Formation. 

Diagnosis .-Differs from Cavussurella kramtchanini 

Gramm, 1969b, in that the posterior margin is more broadly 

rounded, dimorphic in width of posterior. 

Description. -Although the specimens are poorly preserved, the following composite conception of the new species can be constructed. The valves are relatively thick 

(pl. 3, figs. 13, 14, 15-17, 18, 19; pl. 4, figs. 14, 18), 

subovate, almost elliptical. The dorsal and ventral margins 

are gently convex and are of approximately the same curvature and height. The right valve overlaps the left slightly 

along the ventral margin (pl. 3, figs. 16, 17; pl. 4, figs. 3, 

12-14) and overreaches along the dorsal margin (pl. 4, figs. 

5, 10); it is more convex along the dorsum than the smaller 

left valve (pl. 4, fig. 2). The right valve has a thicker 

marginal rim than the left valve (pl. 4, figs. 1, 3, 10-15), 

and the rim is more pronounced along the dorsum than along 

the ventral margin and is subdued along the end margins 

(pl. 3, figs. 14, 15; pl. 4, figs. 3, 4, 10, 14). The species is 

dimorphic in dorsal outline; the heteromorphs (females) are 

widest near the posterior (pl. 4, fig. 12), and the tecnomorphs (males and juveniles) are widest behind midlength (pl. 3, figs. 15, 18; pl. 4, figs. 1, 3, 9). One juvenile 

(pl. 4, figs. 1-5) has a punctate surface, and it is assumed 

that the smooth specimens were also punctate. The adductor 

muscle scar is not preserved, except possibly on the 

steinkem of the left valve (pl. 3, fig. 20) where it is too 

C20 Shorter Contributions to Paleontology and Stratigraphy 

poorly preserved to determine the individual rows of spots. 

Fragments and steinkems from the same collection as the 

paratypes (USGS colln. 33132) are tentatively referred to 

this species (USNM 390039). Because the genus is based 

primarily on the adductor muscle scar of the type species, 

the illustrations and a preliminary draft of the description of 

this species were sent to Prof. M. N. Gramm who very 

kindly compared the illustrations with the holotype and 

paratypes of C. kramtchanini. He stated (written commun., 

July 12, 1984) that, in his opinion, the forms are congeneric. 

Measurements (in mm) (unfigd. = unfigured specimen, 

L. V. = left valve).-

Greatest length Greatest height 

USNM 389843 0.53 0.32 

USNM 389839 .60 .36 

USNM 389841 .60 .40 

USNM 389844 .70 .40 

USNM 389840 .70+ .50 

USNM 38954 .75 .50 

USNM 389842 .75+ .5+ 

USNM 389838 .8+ .4+ 

USNM 389845 .8+ .5+ 

USNM 390039, .80 .60 

unfigd., L. V. 

Geologic range .-Ladinian to Norian, from 36.6 to 

145.4 m (120-477 ft) above the base of the Shublik Formation. 

Cavussurella? spp. 

Plate 10, figure 9; plate 11, figures 25-27 

Discussion .-Fragments and steinkems of specimens 

that cannot be assigned with certainty to Cavussurella 

grammi are provisionally assigned to the genus. A fragment 

of a left valve (pl. 10, fig. 9; pl. 11, figs. 25, 26) and a 

steinkem of a left valve (pl. 11, fig. 27) are illustrated. 

The fragment (pl. 10, fig. 9; pl. 11, figs. 25, 26), illustrated as Cavussurella sp. 1, has a relatively thick shell 

similar to C. grammi shown on plate 3, figures 13-21, and 

plate 4, figures 10-21, and has a pleat below the dorsal 

margin similar to those on plate 3, figure 10, and plate 4, 

figure 11. The hinge consists of a groove (pl. 10, fig. 9; pl. 

11, fig. 26) hitherto not known in Cavussurella because 

neither Gramm ( 1969b) nor I have been able to observe the 

hingement on specimens of this genus. The groove along the 

venter for the reception of the smaller valve resembles the 

groove exposed on broken carapaces of C. grammi (pl. 3, 

figs. 16, 17; pl. 4, figs. 14, 15, 18). Neither ofthe two spots 

seen on plate 11, figure 26, represents the adductor muscle 

scar when examined in the SEM at X500. 

The steinkem of a left valve, illustrated herein as Cavussurella? sp. 2 (pl. 11, fig. 27), differs in lateral outline from 
C. grammi, as does a second damaged steinkern (USNM 

389850). 

Measurements (in mm).-USNM 389851, greatest 

length 0. 7 +, greatest height 0. 60; USNM 389003, greatest 

length 0.80, greatest height 0.50; unfig. steinkern USNM 

389850, greatest length 0. 7 +, greatest height 0.40. 

Geologic range .-Ladinian, limestone and dolomite 

member, from 45.7 to 64.0 m (155-215 ft) above the base 

of the Shublik Formation. 

Subfamily RECYTELLINAE Gramm, 1970 

See discussion under the U ssuricavininae. 

Genus RECYTELLA Gramm, 1970 

Type species .-R. amnekhoroshevi Gramm, 1970, 

p. 101. text fig. 1, pl. 4, figs. 1-9. Ladinian (AGI translation, p. 86), Primor'ye Territory, U.S.S.R. 

Diagnosis .-"Cytherellid Recytellinae of average size. 

Inequivalvular. The adductor scar is of complex structure 

consisting of a double-row group and is in the stage of 

reduction of the supernumerary maculae." 

Discussion .-As stated in the discussion ofthe subfamily 

U ssuricavininae, Kozur ( 1972b) considered Cavussurella 

and Recytella to be junior synonyms of Reubenella. He 

stated (1972b, p. 19) that Ussuricavina Gramm, 1969b, and 

the Ussuricavininae belong in the Cavellinidae and that the 

Recytellinae, including Reubenella, belong to the Cytherellidae. The females (heteromorphs) of Reubenella have a 

ventroposterior lobe on the outside of the valves (Sohn, 

1968, pl. 1, figs. 40, 43-45) that are represented on the 

inside by distinct cavities (Sohn, 1968, pl. 4, fig. 12). These 

cavities are lobes on steinkerns as illustrated herein (pl. 2, 

figs. 1-13) and by Gramm (1969b, pl. 4, figs. 1a, b, 4a). 

The adductor muscle-attachment scar of Recytella 

Gramm, 1970, consists of four rows of scars (Gramm, 

1970, text fig. 1, pl. 4, figs. 4-9), including the supplementary maculae. 

The adductor muscle scar of Reubenella Sohn, 1968, 

consists of more than four rows (Sohn, 1968, pl. 4, fig. 12). 

The adductor muscle scars illustrated herein (pl. 2, figs. 2, 

3, 5) are similar in pattern to the adductor muscleattachment scar illustrated by Gramm for Recytella and document the presence of Recytella in Alaska. Because of very 

poor preservation and inadequate material, the specimens 

from Alaska are placed in open nomenclature. 

Geologic range.- Middle Triassic (Anisian-Ladinian). 

Geographic distribution. -Primor'ye Territory, 

U.S.S.R., and northeastern Alaska. 

Recytella sp. 1 

Plate 2, figures 1-9 

Discussion.-The adductor muscle scar illustrated on 

plate 2, figure 5, and the posterolateral bulge shown on 

figures 2, 4, 6, 8, 9 identify the two steinkerns as belonging 

in Recytella . 

Measurements (in mm).-USNM 389810, greatest 

length 0. 72 + , greatest height 0.41 +; USNM 389811, 

greatest length 0. 7 +, greatest height 0.4+. 

Geologic range .-Ladinian, limestone and dolomite 

member, from 56.4 to 67.1 m (185-220 ft) above the base 

of the Shublik Formation. 

Recytella sp. 2 

Plate 2, figures 10-13 

Discussion.-The illustrated specimen appears to have 

shell material retained on the right valve. The fact that this 

apparent shell material extends on the left over the area of 

the impression of the ventral contact on the steinkern 

(figs. 10, 11, 13) suggests that this is neither original nor 

replaced shell material. A steinkern of a left valve and the 

inside of a damaged left valve in USGS colln. 33132 

(USNM 390010) probably belong to this taxon. 

Measurements in (mm).-USNM 389812, greatest 

length 0. 72, greatest height 0. 5 + ; unfigd. spec. USNM 

3900 10, greatest length 0. 71 , greatest height 0.44. 

Geologic range .-Ladinian, limestone and dolomite 

member, from 67.1 to 68.6 m (220-225 ft) above the base 

of the Shublik Formation. 

REFERENCES 

Anderson, F. W., 1964, Rhaetic Ostracoda: Great Britain Geological Survey Bulletin 21, p. 133-174, pis. 8-15. 

--- 1970, Carboniferous Ostracoda-The genus Carbonita 

Strand: Great Britain Geological Survey Bulletin 32, p. 69-

121. 

Bate, R. H., 1978, The Trias, in Bate, R. H., and Robinson, Eric, 

eds., A stratigraphical index of British Ostracoda: Geological 

Journal, Special Issue 8, p. 175-188, 2 pis. 

Blaszyk, Janusz, and Gazdzicki, Andrzej, 1982, Lower Lias ostracodes of the Tatra Mts. (West Carpathians): Acta Palaeontologica Polonica, v. 27, no. 1-4, p. 129-136, pis. 46, 47. 

Blome, C. D., and Reed, K. M., 1984, Mesozoic radiolarian 

biostratigraphy of the Brooks Range, northern Alaska [abs.]: 

Geological Society of America, Abstracts with Programs, 

v. 16, no. 5, p. 271. 

Boda, Jeno, 1964, Catalogus originalum fossilium Hungariae. 

Pars Zoologica: Magyar Allami Foldtani Intezet Budapest, 

229 p. 

Bolz, Heiner, 1971a, Die Zlamback-Schichten (alpine Obertrias) 

unter besonderer Beriicksichtigung der Ostracoden. 1: Ostracoden der Zlambach-Schichten, besonders Bairdiidae: Senckenbergian Lethaea, v. 52, p. 129-283, 16 pis. 

---1971b, Late Triassic Bairdiidae and Healdiidae, in Oertli, 

H. J., ed., Colloque sur Ia paleoecologie des ostracodesColloquium on the paleoecology of ostracodes, Pau. 20-27, 

VII, 1970: Centre de Recherches de Pau-SNPA Bulletin, v. 5, 

supplement, p. 717-745, 4 pis. 

Burij, I. V., and Zharnikova, N. K., 1977, Paleobiogeograficheskoe raionirovanie basseina Tikhogo okeana v triasovoe 

vremya [Triassic biogeography of the Pacific Ocean 

basin], in Krassilov, V. A., ed., Evolyutsia organichMiddle And Upper Triassic Marine Ostracoda, Northeastern Alaska C21 
eskogo mira tikhookeanskogo poyasa [Organic evolution 

in the Circum-Pacific belt]: Vladibvostok, Akademia 

Nauk SSSR, Dal'nevostochnyi Nauchnyi Tcentr BiologoPochvennye Institute [Academy of Sciences, Far-eastern 

Scientific Centre, Institute of Biology and Pedology), 

p. 89-113. 

Choi, D. R., 1984, Late Permian-Early Triassic paleogeography of 

northern Japan: Did the Pacific microplates accrete to Japan: 

Geology, v. 12, p. 728-731, 5 figs. 

Churkin, Michael, Jr., 1972, Western boundary of the North 

American continental plate in Asia: Geological Society of 

America Bulletin, v. 83, no. 4, p. 1027-1036, 5 figs. 

Churkin, Michael, Jr., and Trexler, J. H., Jr., 1981, Continental 

plates and accreted oceanic terranes in the Arctic, in Nairn, 

A. E. M., Churkin, Michael, Jr., and Stehli, F. G., ed., The 

ocean basins and margins-The Arctic Ocean: New York, 

Plenum Press, v. 5, p. 1-20, 12 figs. 

Cooper, C. L., 1941, Chester ostracodes of Illinois: Illinois State 

Geological Survey Report of Investigations 77, 101 p., 14 

pls. 

Coryell, H. N., 1963, Bibliographic index and classification of the 

Mesozoic Ostracoda: Dayton, Ohio, University of Dayton 

Press, v. 2, p. 379-1175. 

Dadlez, Ryszard, and Kopik, Janusz, 1963, Problem retyky w 

zachodniej Poise na tle profilu w kssiazu Wielkopolskim 

[Problem of the Rhaetic in Western Poland in the light of the 

profile at ksiaz Wielkopolski]: K wartalnik Geologiczny, v. 7. 

no. 1, p. 131-158, 2 pls. (Polish, English summary.) 

Delo, D. M., 1930, Some Upper Carboniferous Ostracoda from 

the shale basin western Texas: Journal of Paleontology, v. 4, 

no. 2, p. 152-178, pls. 12, 13. 

Detterman, R. L., Reiser, H. N., Brosge, W. P., and Dutro, J. T., 

Jr. , 197 5, Post -Carboniferous stratigraphy, northeastern 

Alaska: U.S. Geological Survey Professional Paper 886, 

46 p., 14 figs. 

Donze, Pierre, 1966, Ostracodes de l'Hettangien entre Aubenas et 

Privas (Ardeche): Laboratories de Geologie de la Faculte des 

Sciences de Lyon, Travaux, new series, no. 13, p. 121-

139, pls. 5-7. 

Dreyer, Eva, 1965 [1967], Mikrofossilien des Rotund Lias von 

SW-Brandenburg: Jahrbuch Geologie, v. 1, p. 491-531, 9 

pls. 

Dutro, J. T. Jr., 1981, Geology of Alaska bordering the Arctic 

Ocean, in Nairn, A. E. M., Churkin, Michael, Jr., and 

Stehli, F. G., eds., The ocean basins and margins-The 

Arctic Ocean: New York, Plenum Press, v. 5, p. 21-36, 

Egorov, V. G., 1950, Ostrakody Franskogo Y arusa Russkoi Platformy [Ostracoda of the Frasnian Stage of the Russian Platform]. 1. Kloedenellidae: Moscov, V sesoyuznyi Neftyanoi 

Nauchno-Issledovatel' skii Geologo-Razvedochnyi Institut, 

Moscovskii Filial, 140 p., 18 pls. 

Fischer, M. J., 1984, Triassic, in Glennie, K. W. ed., Introduction 

to the petroleum geology of the North Sea: London, Blackwell Scientific Publications, p. 85-101, 12 figs. 

Gerry, Ephraim, and Kozur, Heinz, 1973, Original of Mehes, 

1911, "Uber Trias-Ostracoden aus dem Bakony" at the Hungarian Geological Institute: Foldtani Kozlony, v. 103, p. 67-

69. 

Gheorghian, Doina, 1976, Contributii la cunoasterea unor microfaune Triasice din Muntii Apuseni (Padurea Craiului) [Contributions ala connaisance d'une microfaune Triassique des 

Monts Apuseni (Padurea Craiului)]: Rumania, Instutal de 

Geolgie si Geofizica Dari de Seama ale ~edintelor, Paleontologie, v. 62 (1974-1975), [pt.] 3, p. 25-38, pls. 7-9. 

Gramm, M. N., 1969a, Otpechatki adduktora Healdiidae (Ostracoda) iz srednego triassa Yuzhnogo Primor'ya [Casts of the 

adductor of Healdiidae (Ostracoda) from the Middle Triassic 

of the South Maritime Territory]: Akademia Nauk SSSR, 

Doklady, 1969, v. 186, no. 2, p. 457-460, 4 figs. (English 

translation by American Geological Institute, 1970, no. 2, 

p. 234-257.) 

--- 1969b, Ussuricavininae-Novoe podsemeistvo Triassovykh ostrakod, in Gramm, M. N. and Krasilov, V. A., 

eds., Iskopaemaya fauna i flora Dal'nego Vostoka: Vlkadivostok, Akademia Nauk SSR Sibirskoe Otdelenie, 

Dal'nevostchnyi filial im. V. L. Komarova, Dal'nevostochnyi 

Geologicheskii Institut, p. 41-78, ps. 3-8. 

-- 1970, Otpechatki adduktora Triasovykh cytherellid (Ostracoda) Primor'ya i nekotorye voprosy teorii fllembriogeneza. 

[Adductor scars on Triassic cytherellid (Ostracoda) from the 

Maritime Territory and problems of phylembryogenesis]: Paleontologicheskii Zhurnal, 1970, no. 1, p. 88-103, pl. 6. (English 

translation by American Geological Institute Paleontological 

Journal, 1970, v. 4, no. 1, p. 76--90.) 

--- 1975, Marine Triassic Cytheracea (Ostracoda) from south 

Primor'ye [Soviet Far East]: Paleontographica, pt. A, v. 151, 

p. 102-110, 1 pl. 

--- 1982, The systematic position of the ostracod genus Healdianella Posner, 1951, in Bate, R. H., Robinson, Eric, and 

Sheppard, L. M., eds., Fossil and recent ostracods: 

Chichester, Ellis Horwood Ltd., for the British Micropalaeontological Society, p. 193-218, 5 pls. 

Grantz, Arthur, Johnson, Leonard and Sweeny, J. F., 1982, The 

Arctic region, in Palmer, A. R., ed., Perspectives in regional 

geological planning for the geology of North America: Geological Society of America, D-NAG Special Publication 1, 

p. 105-115. 

Griindel, Joachim, 1967, Zur Grossgliederung der Ordnung Podocopida G. W. Miiller, 1894 (Ostracoda): Neues Jahrbuch fiir 

Geologie and PaHiontologie, Monatshefte, Jahrgang 1967, 

no. 6, p. 321-332. 

Harlton, B. H., 1933, Micropaleontology of the Pennsylvanian 

Ostracoda of the Johns Valley shale of the Ouachita Mountains, Oklahoma, and its relationship to the Mississippian 

Caney Shale: Journal of Paleontology, v. 1, p. 3-29, 7 pls. 

Hartmann, Gerd, 1964, Zur Kenntnis der Ostracoden des Roten 

Meeres: Kieler Meeresforschungen, v. 20, p. 35-127, 62 

pls. 

International Commission on Zoological Nomenclature, 1985, International Code of Zoological Nomenclature: London, International Trust for Zoological Nomenclature, 338 p. 

Jones, D. L., Silberling, N.J., and Hillhouse, J. W., 1978, microplate tectonics of Alaska-Significance for the Mesozoic 

history of the Pacific coast of North America, in Howell, 

D. G., and McDougall, K. A., eds., Mesozoic paleogeography of the Western United States: Los Angeles, Society of 

Economic Paleontologists and Mineralogists, Pacific section, 

p. 71-74. 

Jones, T. R., 1894, On the Rhaetic and some Liassic Ostracoda of 

Britain: Geological Society of London Quarterly Journal, 

v. 50' p. 156-169, pl. 9. 

Jones, T. R., and Kirkby, J. W., 1886, On some fringed and other 
Ostracoda from the Carboniferous series: Geological 

Magazine, new series, Decade 3, v. 3, no. 10, p. 433-439, 

pls. 11, 12. 

Kniipfer, Jiitrgen, 1967, Editia germanica sp. n., eine neue Ostracodenart aus dem Untercarbon im Norden der DDR und zur 

Taxionomie der Familie Bythocytheridae Sars 1926: 

Deutsche Gesellschaft fiir geologische Wissenschaften, 

Berichte, A. Geologie und Palaontologie, v. 12, no. 3/4, 

p. 193-200, 1 pl. 

Kollmann, Kurt, 1960, Osrtakoden aus der alpinen Trias Osterreichs. I. Parabairdia n. g. und Ptychobairdia n. g. (Bairdiidae): Austria, Geologische Bundesanstalt Jahrbuch, Sanderband 5, p. 79-105, 6 pls. 

--- 1963, Ostracoden aus der alpinen Trias II. Weitere Bairdiidae: Austria, Geologische Bundensanstalt Jahrbuch, v. 106, 

p. 121-203, 11 pls. 

Kozur, Heinz, 1968a, Einige seltene Ostracoden-Arten aus der 

germanischen Trias: Deutsche Akademie der Wissenschaften 

zu Berlin, Monatsberichte, v. 10, no. 11, p. 849-872, 4 pls. 

--- 1968b, Neue Ostracoden aus dem Rot und Muschelkalk 

des germanschen Binnenbeckens: Deutsche Akademie der 

Wissenschaften zu Berlin, Monatsberichte, v. 10, no. 7, 

p. 448-519, 3 pls. 

--- 1970a, Neue Ostracoden-Arten aus dem obersten Anis des 

B akonyhochlandes ( U ngarn): N aturwis senschaftlichMedizinischer Verein, Berichte, v. 58, p. 1-40, 4 pis. 

--- 1970b, Neue Ostracoden-Arten der germanischen Mittel-und Obertrias: Geologie, Jahrgang 19, no. 4, p. 434-455, 

4 pis. 

--- 1971, Zur Verwertbarkeit von Conodonten, Ostracoden 

und Oekologische-Fazielle Untersuchungen in der Trias: Geologicky Sbomik, v. 22, no. 1, p. 105-130, 4 pls. 

--- 1972a, Die Bedeutung triassischer Ostracoden fiir 

stratigraphische und paliiookologische Untersuchungen: 

Geselllschaft Geologische Bergbaustudien Mitteilungen Innsbrock., v. 21, p. 623-660, 3 pls. 

--- 1972b, Einige Bemerkungen zur Systematik der Ostracoden und Beschriebung neuer Platytcopida aus der Trias Ungams und der Slowakei: Geologisch-PaHiontologische Mitteilungen Innsbruck, v. 2, no. 10, p. 1-27, 2 pis. 

--- 1973, Beitrage zur Stratigraphie und Paliiontologie der 

Trias: Geologisch-Paliiontologische Mitteilungen Innsbruck, 

v. 3, no. 1, p. 1-30, 3 pls. 

Kristan-Tollmann, Edith, 1964, Zur Charakteristik triadischer 

Mikrofaunen: Paliiontolgische Zeitschrift, v. 38, no. 112, 

p. 63--73, pls. 6, 7. 

--- 1970, Einige neue Bairdien (Ostracoda) aus der alpinen 

Trias: Neues Jahrbuch Geologie and Paliiontologie Abhandlungen, v. 135, no. 3, p. 268-310, pis. 33-37. 

--- 1971a, Torohealdia n. gen., eine characteristische 

Ostracoden-Gattung der obersten alpinen Trias: ErdolErdgas-Zeitschrift/Maratime Rohstoffgewinnung, v. 87, 

no. 2, p. 50-54, 1 pl. 

--- 1971 b, Weitere Beobachtungen an skulptierten Bairdiidae 

(Ostrac.) der alpinen Trias: Neues Jahrbuch Geologie und 

Paliiontologie Abhandlungen, v. 139, no. 1, p. 57-81, 5 pls. 

--- 1973, Zur Ausbildung des Schliesmuskelfelden bei triadischen Cytherellidae (Ostracoda): Neues Jahrbuch Geologie 

and Paliiontologie Monatschefte, Jahrgang 1973, v. 6, 

p. 351-373, 9 figs. 

--- 1977, On the development of muscle scar patterns in 

Triassic Ostracoda, in Loffler, Heinz, and Danielopol, Dan, 

eds., Aspects of ecology and zoogeography of Recent and 

fossil Ostracoda: The Hague, W. Junk, p. 133-143, 5 figs. 

--- 1979, Die Mikrofauna des Rhiit von W aliabad in KristanTollmann, Edith, Tollmann, Alexander, and Hamedani, Ali, 

Beitriige zur Kenntnis der Trias von Persien. 1, Revision der 

Triasgliederung, Rhiitfacies im Raum von Isfahan und 

Kassner Fazieseinschlag bei Waliabad SE Adadeh: Osterreichische geologische Gesellschaft Mitteilungen, v. 70, 1977, 

p. 119-186, 5 pls. 

Kristan-Tollman, Edith, and Hamedani, Ali, 1973, Eine specifische Mikrofaunen-Vergsellschaftung aus den Opponitzer 

Schichten des Oberkam der niederosterreichischen Kalkvoralpen: Neues Jahrbuch Geololgie und PaHiontologie Abhandlungen, v. 143, no. 2, p. 193-222, 13 figs. 

Kristan-Tollmann, Edith, and Tollmann, Alexander, 1981, Die 

Stellung der Tethys in der Trias und die Herkunft ihrer Fauna: 

Osterreichische geologische Gesellschaft, Mitteilungen, 

V. 74/75, (1981182), p. 129-135, 1 fig. 

--- 1983, Tethys-Faunenelemente in der Trias der USA: 

Oesterreichische geologische Gesellschaft, Mitteilungen, v. 

76, (1983), p. 213-272, 17 pls., 15 figs. 

Lord, Alan, 1972, The ostracode genera Ogmoconcha and Protocytheridea in the Lower Jurassic: Geological Society of Denmark Bulletin, v. 21, p. 319-336, 1 pl. 

--- 1982, Metacopine ostracodes in the Lower Jurassic, in 

Banner, F. T. , and Lord, Alan, eds. , Aspects of micropaleontology: London, George Allen & Unwin, p. 262-277, 4 

figs. 

Malz, Heinz, 1971, Zur Taxonomie "glattschaliger" LiasOstracoden: Senckenbergiana Lethaea, v. 52, no. 5/6, 

p. 433-455, 5 pls. 

Mandelstam, M. I., 1960, Stepene izuchenosti ostracod iz 

Permskikh, Triasovykh, Melovykh i Chetvetichnikh otlozhenii, in Subbotina, N. N. ed., Trudy pervogo seminara 

po mikrofaune: Leningrad, Vsesoyuznyi Neftyanoi 

N auchno-Issledovatel' skii Geologo-Razvedochnyi Institut 

(VNIGRI), Leningrad, p. 287-311. 

Mehes, Gyula, 1911, Ueber Trias-ostracodes aus dem Bakony: 

Resultate der Wissenschaftlichen Erforschung des Balatonsees. Balaton-Ausschusse der Ungarischen Geographischen 

Gesellschaft, v. 1, pt. 1, Anhang, Palaeontologie der Umgebung des Balatonsees, v. 3, no. 6, 38 p., 12 pis. 

Moore, R. C., ed., 1961, Treatise on invertebrate paleontology, 

pt. Q, Arthropoda 3, Crustacea, Ostracoda: New York and 

Lawrence, Kans., Geological Society of America and University of Kansas Press, New York and University Kansas 

Press, 422 p., 334 figs. 

Mull, C. G. , 1984, New interpretations on timing and origin of 

arctic Alaska block [abs.]: Geological Society of America, 

Abstracts with Programs, v. 16, no. 5, p. 323. 

Park, S. M., 1984, On Ogmosconcha eocontractula Park, sp. 

nov.: Stereo-atlas of ostracod shells, v. 11, no. 14, cards 

67-70. (London, British Micropaleontological Society.) 

Plafker, George, and Jones, D. L., 1982, Geology and tectonic 

evolution of Alaska, in Palmer, A. R., ed., Perspectives in 

regional planning for the geology of North America: Geological Society of America, D-NAG Special Publication 1, 

p. 77-80. 

Reuss, A. E., 1868, Foraminiferen und Ostracoden aus dem 

Schichten von St. Cassian: K. Akademie Wissenschaften, 
Mathematisch-Naturwissenschaftliche Klasse, Sitzungsberichte, v. 57, pt. 1, p. 101-108. 

Roundy, P. V., 1926, The microfauna, in Roundy, P. V., Girty, 

G. H., and Goldman, M. I., Mississippian formations of San 

Saba County, Texas: U.S. Geological Survey Professional 

Paper 146, p. 5-23, pis. 1-4. 

Sars, G. 0., 1866, Oversigt af Norges marine ostracoder: 

Videnskabs-Selskabets i Cristiania Forhandlinger (in 1865), 

130 p. 

---1888, Nye bidrag til kundskaben om Middelhavets invertebrat fauna: Archiv for Mathematik og Naturvidenskab, v. 12, 

pt. 4, p. 173-324, 20 pls. 

--- 1928, Ostracoda, v. 9 of An account of the Crustacea of 

Norway: Bergen, Norway, Bergen Museum, 277 p., 119 pis. 

(Originally published in parts as follows: Parts 1, 2-1922, 

pts. 3, 4-1923, pts. 5-12-1925, pts. 13, 14-1926, and 

pts. 15, 16 including title page, corrections, bibliography, 

and systematic list-1928.) 

Schneider, G. F., 1956, New genera, in Kiparisova, L. D., 

Markovsko, B. P., and Radchenko, G. P., eds., Novye semeistva i rody: Vsesoyuznyi Nauchno-Issledovatelskii Geologicheskii Institut (VSEGEI), Ministerstva Geologii i 

Okrany Nedr SSR, new series, Paleontologiya, no. 12, 

p. 120-127, pls. 19, 20, 22. 

Shaver, R. H. 1958, A study of Pseudobythocypris pediformis, a 

new name for an old ostracod: American Midland Naturalist, 

v. 59, no. 1, p. 120-137, 3 figs. 

Sohn, I. G., 1964, Significance of Triassic ostracodes from Alaska 

and Nevada: U.S. Geological Survey Professional Paper 

501-D, p. D40-D42. 

--- 1965, Classification of the superfamily Healdiacea and the 

genus Pseudophanasymmetria Sohn and Berdan, 1952 (Ostracoda): U.S. Geological Survey Professional Paper 525-B, 

p. B69-B72. 

--- 1968, Triassic ostracodes from Makhtesh Ramon, Israel: 

Israel Geological Survey Bulletin 44, 71 p., 4 pls. 

--- 1970, Early Triassic marine ostracodes from the Salt 

Range and Sughar Range, West Pakistan, in Kummel, 

Bernard, and Teichert, Curt, eds., Stratigraphic boundary 

problems-Permian and Triassic of West Pakistan: Kansas 

University, Department of Geology Special Publication 4, 

p. 193-206, 1 pl. 

--- 1976, Antiquity of the adductor muscle attachment scar in 

Darwinula Brady and Robertson, 1885, in Hartmann, Gerd, 

ed. , Proceedings of the 5th International Symposium on Ostracoda: Naturwissenschaftliche Verein in Hamburg Abhandlungen und Verhandlungen NF 18/19 (Supplement), p. 305-

308, 3 pls. 

--- 1977, Muscle scars of late Paleozoic freshwater ostracodes 

from West Viriginia: U.S. Geological Survey Journal of Research, v. 5, no. 1, p. 135-141, 3 figs. 

--- 1983, Ostracodes of the "Winifrede Limestone" (Middle 

Pennsylvanian) in the region of the proposed Pennsylvania 

System stratotype, West Virginia: Bulletins of American Paleontology, v. 84, no. 316, 53 p., 11 pls. 

--- 1984a, Marine Middle and Late Triassic Ostracoda in 

northern Alaska (abs. ): Geological Society of America, Abstracts with Programs, v. 16, no. 5, p. 334. 

--- 1984b, Tethyan marine Triassic ostracodes northeastern 

Alaska, in Reed, K. M., and Bartsch-Winkler, Suzan, eds., 

The United States Geological Survey in Alaska during 1982: 

U.S. Geological Survey Circular 939, p. 21-23, fig. 11. 

--- 1985, Late Mississippian (Namurian A) nonmarine ostracodes from West Virginia and Virginia: Journal of Paleontology, v. 59, no.2, p. 446---460, 6 figs. 

Stoll, R. N. , and others, 1961, International Code of Zoological 

Nomenclature: London, International Trust for Zoological 

Nomenclature, 176 p. 

Strand, Embrick, 1928, Miscellanea nomenclatorica zoologica et 

palaeontologica 1-11: Archiv fi.ir Naturgeschichte, v. 92 

(1926), Abt. A, no. 8, p. 30-75. 

Styk, Olga, 1972, Some more important new species of 

foraminifers and ostracodes from the Triassic deposits of 

Poland: Kwartalnik Geologiczny, v. 16, no. 4, p. 267-885, 

3 pls. 

--- 1979, Gromada Ostracoda Latreille, 1806, in Malinowskiej, Liddi, ed., Atlasa skamielnialosci przewodnich i 

charakterystycznych: Budowa geologiczna Polski, v. 3, 

no. 2a, Mezozoic, Trias, p. 107-126, pls. 24-34. 

--- 1982, Biostratigrafia osadow epikontynentalnego Triasu 

Polska na podstowie mal:ioraczk6w [Biostratigraphy of the 

epicontinental Triassic deposits of Poland based on the occurrence of ostracods]: Poland, Institut Geologiczny Bulletin, v. 

329, p. 5-62, 15 pls. 

Tappan, Helen, 1951, Foraminifera from the Arctic Slope of 

Alaska: U.S. Geological Survey Professional Paper 236-A, 

20 p. 

Tozer, E. T.,1982, Marine Triassic faunas of North AmericaTheir significance for assessing plate and terrane movements: 

Geologische Rundschau, v. 71, p. 1077-1104, 2 figs. 

Triebel, Erich, 1941, Morphologie und Okologie der fossilen Ostracoden: Senckenbergiana, v. 23, no. 4/6, p. 294-400, 

15 pls. 

Urlichs, Max, 1971, Variability of some ostracods from the Cassian beds (Alpine Triassic) depending on the ecology, in 

Oertli, H. J., ed., Colloque sur la paleoecologie des ostracodes-Colloquium on the Paleocology of ostracodes, Pau, 

2~27, VII, 1970: Centre de Recherches de Pau-SNPA, Bulletin, v. 5, supplement, p. 695-715, 1 pl. 

--- 1972 (1973), Ostracoden aus den Kossener Schichten und 

ihre Abhangigkeit von der Okologie: Gesellschaft Geologische Bergbaustudien Mitteilungen, v. 21, p. 661-710, 6 pls. 

(1973 fide Kristan-Tollmann, and Hamedani, 1973, p. 210). 

Vadasz, Elemer, 1933, Neuer Beitrag zur Frage der Triasforaminiferen in Bakony: Centralblatt Mineralogie, Geologie 

und Palaontologie, Jahrgang 1933, Abteilung B, no. 3, 

p. 173-178. 

Van Morkhoven, F. P.C. M., 1963, Post-Paleozoic Ostracoda: 

Their morphology, taxonomy, and economic use, v. 2, 

Generic descriptions: Amsterdam, Elsevier, 478 p. 

Wieber, C. A., 1951, Zur mikropalaontologischen Gliederung des 

nichtmarinen Rhat: Erdol und Kohle, v. 4, p. 755-760, 1 pl. 

Will, H.-J., 1969, Untesuchungen zur Stratigraphie und Genese 

des Oberkeupers in Nordwestdeutschland (posthumously 

edited by Graman, Friederich, and Plurnhoff, Franz): Geologische Jahrbuch, Beihefte, v. 54, 239 p., 4 pls. 

Ye Chun-hui, Gou Yun-xian, Hou You-tang, and Cao Mei-chen, 

1977, Mesozoic and Cenozoic ostracode fauna from Yunnan, 

China: Nanking Institute of Geology and Paleontology, fascicle 2, p. 153-384, 24 pls. (In Chinese.) 

Zahinyi, Bela, 1959, Ostracoden-Faunen aus der Aptstufe des 

Nordlichen Bakony-Gebirges: Hungary, Magyar Allami 

Foldtani Intezet Evkonyve, v. 47, fascicle 2, p. 357-563, 

6 pls. 
PLATES 1-11 

Contact photographs of the plates in this report are available at cost from U.S. 

Geological Survey Library, Federal Center, Denver, Colorado 80225 
PLATE 1 

FIGURES 1-9. "Hea/dia" sp. 1 

1-4. Posterior, right, dorsal (anterior to left), and ventral views of steinkem, approx. Xl20. Figured 

specimen, USNM 389803. Ladinian, USGS colln. 33123. 

5-9. Dorsal (anterior to right), right, detail of adductor muscle-attachment scar of right valve, left. and 

detail adductor muscle scar of left valve of steinkem, approx. X80, details approx. X280. Note 

frontal and dorsal muscle-attachment scars in figs. 7, 8. Figured specimen, USNM 389804. 

Ladinian, USGS colln. 33111. 

10-14. "Healdia" sp. 2. Dorsal (anterior to left), left, right, and ventral (anterior to right) views of steinkem, 

approx. X120. Figured specimen, USNM 389805. Ladinian, USGS colln. 33130. 

15-21. "Healdia" sp. 3. Detail of denticulated hinge in area shown by arrow on fig. 16, approx. X267, dorsal 

(anterior to left), posterior, detail of adductor muscle scar of left valve, approx. X400, detail of 

denticulated hinge in area shown by arrow on fig. 21, approx. X600, and right views of steinkem with 

retained parts of shell, approx'. X120. Figured specimen, USNM 389806. Ladinian, USGS colln. 

33110. 
U.S. GEOLOGICAL SURVEY BULLETIN 1664- C PLATE 1 

"HEALD/A" 
PLATE 2 

FICilJRES 1-9. Recytella sp. 1. 

1-5. Dorsal (anterior to left), right, left, and ventral (anterior to right) views of broken steinkem, 

approx. X80, detail of left adductor muscle-attachment scar, approx. X400. Figured specimen, 

USNM 389810. Ladinian, USGS colln. 33124. 

6-9. Dorsal (anterior to left), left, right, and ventral (anterior to right) views of steinkem, approx. X80. 

Figured specimen, USNM 389811. Ladinian, USGS colln. 33130. 

10--13. Recytella sp. 2. Left, ventral (anterior to left), dorsal (anterior to right), and posterior views of carapace 

with poorly preserved right valve and missing left valve, approx. X80. Figured specimen, USNM 

389812. Ladinian, USGS colln. 33131. 

14-17. Pseudobythocypris? sp. Dorsal (anterior to right), right, left, and posterior views of carapace, approx. 

X60. The white spot and line near the ventroposterior of fig. 16 is an artifact due to adhering lint. 

Figured specimen, USNM 389813. Carnian, USGS colln. 33141. 

18, 19. Hiatobairdia? sp. ex gr. H. arcuata Kristan-Tollman, 1970. Dorsal (anterior to left) and left, slightly 

tilted towards venter, views of abraded carapace, approx. X120. Figured specimen, USNM 389814. 

Norian, USGS colln. 33148. 

20-26. Covracythere gryci n. sp. Posterior oblique, dorsal (anterior to right), detail of right adductor muscleattachment scar, right, left, left tilted to show costae, and detail of left adductor muscle-attachment scar, 

approx. XlOO; details of adductor muscle-attachment scar approx. X400. Paratype, USNM 389817. 

Ladinian, USGS colin. 33129. 
U.S. GEOLOGICAL SURVEY BULLETIN 1664- C PLATE 2 

RECYTELLA, PSEUDOBYTHOCYPRIS?, HIATOBAIRDIA?, AND COVRACYTHERE 
PLATE 3 

FIGURES 1--6. Cornutobairdia reidae Sohn, n. sp. 

1-3. Dorsal (anterior to right), left, and right views of carapace, approx. X60. Holotype, CGS 

80063. Norian, Lewes River Formation, Yukon Territory, USGS colln. 33170. 

4. Inside view of right valve showing reversal of overlap and symmetry, approx. X60. Paratype, 

CGS 80064. Same colln. as above. 

5. Inside view of left valve showing reversal of overlap and symmetry, approx. X60. Paratype, 

CGS 80065. Same colln. as above. 

6. Left view of carapace with broken subcentral node, approx. X60. Paratype, CGS 80066. Same 

colln. as above. 

7. Ogmoconcha? sp. aff. H. limbata (Reuss, 1868) sensu Urlichs, 1971. Outside view of left valve on 

matrix, approx. X60. Figured specimen, USNM 389837. Ladinian, USGS colln. 33129. 

8-21. Cavussurella grammi Sohn, n. sp. 

8, 9. Outside and ventral (anterior to right) views of right valve, male, approx. X80. Paratype, USNM 

389838. Ladinian, USGS colin. 33124. 

10, 11. Dorsal oblique (anterior to left)andoutsideviewsofrightvalve,approx.XIOO. Paratype, USNM 

389839. Ladinian, USGS colin. 33132. 

12, 13. Dorsal (anterior to left) and outside views of right valve, anterior part of shell missing, 

approx. X80. Paratype, USNM 389840. Ladinian, USGS coHn. 33132. 

14--17. Outside, ventral (anterior to right), posterior, and detail ofventroposterior showing overlap of 

right valve, young growth stage on matrix, posterior part of shell missing, approx. X120; 

fig . 17, approx. X600. Paratype, USNM 389841. Ladinian, USGS coHn. 33121. 

18-21. Dorsal (anterior to right), right, left, and ventral (anterior toleft) views of steinkem with dorsal part of right valve retained, young growth stage, approx. X80. Note poorly preserved 

adductor muscle scar on fig. 20. Paratype, USNM 389842. Ladinian, USGS colln. 33132. 
U.S. GEOLOGICAL SURVE Y BULLETIN 1664-C PLATE 3 

CORNUTOBAIRDIA, OGMOCONCHA?, AND CAVUSSURELLA 
PLATE 4 

FIGURES 1-21. Cavussurella grammi Sohn, n. sp. 

1-5. Dorsal (anterior to right), left (slightly tilted), ventral (anterior to left), and posterior views of 

carapace with part of the ventroposterior missing, young growth stage, approx. X120. 

Paratype, USNM 389843. Ladinian, USGS colln. 33119. 

6-9. Inside, posterior, outside, and ventral (anterior to right) views of right valve of larger growth 

stage, approx. X80. Paratype, USNM 389844. Same colln. as above. 

10-15. Posterior, right, ventral (anterior to right), left, carapace of female, appox. X80; fig. 15, 

approx. X400. Holotype, USNM 389845. Same colln. as above. 

16- 21. Dorsal (anterior to right), right, anterior, left, ventral (anterior to left), and detail of shell 

(venter to left) at anteroventral of right valve of damaged carapace, approx. X80; fig. 21, 

approx. X400. Paratype, USNM 389854. Norian, USGS colln. 33169. 
U.S. GEOLOGICAL SURVEY BULLETIN 1664 - C PLATE 4 

CAVUSSURELLA 
PLATE 5 

FIGURES 1- 10. Ogmoconcha unicerata Sohn, n. sp. 

1- 7. Detail of posterior part of hinge, approx. X275; dorsal (anterior to left), outside, and posterior 

views of right valve, approx . X120, and detail of posteroventral spine, approx. X533. 

Holotype, USNM 389855. Ladinian, USGS colln. 33112. 

8- 10. Posterior, right, and dorsal views of carapace, approx. X120. Arrow on fig. 8 shows posterodorsal spine. Paratype, USNM 389856. Ladinian, same colln. as above. 

11- 16. Ogmoconcha aff. sp. 0 .owthropensis(Anderson, 1964). Posterior, dorsal (anteriortoleft), anterior, right, 

and left views of carapace with posterior two-thirds of right valve missing to expose adductor 

muscle-attachment scar, approx. X120; detail adductor muscle-attachment scar, approx. X360. Figured specimen, USNM 389857. Ladinian, USGS colln. 33154. 

17- 22. Ogmoconcha tailleuri n. sp. Outside, posterior, dorsal (anterior to left), and inside views of right valve, 

approx. X120; details of anterior and posterior parts of hinge, approx. X240. Paratype, USNM 

389858. Norian, USGS colin. 33155. 

23- 28 . Ogmoconchaalaskaense n. sp. Dorsal (anterior to right), right, posterior oblique detail of expose}~ part 

of right hinge, left, posterior, and exposed right hinge of carapace with posterior part of left valve 

missing, approx. X120; fig. 25, approx. X500; fig. 28, approx. X340. Note rough outside surface of 

shell, presumed to be surface deposit chartacteristic of many of the smooth forms at this locality, 

shown best on figs. 25, 28. Paratype , USNM 389859. Norian, USGS colin. 33158. 
U.S. GEOLOGICAL SURVEY BULLETIN 1664-C PLATE 5 

OGMOCONCHA 
PLATE 6 

FIGURES 1-9. Ogmoconcha sp. aff. 0. owthropensis (Anderson, 1964). 

1-3. Dorsal (anterior to right), right, and ventral (anterior to right) views of carapace, approx. 

Xl20. Figured specimen, USNM 389852. Norian, USGS colln. 33156. 

4, 5. Dorsal (anterior to left) and right views of steinkem of carapace with poorly preserved 

adductor muscle-attachment scar, approx. X120. Figured specimen, USNM 389860. Norian, USGS colln. 33159. 

6-9. Left, posterior, dorsal (anterior to right), and right views of carapace, approx. Xl20. Figured 

specimen, USNM 389861. Norian, USGS colln. 33169. 

10-18. Ogmoconcha tailleuri n. sp 

10-14. Dorsal (anterior to right), right and detail of left hinge to show denticulation, ventral (anterior 

to right), left, and posterior views of a left valve with a right valve of an other individual 

inside, approx. Xl20; detail of hinge, approx. X240. Paratype, USNM 389862. Norian, 

USGS colln. 33156. 

15-18. Left, dorsal (anterior to right) and detail of dorsal slightly tilted to show poorly preserved 

denticulated hinge, posterior, and right views of carapace, approx. XlOO; detail, app~ox. 

X200. Paratype, USNM 389863. Norian, USGS colln. 33165. 
U.S. GEOLOGICAL SURVEY BULLETIN 1664 -C PLATE 6 

OGMOCONCHA 
PLATE 7 

FIGURES 1-3. Covracythere binoda Sohn, n. sp. 

Dorsal (anterior to left), outside, and ventral (anterior to right) views of left valve, approx. X120. 

Holotype, USNM 389818. Ladinian, USGS colin. 33111. 

4-15. Dettermania truncata Sohn, n. sp. 

4-6. Dorsal (anterior to right), left, and ventral (anterior to left) views of steinkem with ventral 

two-thirds of left valve preserved to expose the thickness of the valve, approx. X60. 

Paratype, USNM 389819. Ladinian, USGS colin. 33112. 

7-11 . Ventral (anterior to left), anterior, dorsal (anterior to right), right, and left views of carapace 

with missing posterior, approx. X80. Ho1otype, USNM 389820. Same colin. as above. 

12-15. Left, ventral (anterior to right), dorsal (anterior to left), and right views of carapace, approx . 

X60. Paratype, USNM 389821. Same colin. as above. 

16-25 . Corvacythere gryci n. sp. 

16-20. Dorsal (anterior to left), left, posterior, right, and ventral (anterior to right) views of tecnomorph, carapace with only the innermost surface of the valves preserved, approx. XIOO. 

Paratype, USNM 389822. Norian, USGS colin. 33169. 

21, 22. Left (ventral up) and ventral views of poorly preserved steinkem of heteromorph, approx. 

X80. Paratype USNM 389823. Ladinian, USGS colin. 33113. 

23-25. Dorsal (anterior to right), left, and ventral (anterior to right) views of steinkem of heteromorph, approx. X53. Holotype, USNM 389824. Ladinian, USGS colin. 33111. 
U.S. GEOLOGICAL SURVEY BULLETIN 1664-C PLATE 7 

3 

18 / 

20 

COVRACYTHERE AND DETTERMANIA 
PLATE 8 

FIGURES 1- 6, 10-19. Ogmoconcha tailleuri n. sp. 

1- 3. Posterior, right, and dorsal (anterior to left) views of carapace, approx. X80. Paratype, 

USNM 389875. Ladinian, USGS colln. 33119. 

4--6. Posterior, right, and dorsal (anterior to right) views of carapace, approx . XIOO. 

Paratype, USNM 389876. Ladinian, USGS colln. 333124. 

10, 11. Dorsal (anterior to left) and posterior views of carapace, approx. X 120. Para type, 

USNM 389864. Ladinian, USGS colln. 33117. 

12- 14. Posterior, dorsal (anterior to right), and left views of carapace with a fragment of 

posterior of left valve missing to expose thickness of shell, approx. X120. Holotype, 

USNM 389865. Ladinian, USGS colln. 33119. 

15- 19. Dorsal (anterior to left), posterior, right, and left views of carapace with part of the 

ventral valve missing, approx. X80; detail of adductor muscle scar, approx. X400. 

Paratype, USNM 389866. Same colln. as above. 

7-9, 20- 27. Ogmoconcha sp. aff. 0. owthropensis (Anderson, 1964). 

7-9. Right, dorsal (anterior to left), and posterior views of carapace, approx. X80. Figured 

specimen, USNM 389877. Ladinian, USGS colln. 33109. 

20, 21. Dorsal oblique (anterior to right), and right views of carapace, approx. X80. Figured 

specimen, USNM 389878. Ladinian, USGS colln. 33130. 

22, 23. Dorsal (anterior to left) and right views of carapace, approx. X120. Figured specimen, 

USNM 389879. Norian, USGS colln. 33148. 

24, 25. Right view of carapace with most of the valve missing to expose the adductor muscleattachment scar, approx. X127, and detail of adductor muscle-attachment scar, 

approx. X433. Figured specimen, USNM 389880. Norian, USGS colln. 33145. 

26, 27. Dorsal (anterior to left) and right views of carapace, approx . X127 . Figured specimen, 

USNM 389881. Norian, USGS colln. 33149. 
U.S. GEOLOGICAL SURVEY BULLETIN 1664-C PLATE 8 

OGMOCONCHA 
FIGURES 

PLATE 9 

l- 4. Ogmoconcha tailleuri n. sp. Ventral (anterior to left), left, posterior, and right views of corroded 

carapace, approx. X80. Paratype USNM 389883. Ladinian, USGS colin. 31127. 

5-8. Ogmoconcha marquardti n. sp. Left, dorsal (anterior to left), posterior, and right views of 

steinkem, very young instar, approx. X120. Paratype, USNM 389882. Norian, USGS colin. 

33147. 

9-16, 19- 23. Ogmoconcha sp. aff. 0. owthropensis (Anderson, 1964). 

9- 12. Outside, ventral (anterior to left), and inside views of left valve, approx. X133; detail 

of anterior part of denticulated hinge, shown by arrow on fig. 11, approx. X820. 

Figured specimen, USNM 389919. Norian, USGS colin. 33156. 

13- 16. Dorsal (anterior to left), posterior, right, and ventral (anterior to right) views of 

carapace, approx. X120. Figured specimen, USNM 389884. Ladinian, USGS colin. 

33119. 

19-23. Dorsal (anterior to right), right, and anterior views of steinkem, approx. X120; details 

of right and left adductor muscle-attachment scar, approx. X600. Figured specimen, 

USNM 389886. Ladinian, USGS colin. 33130. 

17, 18, 24, 25. Ogmoconcha alaskaense n. sp. 

17, 18. Dorsal (anterior to left) and right views of carapace, posterodorsal part of right valve 

missing, approx. X120. Paratype, USNM 389885. Norian, USGS colin. 33148. 

24, 25. Right view of carapace with most of the valve missing to expose the adductor muscleattachment scar, approx. X 127, and detail of adductor muscle-attachment scar, 

approx. X433. Ho1otype, USNM 389887. Norian, USGS colln. 33149. 
U.S. GEOLOGICAL SURVEY BULLETIN 1664- C PLATE 9 

OGMOCONCHA 
PLATE 10 

FIGURES 1-8, 15-22. Ogmoconcha tailleuri n. sp. 

1- 4. Dorsal (anterior to left), posterior, right, and ventral (anterior to right) views of 

carapace, approx. X80. Paratype, USNM 389901. Ladinian, USGS colln,. 33119. 

5- 7. Left showing poorly preserved adductor muscle scar, posterior, and dorsal (anterior to 

left) views of steinkem, approx. X80. Note poorly preserved denticulation on 

dorsoposterior of fig. 7. Paratype, USNM 389899. Ladinian, USGS colln. 33111. 

8. Inside view of right valve showing denticulated hinge, approx. X120. Paratype USNM 

389888. Norian, USGS colln. 33155. 

15-19. Dorsal (anterior to right), posterior, right, left, and detail of adductor muscle scar 

exposed on left valve of carapace, approx. X120; detail, approx. X290. Paratype, 

USNM 389910. Ladinian, USGS colln. 33120. 

20- 22. Posterior, dorsal oblique tilted on right valve, and right views of carapace, approx. 

X120. Paratype, USNM 389911. Ladinian, USGS colln. 33129. 

9. Cavussurella? sp. 1. Posterior oblique view of fragment of left valve showing hinge groove and 

groove along venter for reception of smaller valve, approx. X80. Left end of micrograph 

trimmed to fit plate, compare with pl. 4, figs. 15, 21. Figured specimen, USNM 389851. 

Ladinian, USGS colln. 33117. 

10, 11. Rhombocythere? sp. Outside and inside views of fragment of left valve showing groove along the 

venter, approx. XlOO. Apparent denticulations on both ends of ridge above groove are probably 

artifacts due to preservation. Figured specimen, USNM 389853. Ladinian, USGS colln. 33132. 

12-14. Ogmoconcha sp. Dorsal (anterior to left), detail of dorsum to show denticulation, and right views 

of carapace with the right valve slightly rotated within the left to show denticulation hinge, 

approx. X80; detail, approx. X160. Figured specimen, USNM 389999. Lower Carnian, Hungary, USGS colln. 33172. 

23-32. Ogmoconcha marquardti n. sp. 

23- 26. Dorsal (anterior to left), right, and ventral (anterior to right) views of carapace on 

which dorsoposterior edge of right valve is missing to expose denticulated hinge, 

approx. X120; detail of exposed denticulation, approx. X600. Paratype, USNM 

389889. Norian, USGS colln. 33154. 

27-32. Posterior, right tilted down to show dorsal overlap, right tilted up to show ventral 

overlap, dorsal (anterior to right), left, and ventral (anterior to left) views of carapace. Holotype, USNM 389905. Norian, USGS colln. 33158. 
U.S. GEOLOGICAL SURVEY BULLETIN 1664-C PLATE 10 

OGMOCONCHA, CAVUSSURELLA?, AND RHOMBOCYTHERE? 
FIGURES 

PLATE 11 

1- 4. Triassocypris? sp. Dorsal (anterior to right), left, ventral (anterior to left), and posterior views of 

carapace, approx. X80. Figured specimen, USNM 390005. Norian, USGS colln. 33149. 

5, 6. Gen. and sp. indet. Right and ventral views of carapace, approx. X125. Figured specimen, 

USNM 390006. Norian, same colln. as above. 

7-12. Ogmoconcha tailleuri n. sp. 

7-9. Posterior, right, and ventral (anterior to right) views of right valve, approx. X55. The 

particle in the posteroventral area is not a spine. Paratype, USNM 389903. Ladinian, 

USGS colln. 33112. 

10. Right view of steinkem, approx . X120. Paratype, USNM 390004. Norian, USGS 

colln. 33152. 

11 . Right view of carapace, approx. X120. Holotype, USNM 389865, same specimen as 

pl. 8, figs. 12- 14. Ladinian, USGS colln. 33119. 

12. Ventral (anterior to right) view of carapace, approx. X80. Paratype, USNM 389875, 

same specimen as pl. 8, figs. 1-3. Ladinian, USGS colln. 33119. 

13-16, 20- 24. Ogmoconcha sp. 

13- 16. Outside, detail of denticulate hinge, detail of dorsal, and inside views of left valve, 

approx . X100; fig. 14, approx. X500; fig. 15, approx. X200. Figured specimen, 

USNM 390009. Carnian, Hungary, USGS colln. 33172. 

20, 21. Inside view of right valve converted to fluorite, approx. X100; detail of posterior part 

of denticulate hinge, approx. X300. Compare with figs. 14, 15, 18, 19. Figured 

specimen, USNM 390007. Carnian, Hungary, USGS colln. 33172. 

22-24. Inside view of right valve treated with hydrogen peroxide, converted to fluorite with 

hydrofluoric acid, and then treated with ultrasonic waves to clean and break the 

carapace. Fragment of left valve, approx. X80; right view of carapace before treatment, approx. X40. Figured specimen, USNM 390008. Carnian, Hungary, USGS 

colln. 33172. 

17-19. Ogmoconcha alaskaense n. sp. Dorsal (anterior to right), approx. X130; detail of denticulate 

hinge, approx. X250; inside of left valve, approx. X125. Paratype, USNM 389896. Norian, 

USGS colln. 33148. 

25 , 26 . Cavussurella? sp. I. Outside and inside views of fragment of left valve, approx. X80. Note dorsal 

pleat on fig. 25, and hinge and ventral grooves on fig. 26. Figured specimen, USNM 389851, 

same specimen as pl. 10, fig. 9. Ladinian, USGS colln. 33117. 

27. Cavussurella? sp. 2. Outside view of steinkem of left valve on matrix, approx . X60. Figured 

specimen, USNM 39003. Ladinian, USGS colln. 33129. 

28-31. Rhombocythere? sp. 

28, 31. Dorsal and ventral views of fragment of left valve, approx. X100. Figured specimen, 

USNM 389853, same specimen as pl. 10, figs. 10, 11. Ladinian, USGS colin. 

33132. 

29, 30. Dorsal and outside views of right valve, possibly a steinkem, approx. X100. Figured 

specimen, USNM 389912. Ladinian, USGS colln. 33132. 
U.S. GEOLOGICAL SURVEY 

/~·- ~- "'\ 

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BULLETIN 1664-C PLATE 11 

TRIASSOCYPRIS?, OGMOCONCHA, CAVUSSURELLA?, AND RHOMBOCYTHERE?