bluuebunny/crossref_metadata_2025 huggingface dataset:
Rutichnus: a new ichnogenus for branched, walled, meniscate trace fossils
Authors: D'Alessandro Assunta , Bromley Richard G. , Stemmerik Lars
Published: August 2016

Two forms of branched, thickly walled, meniscate trace fossils occur in the Permian of East Greenland and Miocene of southern Italy. A new ichnogenus,Rutichnus, is erected for these specimens, and its possible synonyms and mode of formation are discussed. The two ichnospecies,R. irregularis(D'Alessandro) andR. rutisn. ichnosp., differ in the manner of branching and external rugosity.
Ultrastructure in cuticle fromHoploparia stokesi(Decapoda: Nephropidae) from the Lopez de Bertodano Formation (Late Cretaceous–Paleocene) of Seymour Island, Antarctica
Authors: Feldmann Rodney M. , Tshudy Dale
Published: August 2016

Examination, utilizing scanning electron microscopy, of 58 specimens ofHoploparia stokesi(Weller) from the Maastrichtian portion of the Lopez de Bertodano Formation, Seymour Island, Antarctica, leads to the conclusion that cuticular ultrastructure may be used to distinguish molted from deceased remains of nephropid lobsters. Molted cuticle is characterized by deterioration, or loss, of lamination in the inner endocuticle whereas cuticle, during the intermolt phase, exhibits lamination throughout the endocuticle as well as the exocuticle. Diagenetic effects may obscure lamination throughout the cuticle. These observations confirm that Salter's position is typical of molted remains in fossils. Furthermore, partial remains ofH. stokesigenerally are molts. Preservational quality of molted remains tends to be better than that of corpses.
Changes in Permian marine ostracode faunas during regression, Florena Shale, northeastern Kansas
Authors: Costanzo Gary V. , Kaesler Roger L.
Published: August 2016

The Florena Shale (Permian, Wolfcampian) of the Midcontinent of North America was deposited in a restricted marine basin. Shifting environments due to marine regression caused a gradual change in the ostracode fauna. Cluster analysis and ordination by nonmetric multidimensional scaling of data on ostracode relative abundances revealed three ostracode assemblages, each characteristic of a different environment. TheCryptobairdia seminalisassemblage from the lowest Florena Shale is characteristic of deeper water, offshore, marine environments with only minor influx of terrigenous mud. TheAmphissites centronotusassemblage found above theC. seminalisassemblage occupied a similar environment, but with greater influx of terrigenous mud and intervals of increased turbidity. TheKnightina texanaassemblage occurs stratigraphically highest and probably represents a quiet-water, very shallow, nearshore, marine environment. Although protected from strong wave and current activity, the water mass was occasionally turbid.

Species diversity of ostracodes is high both at the base of the Florena Shale, which was deposited in the most offshore position, and again at the top of the lower part of the Florena Shale, which was deposited nearer to the shore. In contrast to diversities of assemblages of ostracodes from similar environments in other stratigraphic units, theK. texanaassemblage has an anomalously high diversity. This is due in part to time averaging of adjacent ostracode assemblages and a strong taphonomic overprint.
Mandalacystis, a new rhipidocystid eocrinoid from the Whiterockian Stage (Ordovician) in Oklahoma and Nevada
Authors: Lewis Ronald D. , Sprinkle James , Bailey J. Bowman , Moffit John , Parsley Ronald L.
Published: August 2016

Mandalacystis dockeryi n. gen. and sp. is known from seven complete or nearly complete thecae, six partial thecae, and numerous separate plates from the Oil Creek Formation in south-central Oklahoma, and a single thecal plate from the Antelope Valley Limestone in Nevada. Details of skeletal microstructure (stereom) are well preserved, permitting scanning electron microscopy for the first time in the Eocrinoidea, and demonstrating that plate thickness on thecal faces is only 60–70 μm. Mandalacystis is characterized by labyrinthine ridges on both faces of the theca, relatively short brachioles, and a normal stem with holdfast (at least in juvenile stages). Based on the normal biserial arrangement of brachiolar plates in the brachioles and the possession of a normal stem, Mandalacystis appears to be one of the most primitive rhipidocystids, closely related to Petalocystites.

Mandalacystis dockeryi lived in a storm-dominated, shallow-water offshore habitat on patches of skeletal debris surrounded by soft, terrigenous mud. This setting may have been conducive to the transition from an erect, attached mode of life to the prone, unattached lifestyle of later rhipidocystids.
Dinosaur gastroliths revisited
Authors: Stokes Wm. Lee
Published: August 2016

Additional information on the alleged gastroliths in Early Cretaceous formations of the Western Interior has changed the writer's opinion from skepticism about a dinosaur causative agency to belief that it is a valid explanation. Concentrations of exotic rounded and polished stones have been found in close association with a number of skeletons. Aside from this, the best evidence is distribution of individual stones in environments where inorganic agencies seem improbable; distinctive individual stones have apparently been carried hundreds of kilometers. Gastroliths have value as quasi-guide fossils. From geographic and geologic associations it is suggested that various sauropods and perhaps the contemporary ornithopod, Tenontosaurus tilleti, were the chief stoneswallowers of the Early Cretaceous of the Western Interior.
Psilonichnus (Fürsich) in late Pliocene subtidal marine sands of eastern England
Authors: Humphreys Bernard , Balson Peter S.
Published: August 2016

Large trace fossils attributed to the ichnogenus Psilonichnus (Fürsich) have been identified in subtidal sediments of the Red Crag Formation (late Pliocene) of Walton-on-the-Naze, Essex, U.K. The traces are vertical or inclined, tapering cylindrical structures, occasionally branched, up to 2.3 m long. The structures are mud-rich relative to the surrounding sediment and their fills often show a spiralling grain fabric. The ichnogenus Psilonichnus has formerly been attributed to the burrowing activities of intertidal and supratidal crab species. The known fossil crab assemblage of the Red Crag contains no deep burrowing species. The traces are thus attributed to other crustaceans, possibly thalassinidean shrimps. The occurrence indicates that Psilonichnus may have a greater palaeoenvironmental range than previously realized.
Lidaconus palmettoensisn. gen. and sp.: an enigmatic Early Cambrian fossil from western Nevada
Authors: Onken Beth R. , Signor Philip W.
Published: August 2016

Lidaconus palmettoensisn. gen. and sp. is a recently discovered fossil from the Lower Cambrian Harkless Formation (Bonnia–OlenellusZone) in Esmeralda County, Nevada. The conoidal fossils were originally calcareous and have been replaced by silica. The cones are distinctive in their consistent morphology, the presence of weak annulations, and the lack of any internal structures such as septa, tabulae, or dissepiments. Because of the paucity of diagnostic characters due to the simple morphology and the lack of original microstructure, taxonomic affinities are uncertain.
Ramseyocrinus (Crinoidea) from the Arenig of Morocco
Authors: Donovan Stephen K. , Savill Jeremy J.
Published: August 2016

The discovery of the arms of the disparid inadunate crinoid Ramseyocrinus Bates from the Arenig (Lower Ordovician) of Morocco extends the geographic range of this genus, previously only known from south Wales, United Kingdom, and the Montagne Noire, France. It is probable that the Moroccan specimen represents a new species. This is the first Lower Ordovician crinoid to be described from Africa.
Crinoids from the Brassfield Formation of Adams County, Ohio
Authors: Ausich William I. , Dravage Philip
Published: August 2016

A new species of Ptychocrinus, Ptychocrinus adamsensis, and dendrocrinid, genus and species undetermined, are described from the Lower Silurian (Llandovery) Brassfield Formation of Adams County, Ohio. Unlike previously recognized Ptychocrinus species, P. adamsensis has biserial arms. Accordingly, the generic concept of Ptychocrinus is broadened. Ptychocrinus adamsensis is the youngest North American species of Ptychocrinus. Ptychocrinus is not known from the Brassfield fauna that has been previously described from the Greene–Montgomery County area of Ohio.
Late Cretaceous fish from the Blufftown Formation (Campanian) in western Georgia
Authors: Case Gerard R. , Schwimmer David R.
Published: August 2016

A Campanian fish assemblage is described from the uppermost Blufftown Formation in western Georgia. Fifteen chondrichthyan and eight osteichthyan taxa are identified, virtually all for the first time from the region. The study area represented a transitional zone between the Atlantic and eastern Gulf of Mexico Coastal Plain Provinces during the Late Cretaceous, and shows faunal relationships with both.
Stress fracture in a ceratopsian phalanx
Authors: Rothschild Bruce M.
Published: August 2016

A prominent anterior bulge on a ceratopsian dinosaur phalanx was examined for evidence of infection or stress (fatigue) fracture. The presence of a knife-slice type radiolucency, associated with periosteal reaction, was pathognomonic (diagnostic) for a stress fracture. Stress fractures have previously been recognized only in humans, racing greyhounds, and horses.
Sodium metatungstate: a new heavy-mineral separation medium for the extraction of conodonts from insoluble residues
Authors: Krukowski Stanley T.
Published: August 2016

Sodium metatungstate (SMT), 3Na2WO4 · 9WO3 · H2O, is a nontoxic (Sax, 1979), high-density (1.00-3.10 g/cm3) separating compound which results in nearly neutral (pH 6) solutions of relatively low viscosity. It was presented as a medium for density gradient centrifugation by Plewinsky and Kamp (1984). Since then, investigators have used SMT (or sodium polytungstate) as a high-density medium for routine mineral separations, for recovery of conodonts from insoluble residues, for separation of various feldspar species from one another, and for segregation of inorganic mineral fractions (ash) from coal.
New Carboniferous species of Hippocardia (Rostroconchia, Mollusca) from the Midcontinent, USA
Authors: Hoare R. D. , Steinker P. J. , Mapes R. H.
Published: August 2016

Three new species of Hippocardia, H. ancora, H. pala, and H. cucullata, are described. Hippocardia ancora and H. pala occur together in the Lazy Bend Formation (Desmoinesian) of Texas. Hippocardia cucullata occurs in the Imo Formation (Chesterian) of Arkansas.
New species of Nematothallus from the Silurian Bloomsburg Formation of Pennsylvania
Authors: Strother Paul K.
Published: August 2016

The early terrestrial fossil record contains numerous Siluro-Devonian problematic Thallophyta which have morphological and habitat characteristics intermediate between the algae and the embryophytic plant kingdom. Three new species of the genus Nematothallus Lang (N. taenia, N. lobata, and N. elliptica) are described from a coaly lens in the Bloomsburg Formation (Ludlow). They are included in the order Nematophytales, which is placed in a new informal taxonomic group, Paraphyta, intended to include enigmatic, terrestrial plant-like fossils. These species designations are based upon the gross morphology of carbonized thalli which consist of an underlying anatomy of flattened tubular elements. The association and attachment of cuticles and axes of ?Prototaxites to Nematothallus is clearly demonstrated in these collections. The morphological and anatomical variety expressed in the numerous fragments of thalli from the deposit implies moderate levels of organic diversity in a “flora” of nonvascular, terrestrial plant-like thallophytes which predates the adaptive radiation of the embryophytes.
Cretaceous brachiopods from James Ross Island, Antarctic Peninsula, and their paleobiogeographic affinities
Authors: Sandy Michael R.
Published: August 2016

Articulate brachiopods from the Aptian–Coniacian (Kotick Point and Whisky Bay Formations, Gustav Group) and the Santonian–Campanian (Santa Marta Formation, Marambio Group) of James Ross Island are described. A new terebratulid species,Rectithyris whiskyin. sp., is described from the late Albian–early Coniacian of the Whisky Bay Formation. The record from the late Albian is supported by palynological evidence making it contemporaneous with other species ofRectithyrisfrom Europe. The relative abundance ofRectithyris whiskyin. sp. in late Turonian to early Coniacian sections indicates an extended biohorizon that may aid biostratigraphic correlation in the James Ross Island region.

The brachiopods have some affinities with faunas described from Europe, northern Siberia, North America, Madagascar, southern India, Western Australia, and Alexander Island, Antarctic Peninsula. Elements of the James Ross Island brachiopod fauna probably migrated by the following routes: 1) from northern high latitudes via the Eastern Pacific; 2) from Europe via the north and central Atlantic and opening south Atlantic Ocean; and 3) via Eastern Tethys, the East African Seaway, to the south Atlantic Ocean. Brachiopod evidence supports a fully marine connection between the central Atlantic and south Atlantic Ocean (Route 2) possibly as early as the late Albian (as do ammonite faunas from western Africa), and certainly by the late Turonian. Route 3 was established in the Cretaceous by the Aptian?–Albian to eastern Africa and Madagascar and to the Antarctic Peninsula by the late Turonian. Faunal links between James Ross Island and Western Australia support the Late Cretaceous juxtaposition of these plates.

A distinct austral brachiopod fauna may be present in the Cretaceous from the Aptian onwards (although current evidence is scant). Antarctic Peninsular and Western Australian faunas yield five brachiopod genera (and their species) endemic to Gondwanaland's southern marine fauna. Other genera known from the Antarctic Peninsula (Kingena, Ptilorhynchia, andRectithyris) and the Northern Hemisphere may have species endemic to Gondwanaland.
New Late Eocene mollusks from localized limestone deposits formed by subduction-related methane seeps, southwestern Washington
Authors: Squires Richard L. , Goedert James L.
Published: August 2016

The trochid archaeogastropodMargarites(Pupillaria)columbianan. sp., the mytilid bivalveModiolus(Modiolus)willapaensisn. sp., and the vesicomyid bivalveCalyptogena chinookensisn. sp. are described from the earliest known fossil communities associated with subduction-related methane seeps. The communities are in very localized limestones of late middle to late Eocene age along the southwestern margin of Washington. These limestones contain large numbers of chemosynthetic bivalves and worm tubes, as well as other macrobenthos, that colonized around cool-temperature methane seeps along the landward slopes of an ancient subduction-zone complex.

Calyptogena chinookensisn. sp.is the earliest known species of this genus, which was previously known from Miocene to Recent.
Size-related evolutionary patterns among species and subgenera in the Strombina group (Gastropoda: Columbellidae)
Authors: Budd Ann F. , Johnson Kenneth G.
Published: August 2016

This study represents a preliminary analysis of variation in size and shape in a large and diverse molluscan clade, the Strombina group, over the past 20 million years. Restored height and width were measured on 5,099 individuals of 72 species and 5 genera. Size was estimated by adding height and width, and shape was estimated by dividing height by width. Patterns of variation were analyzed quantitatively among species, subgenera, and genera using univariate statistical tests comparing means and variances and linear regression.

Results of univariate tests show that both shape and size vary among species within subgenera (the specific level) and among genera (the generic level). However, only shape varies among subgenera within genera (the subgeneric level). Regression analyses for each species show that the relationship between height and width is linear, indicating that growth is never allometric with respect to these characters. Because of this nonallometric growth, rates of shape relative to size change can never vary, imposing a severe constraint on shape change and, in turn, shape evolution. Regression models for species within subgenera have equal slopes but differ slightly in intercept. Subgeneric models differ more in intercept. Generic level models differ in slope. These results suggest that formation of species within subgenera primarily involves extension or contraction of trajectories between height and width within species (=static vectors), resulting in size change without shape change. Shape change is more important in the evolution of higher categories.

To examine overall morphologic change in the clade through time, mean sizes and shapes of species were analyzed using nonparametric statistics. Only a slight tendency exists within the clade for increase in species size, and this tendency is best expressed within two species-rich subgenera having long stratigraphic ranges. No directional trends exist for change in species shape. No relationship is found between species size and probability of speciation or extinction, or between species size and species duration, thus negating the role of species selection. Nevertheless, species are smaller in size in the northern Caribbean, a region characterized by extreme fluctuations in temperature. Larger species occurred only after a taxonomic radiation in the eastern Pacific, a more restricted region possibly characterized by reduced environmental disturbance. During this radiation, normal patterns of morphologic change associated with speciation appear to have been disrupted.
Late Osagean and Meramecian Actinocrinites (Echinodermata: Crinoidea) from the Mississippian stratotype region
Authors: Ausich William I. , Kammer Thomas W.
Published: August 2016

ActinocrinitesMiller from the Mississippian stratotype region of Illinois, Iowa, and Missouri are redescribed and redefined based upon study of the type material and morphometric analyses.Actinocrinites pernodosus, A. lowei, A. jugosus, A. gibsoni, andA. probolosn. sp. are recognized as valid species that occur in these strata. A combination of both metric and qualitative characters must be used to differentiate these species.Actinocrinitesis known from the Montrose Chert Member of the Keokuk Limestone, the Keokuk Limestone, and the lower part of the Warsaw Formation, all late Osagean, in the stratotype region. In addition,Actinocrinites pernodosusandA. loweiare reported from the early Meramecian upper part of the Warsaw Formation, which is the first Meramecian occurrence ofActinocrinitesin the stratotype region.Actinocrinites probolosn. sp. was ancestral toA. lowei, and the latter was probably ancestral toA. pernodosus.

Nomenclatural and systematic acts include the following: 1)Actinocrinites lowei(Hall, 1858) is the senior synonym ofActinocrinus brontesHall, 1860,Actinocrinites lobatus(Hall, 1860), andA. unicarinatus(Hall, 1860); 2)Actinocrinites jugosus(Hall, 1860) is the senior synonym ofA. augustatusMiller and Gurley, 1894; and 3) the concept applied incorrectly toA. lobatusby Wachsmuth and Springer (1897) represents a distinct species,Actinocrinites probolosn. sp.
Conodont biostratigraphy of the upper part of the Clinton Group and the Lockport Group (Silurian) in the Niagara Gorge region, New York and Ontario
Authors: Kleffner Mark A.
Published: August 2016

Twenty-nine conodont species are represented in formations comprising the upper part of the Clinton Group and the Lockport Group at four localities in Niagara County, New York, and adjacent Ontario, Canada. Four previously unrecognized species of Ozarkodina represented in two samples from the Oak Orchard Formation are described. Ozarkodina sagitta rhenana (Walliser) and O. sagitta sagitta (Walliser) appear to form an evolutionary lineage in which the latter evolved from the former during the late early Wenlockian by slight modification of the Pa element. Elements in the other corresponding positions in their respective apparatuses are virtually identical.

The Williamson Shale, Irondequoit Limestone, Rochester Shale, and DeCew Formation of the Clinton Group belong in the upper part of the Pterospathodus amorphognathoides to the middle part of the Ozarkodina sagitta sagitta Chronozone, and are early to early middle Wenlockian in age. The Gasport, Goat Island, Eramosa, and Oak Orchard Formations of the Lockport Group belong in the middle part of the O. sagitta sagitta to the lower part of the Ancoradella ploeckensis Chronozone, and are early middle to late Wenlockian in age.
First Clarkeia and Heterorthella (Brachiopoda; Lower Silurian) occurrence from the Paraná Basin in eastern Paraguay
Authors: Boucot A. J. , de Melo Jose Henrique G. , Santos Neto Eugenio V. , Wolff Sven
Published: August 2016

The existence of the Malvinokaffric Realm during the Silurian (Boucot, 1990) is based on the presence of three endemic brachiopod genera (Anabaia, Clarkeia, Heterorthella), and their absence in the coeval North Silurian Realm, where roughly 100 other brachiopod genera Aegiria to Zygospiraella are present. Within the Malvinokaffric Realm the vast reaches of the Paraná Basin, covering an area almost equivalent to the United States east of the Mississippi River, has previously yielded only Anabaia, and that from a single area. In light of this, the recognition of both Clarkeia and Heterorthella within the confines of the Paraná Basin is noteworthy.
A new Lower Ordovician species of Calathium, and skeletal structure of western Utah calathids
Authors: Church Stephen B.
Published: August 2016

Conical and vase-shaped calathids are found in the Lower Ordovician Fillmore Formation of western Utah associated with intraformational conglomerates and small patch reefs. Calathium yersini n. sp. exhibits patterns of both the inner and outer walls of calathid two-wall construction. The broadly annulate walls are constructed from meroms with fused proximal merom feet forming the inner wall. The reticulate-patterned outer wall is formed by interlocking stellate ribs at the distal end of each merom. Latitudinal (horizontal) ribs interlock adjacent merom ribs side by side at the tips of ribs while meridional (vertical) ribs overlap merom shaft to merom shaft. Inner and outer walls are perforate. Pore-canal casts preserved in silicified molds suggest an exit and entrance current circulation for inner and outer wall pores. Upper ends of the calathids are not preserved, but an open cup is interpreted from infill material and encrustation of the interior cup wall by epibionts. Epibionts commonly encrust and thicken Calathium outer walls, with the cyanobacterium Girvanella as the dominant encrusting organism. Calathium yersini n. sp., among the earliest of receptaculitids, has a morphology suitable for water circulation consistent with that of filter-feeding organisms.
A revision of Anostylostroma, Atelodictyon, and related genera (Paleozoic Stromatoporoidea)
Authors: Stearn Colin W.
Published: August 2016

Laminae of genera considered in this revision are sheets of planar, compact tissue (order Clathrodictyida) or a network formed by arms (colliculi) emerging from pillars (order Actinostromatida). Pillars, confined to a single interlaminar space, are simple rods, branch upwards, or have complex cross sections. The scope of Anostylostroma is limited to species with complexly upwardly branching pillars and simple planar laminae. Species with predominantly y- or v-shaped pillars are removed to Schistodictyon. Simplexodictyon is limited to species with double laminae formerly referred to Diplostroma. A new genus, Petrostroma (type species: Simplexodictyon simplex Nestor), is proposed for species with simple, planar laminae and rodlike pillars. The scope of Atelodictyon is restricted to species with planar, simple laminae resembling the type species and many species with laminae formed of colliculi previously placed in this genus are assigned to Aculatostroma. Other genera discussed include: Crumplestroma and Coenellostroma (both synonyms of Aculatostroma), Pseudoactinodictyon, Stelodictyon, Clathrodictyon, and Nexililamina and Coenostelodictyon (both synonyms of Schistodictyon).
Worthenopora: an unusual cryptostome (Bryozoa) that looks like a cheilostome
Authors: Hageman Steven J.
Published: August 2016

Worthenopora is a Mississippian cryptostome bryozoan genus with certain characteristics that so closely resemble those of some cheilostomes (Jurassic–Recent) that previous bryozoan experts speculated whether Worthenopora should be assigned to the order Cheilostomata. This raises the question of possible affinities between cryptostomes (class Stenolaemata) and cheilostomes (class Gymnolaemata). Based on wall structure, growth sequence, zooecial shape, and secondary structures such as stylets, Worthenopora is here shown to be a stenolaemate, assignable to the suborder Ptilodictyina with other bifoliate cryptostomes. Although the exterior appearance of Worthenopora superficially resembles some cheilostomes, it represents rather limited divergence from more typical bifoliate growth patterns. Additionally, presence of characteristics such as elongate zooecia with thin exozones, cuticular medial plane, and distinctive exterior ridges justifies retention of the monogeneric family Worthenoporidae. Three species (W. spatulata, W. spinosa, and W. valmeyerensis), known only from North America and primarily restricted to the Illinois Basin, are recognized. Analysis of apertural spacing in these species suggests a trade-off between feeding efficiency and occupation of water-column space. Worthenopora valmeyerensis is considered a hypermorphic derivative of W. spinosa.
First dinosaur record from Tennessee: a Campanian hadrosaur
Authors: Bryan Jonathan R. , Frederick Daniel L. , Schwimmer David R. , Siesser William G.
Published: August 2016

Recently, several dinosaur bones were rediscovered in the paleontological collections at the University of Tennessee, Knoxville, with a label indicating that the material was collected from the Cretaceous of west Tennessee. Since dinosaur remains have never been reported from Tennessee, this discovery prompted further investigation.
Upper Silurian heliolitine corals, Canadian Arctic: Taxonomic method, keys to identification, and biogeographic relationships
Authors: Dixon Owen A.
Published: August 2016

Taxonomy of heliolitine corals, and tabulate corals in general, benefits from analysis of larger assemblages of coralla that approximate populations. Quantitative data derived from such assemblages allow intraspecific variation to be tested rigorously and illustrated, and similar, co-occurring species to be discriminated using normal patterns of continuous population variation. Field collection and analysis necessarily involve recording and comparing assemblages from the full spectrum of sedimentary facies available at any one stratigraphic level and from the maximum available stratigraphic range. The large published taxonomic literature on heliolitine corals is a daunting obstacle to identification at the species level because a substantial part appears to involve taxonomic splitting to a degree inconsistent with variation known in modern coral species. The heliolitine corals studied occur in Ludlow-age ramp and shelf carbonate facies in the Boothia Uplift region in the southern Arctic archipelago of Canada. The “population” approach resulted in discrimination of 18 morphotaxonomic species, belonging to five genera and four families. A few select morphologic characters, incorporated in simple identification keys, are particularly helpful in distinguishing the 11 heliolitid and four stelliporellid species present, and are useful in screening the voluminous literature on species of Heliolites. Six of the species compare closely to Silurian species reported from central Kazakhstan, West Siberia, and North China; few are shared with other regions. The principal affinities are consistent with occurrence in the Uralian-Cordilleran paleogeographic region in the Silurian northern hemisphere. Eight species do not appear to be recorded in published literature elsewhere and are apparently endemic.
Skeletal microstructure, geochemistry, and organic remnants in Cretaceous scleractinian corals: Santonian Gosau Beds of Gosau, Austria
Authors: Sorauf James E.
Published: August 2016

Extremely well-preserved specimens of the species Rennensismilia complanata and Aulosmilia cuneiformis occur in Santonian (Upper Cretaceous) strata of the Lower Gosau beds, near Gosau, Austria. Two of these, here reported, have aragonitic skeletal mineralogy and skeletal structures that are typical for their families, and, in addition, show distribution of trace elements (Sr and Mg above all) that confirm the biogenic origin of structures observed. R. complanata also has proteinaceous matrix preserved within its skeleton, which, seen here for the first time in electron micrographs of living or fossil corals, forms sheaths of organic matrix surrounding bundles of skeletal crystallites. Matrix is most abundant along the axial plane of septa, which also is the first-formed part of each septum. Although A. cuneiformis lacks observable organic matrix materials, its skeletal structure and its distribution and amount of trace elements are analogous to that seen in R. complanata and also in modern corals.
Upper Middle Devonian (Givetian) gastropods from the Kersadiou Formation, Brittany, France
Authors: Blodgett Robert B. , Frýda Jiřá , Racheboeuf Patrick R.
Published: August 2016

Gastropods are described for the first time from the Kersadiou Formation (middle Givetian) in the vicinity of Brest, Brittany, northwestern France. Twenty-three species of gastropods are recognized. New taxa include the new genera,Calvibembexia, Kersadiella, Breizospira, Finisterella, Parahormotomina, andNodoloxonema, represented by the new speciesCalvibembexia lethiersi, Kersadiella babini, Breizospira crozonensis, Finisterella tibidiensis, Parahormotomina sibertae, andNodoloxonema plusquelleci.Further new species include:Sinuitina(Sinuitina)morzadeci, Crenistriella armoricana, Patellilabia(Phragmosphaera)ponceti, Angyomphalus(Eoangyomphalus)weyanti, Eoplatyzona ongaroae, Murchisonia oehlerti, andHormotomina fiacrensis.The biogeographic affinities of the fauna show a strikingly unusual admixture of Eastern Americas Realm taxa such asHormotominaandCrenistriella.This suggests that during the middle Givetian, the Massif Armoricain (northwestern France) represented an area of Realm-boundary mixing between the Old World and Eastern Americas Realms, while older Devonian gastropod faunas of the Massif Armoricain are wholly of Old World Realm type.
Protoreodon walshi, a new species of agriochoerid (Oreodonta, Artiodactyla, Mammalia) from the late Uintan of San Diego County, California
Authors: Theodor Jessica M.
Published: August 2016

A new agriochoerid,Protoreodon walshinew species, from the middle Eocene Santiago Formation, San Diego County, California, is described from the Jeff's Discovery and Rancho del Oro local faunas, considered to be late Uintan in age. It differs from most other species ofProtoreodonin having an undivided P4para-metacone and a P3protocone connected to the paracone by a buccolingual crest. Associated postcranial material is abundant and well preserved. The postcranial skeleton shows several features which probably represent the primitive oreodont condition, including closely appressed metapodials, hoofed ungual phalanges, the lunar in broad contact with both the magnum and the unciform in anterior view, and having the magnum larger than the trapezoid.

Two specimens of a larger morph,Protoreodoncf.walshi, show a different P3morphology and might represent another new species. Diversity of agriochoerid oreodonts in California is at least as high as has been reported for the Vieja Group of Texas, although not as high as in the Uinta Basin of Utah, where the genusDiplobunopsis also present.
A new subfamily of geomyoid rodents (Mammalia) and a possible origin of Geomyidae
Authors: Korth William W. , Chaney Dan S.
Published: August 2016

Two new species, Mojavemys galushai and Phelosaccomys neomexicanus, are described from the Barstovian of New Mexico. Both of these species are assigned to a new subfamily, the Mojavemyinae. It is uncertain as to whether this new subfamily should be referred to the Heteromyidae or Geomyidae.

Both Mojavemys an Phelosaccomys retain some heteromyid characteristics while developing advanced traits of geomyids. It is possible that these genera represent transitional forms between a heteromyid ancestor and advanced geomyines, thus deriving the Geomyidae directly from the Heteromyidae sometime in the middle Tertiary. It is also possible that the Mojavemyinae are a subfamily of heteromyids only convergent with geomyids. A third possiblity is that the mojavemyines are among a group of middle Tertiary geomyoids from which both Recent heteromyids and geomyids were derived.
A new ichnospecies ofNereitesfrom Carboniferous tidal-flat facies of eastern Kansas, USA: Implications for theNereites-Neonereitesdebate
Authors: Mangano M. Gabriela , Buatois Luis A. , Maples Christopher G. , West Ronald R.
Published: August 2016

Predominantly horizontal, gently curved to slightly sinuous traces constituting uniserial rows of imbricated, subspherical sediment pads occur in Pennsylvanian tidal-flat facies of eastern Kansas. These traces exhibit a complex, actively filled internal structure. The presence of a median tunnel enveloped by overlapping pads of reworked sediment indicates that these biogenic structures should be included in the ichnogenusNereitesMacLeay in Murchison, 1839. A new ichnospecies,N. imbricata, is erected. Externally,Nereites imbricatadiffers from the otherNereitesichnospecies by the large, tightly packed, imbricated pads that commonly result in an annulated appearance on bedding-planes. Internally, obliquely arranged, arcuate laminae envelope the median tunnel and tend to follow the outline of the external semispherical pads. Additionally, the behavioral pattern reflected byN. imbricatais less specialized than that of the otherNereitesichnospecies.Eione monoliformisTate, 1859 resemblesN. imbricatain general appearence, but lack the diagnosticNereitesinternal structure, and is invariably preserved as positive epireliefs. Occurrence ofNereites imbricataas both median tunnels surrounded by reworked sediment (Nereitespreservation) and uniserial rows of imbricated sediment pads (Neonereitespreservation) supports the notion thatNeonereitesSeilacher, 1960 is a preservational variant ofNereites.The ichnogenusNereitesis an eurybathic form and is a common component of Paleozoic shallow-marine facies.
Borealosuchus(Crocodylia) from the Paleocene of Big Bend National Park, Texas
Authors: Brochu Christopher A.
Published: August 2016

Fossil vertebrates have been described from the Paleocene of Big Bend National Park, Brewster County, Texas, by Wilson et al. (1952), Wilson (1967), Schiebout (1973, 1974), and Standhardt (1986). These studies focused on the mammalian component of the fauna, although crocodylian and chelonian remains are known. Schiebout (1973) referred a partial dentary toDiplocynodon.Teeth in the Black Peaks Formation were referred toAllognathosuchusby Straight (1996); Standardt (1986) discussed isolated crocodyliform teeth from across the Cretaceous-Tertiary Boundary in this area, but did not assign any of them to named taxa. Brochu (1996) briefly reviewed more complete remains, which were found to include an alligatorid and a member ofBorealosuchus.The giant crocodylianDeinosuchusand a goniopholidid are known from underlying Cretaceous sediments (Rowe et al., 1992), and overlying Eocene units are known to preserve remains of the ziphodont taxonPristichampsus(Busbey, 1986).
Jagtia kunradensis, a new genus and species of clawed lobster (Decapoda: Nephropidae) from the Upper Cretaceous (Upper Maastrichtian) Maastricht Formation, The Netherlands
Authors: Tshudy Dale , Sorhannus Ulf
Published: August 2016

A new genus and species of clawed lobster, Jagtia kunradensis, is described from the Upper Cretaceous (Upper Maastrichtian) Kunrade Limestone facies of the Maastricht Formation, The Netherlands. Three nephropid lobster genera and at least three species (Oncopareia bredai Bosquet, 1854, sensu Tshudy, 1993, Oncopareia sp. Tshudy, 1993, Hoploparia beyrichi Schlüter, 1862, and Jagtia kunradensis) have now been collected from limestones of the Maastrichtian type area (southeastern Netherlands and northeastern Belgium). Cladistic methods were employed in re-evaluating the phylogenetic relationships of the nephropid lobsters, including Jagtia. These analyses indicate that Jagtia is part of a clade that includes the recent Thymops and Thymopsis. The new genus is the first fossil form to be closely allied with these deep-water genera.
A partial skeleton of the basal mosasaur Halisaurus platyspondylus from the Severn Formation (Upper Cretaceous: Maastrichtian) of Maryland
Authors: Holmes Robert B. , Sues Hans-Dieter
Published: August 2016

A new specimen of the basal mosasaur Halisaurus platyspondylus from the Severn Formation of Prince Georges County, Maryland (Upper Cretaceous: middle Maastrichtian) represents the most complete partial skeleton of this uncommon taxon to be described to date. The characteristic dorsoventral compression of the vertebral centrum is most pronounced in the anterior trunk vertebrae, and the centra of the posterior trunk vertebrae exhibit proportions more similar to those in other mosasaurs such as Plioplatecarpus. The postorbitofrontal forms its primary contact with the frontal rather than the parietal, and the supraoccipital is firmly attached to the ventral side of the parietal. The plane of articulation between the parietals and supratemporal is neither vertical (as in Varanidae) nor horizontal (as in Mosasauridae), but forms an angle of about 55 degrees with the horizontal. The quadrate bears a long, ventrally-flared suprastapedial process but appears to lack an infrastapedial process. Close similarities in the structure of the frontal and parietal with “Clidastes” sternbergii support referral of the latter to Halisaurus, but reference of Phosphorosaurus ortliebi to Halisaurus is questionable. Halisaurus has been recorded from the Santonian to the late Maastrichtian.
Youngest record of tentaculitoids:Hidagaienitesnew genus from near the Carboniferous-Permian boundary in central Japan
Authors: Niko Shuji
Published: August 2016

A new genus and species of tentaculitid,Hidagaienites arcuatus, is described from calcareous beds near the Carboniferous–Permian boundary in the Hida-Gaien Terrane, Central Japan. Its mode of occurrence excludes the possibility that the specimens are derived from older strata. Thus, this tentaculitid represents the youngest record of the class Tentaculitoidea, which was previously thought to have become extinct in the Late Devonian.
Paleobiologic and evolutionary significance of corallite increase and associated features inSaffordophyllum newcombae(Tabulata, Late Ordovician, southern Manitoba)
Authors: Lee Dong-Jin , Elias Robert J.
Published: August 2016

Saffordophyllum newcombaeFlower, 1961, displays unique abilities and an unprecedented range in types of corallite increase. Cerioid growth was characteristic, but colonies on soft substrates could grow in a tollinaform manner during early astogeny. The capacity for recovery from damage and partial mortality is amazing. Rejuvenation may have been accompanied by peripheral expansion in some cases. Rapid regeneration could involve axial increase. Circular lacunae that formed during recovery became sites of rapid lateral increase or corallite decrease.

Two types of axial increase occurred within coralla. Lateral increase was concentrated mainly along the basal wall and adjacent to certain circular lacunae. In typical cerioid parts of the corallum, lateral increase seldom yielded “adult” corallites, but incipient lateral offsets could be numerous. The level of colony integration was probably moderately high. There was likely soft-tissue continuity among polyps, coordination of polyp behavior, subjugation of individuals for the good of the colony, and perhaps astogenetic control.

Saffordophyllum newcombaeis considered to be a tabulate coral, although one type of axial increase is similar to that in a few rugose corals and the other type of axial increase as well as possible peripheral expansion resemble modes of increase in some coralline sponges. Lateral increase is considered compatible with cnidarian rather than poriferan biology. Corallite size is typical of tabulates.Saffordophyllummay not be the direct ancestor of favositid tabulates, and may not even be closely related to them;S. newcombaeis very different fromPaleofavositesandFavosites.

The remarkable range in forms of increase discovered inS. newcombaedemonstrates the critical need for detailed paleobiologic studies, if we are to understand the early evolutionary history of corals and to establish reliable criteria for distinguishing various coral groups and homeomorphs.
Revision ofTenticospiriferTien, 1938, and similar spiriferid brachiopod genera from the Late Devonian (Frasnian) of Eurasia, North America, and Australia
Authors: Ma Xueping , Day Jed
Published: August 2016

The cyrtospiriferid brachiopod genusTenticospiriferTien, 1938, is revised based on restudy of the type species from the Frasnian (Late Devonian) of the Russian Platform. As revised the genus includes cyrtospiriferid species with pyramidal ventral valves, catacline ventral interareas, a narrow delthyrium, few sinal plications, and lack a median dorsal septum and pseudodeltidium. All species retained in the genus are of Givetian and Frasnian age. All Famennian age species described from South China and North America are rejected from the genus. It appears thatTenticospiriferevolved during the early Givetian in western Europe and remained endemic to that region during the remainder of the Givetian. Successive migrations ofTenticospiriferfrom eastern Laurussia to North America, then to South China and possibly Australia, coincided with middle and late Frasnian eustatic sea level rises, respectively. The North American speciesSpirifera cyrtinaformisHall and Whitfield, 1872, and related species identified asTenticospiriferby North American workers, are reassigned toConispiriferLyashenko, 1985. Its immigration to and widespread dispersal in carbonate platforms of western Laurussia, northern Gondwana and tropical island arcs (?) coincided with a major late Frasnian eustatic sea level rise. The new family Conispiriferidae is proposed withConispiriferLyashenko, 1985, selected as the type genus. The new family also includes the new genusPyramidaspiriferwithPlatyrachella altaFenton and Fenton, 1924, proposed as the type species. The affinity of the new family remains uncertain pending restudy of key genera currently included in the Superfamily Cyrtospiriferoidea. Available data from the Devonian brachiopod literature indicate that species ofPyramidaspiriferare restricted to late Frasnian deposits of central and western North America.
Systematics and biostratigraphy of halobiid bivalves from the Martin Bridge Formation (Upper Triassic), northeast Oregon
Authors: McRoberts Christopher A.
Published: August 2016

A diverseHalobiafauna with rare ammonoids and conodonts is described from the type Martin Bridge Formation (Upper Triassic) of northeast Oregon. The composite section of black shale, mudstone, bedded micrite, limestone conglomerate, and halobiid lumachelle spans the Carnian–Norian boundary without apparent sedimentologic break or pronounced biotic extinction. The occurrence ofHalobia radiata radiataGemmellaro,Halobia? cf.teltschenensis(Kittl),H. superba superbaMojsisovics, andH. superba ornatissimaSmith (nomen translatum) with the ammonoidsDiscotropitessp. andArietoceltites? sp. low in the section indicates a late Carnian age (Dilleri?, Welleri to Macrolobatus Zones). These fossils occur below beds containing early Norian (Kerri Zone)H. beyrichi(Mojsisovics) and middle Norian (Rutherfordi?, Columbianus Zone)H. haloricaMojsisovics. The described fauna increases the halobiid and ammonoid diversity previously known from the Martin Bridge Formation despite synonymy of species previously reported from the section.
The Oligocene rodentIschyromysof the Great Plains: replacement mistaken for anagenesis
Authors: Heaton Timothy H.
Published: August 2016

Ischyromys, the most abundant early Oligocene rodent from the Great Plains, has been considered by some workers to represent a single gradually evolving lineage comprising three or more chronospecies. Statistical investigation of large samples suggest instead that two closely related species coexisted, and the shift in mean size that was thought to represent anagenesis actually represents replacement. In Nebraska and eastern Wyoming bothI. parvidens(small) andI. typus(large) were rare but of equal abundance in the Chadronian,I. parvidenswas more prevalent in the early Orellan, andI. typuswas more prevalent in the middle and late Orellan. In northeastern Colorado, northern South Dakota, and North DakotaI. typusis the only species ofIschyromysfound in Orellan deposits, thus showing that the two species had differing geographic ranges.

The mean size ofI. typusdoes increase up section at all localities, but this change is minor and not deserving of chronospecies recognition. Much of this change occurred in the latest Orellan and earliest Whitneyan asI. typusapproached extinction, and it was accomplished mostly by loss of small individuals rather than a shift of the entire distribution. Rate of evolutionary change inIschyromysis found to be inversely correlated with population size, and no new species arose during the Orellan whenIschyromyswas most abundant.
Taxomomic validity of the ceratopsid dinosaur Ugrosaurus olsoni (Cobabe and Fastovsky)
Authors: Forster Catherine A.
Published: August 2016

Ceratopsid diversity at the end of the Cretaceous plays a role in interpreting faunal events at or near the Cretaceous–Tertiary boundary in North America. The addition of a new ceratopsid genus within this time frame thus has potential ramifications for the interpretation of these events.
Devonian Dentalium martini Whitfield, 1882, is not a mollusk but a worm
Authors: Yochelson Ellis L. , Goodison Ronald
Published: August 2016

Dentalium martini Whitfield, 1882, is a calcareous worm tube, not a mollusk, and is placed in synonymy of Coleolus crenatocinctum Hall, 1879. The growth of D. martini mimics logarithmic curvature in the holotype, but in other specimens shape varies from irregularly curved to straight. A prime reason for reassignment is variation of the wall thickness around the circumference in D. martini, which in late Paleozoic and Recent scaphopods of the same size is of uniform thickness.
Maastrichtian ammonites from Balochistan, Pakistan
Authors: Fatmi A. N. , Kennedy W. J.
Published: August 2016

Maastrichtian ammonites are described from two areas in Pakistan. The upper part of the lower unit of the Korara Shale in the southern Pab Range, Kirthar Province, southern Balochistan, is dated as Late Maastrichtian, based on the presence ofMenuites fresvillensis(Seunes, 1890), which is accompanied by abundantIndoceras baluchistanenseNoetling, 1897, commonBaculites ambatryensisCollignon, 1971, and rarerNeophylloceras surya(Forbes, 1846),Gaudryceras kayei(Forbes, 1846),Anagaudryceras politissimum(Kossmat, 1895),Kitchinites spenglerin. sp.,Pachydiscus (Pachydiscus) noetlingin. sp.,Libycoceras acutodorsatus(Noetling, 1897), andDiplomoceras cylindraceum(Defrance, 1816). A smaller assemblage from the Mughal Kot Formation near Kach, Suleman Province, northern Balochistan cannot be dated more precisely than Maastrichtian from the presence ofPachydiscus(Pachydiscus)neubergicus(Hauer, 1858), the first occurrence of which has been provisionally adopted by the Subcommission on Cretaceous Stratigraphy as marking the base of the Maastrichtian stage. It is associated with numerousEubaculites binodosus(Noetling, 1897).