On the Caobangiidae, a New Family

of the Polychaeta,

with a Redescription of

Caobangia billeti Giard

MEREDITH L. JONES

''\

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY • NUMBER 175
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SMITHSONIA N CONTRIBUTION S T O ZOOLOG Y • NUMBE R 17 5

On the Caobangiidae, a New Family of

the Polychaeta, with a Redescription

of Caobangia billeti Giard

Meredith L. Jones

SMITHSONIAN INSTITUTION PRESS

City of Washington

1974
ABSTRACT

Jones, Meredith L. On the Caobangiidae, a New Family of the Polychaeta, with

a Redescription of Caobangia billeti Giard. Smithsonian Contributions to Zoology, number 175, 55 pages, 25 figures, 11 plates, 3 tables, 1974.—The type-species

of Caobangia Giard, C. billeti Giard, is redescribed, primarily in terms of its setal

morphology. The description of six new species of Caobangia extends the distribution of the genus from North Vietnam to Thailand, Burma, Ceylon, India,

Bangladesh, Java, Sabah, Sarawak, and certain of the Philippine Islands. The

genus is associated with gastropod molluscs of the families Thiaridae, Pleuroceridae, and Viviparidae, and with the bivalve family Unionidae. Detailed observations on the external morphology and the anatomy of species of Caobangia, as

well as their setal structure and distribution, have contributed to the decision to

erect a separate family, the Caobangiidae, for the genus. Familial characters are:

the presence of neurosetal palmate hooks on the first setiger; the absence of

hooks of any sort on the following thoracic setigers; the presence of two types of

avicular hooks in the posterior region; and the recurving of the gut, within the

body, such that the anus opens anteriorly, in the region of the second to fourth

thoracic setiger. Anatomical observations on the branchial crown and its supporting skeleton, the nervous system, the nephridial ducts, and the reproductive

system of these hermaphroditic, larviparous, freshwater polychaetes are reported.

Further comments are made on larval morphology, settling, and metamorphosis,

as well as on the molluscan associates and their habitats, and some basic questions of biological import posed by the morphology, anatomy, and development

of Caobangia are propounded.

OFFICIAL PUBLICATION DATE is handstamped in a limited number of initial copies and is recorded

in the Institution's annual report, Smithsonian Year. SI PRESS NUMBER 5088. SF.RIES COVER DESIGN:

The coral Monastrea cavernosa (Linnaeus).

Library of Congress Cataloging in Publication Data.

Jones, Meredith L.

On the Caobangiidae, a new family of the Polychaeta, with a redescription of Caobangia billeti

Giard.

(Smithsonian contributions to zoology, no. 175)

Supt. of Docs, no.: SI 1.27:175

Bibliography: p.

1. Caobangiidae. 2. Caobangia billeti. I. Title. II. Series: Smithsonian Institution. Smithsonian contributions to zoology, no. 175.

QL1.S54 no. 175 [QL391.A6] 59P.08s [595M47] 74-1148

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Contents

Page

Introduction 1

Materials and Methods 3

Characteristics of the Genus Caobangia Giard 3

Caobangia Giard, 1893 . 8

Caobangia billeti Giard 11

Caobangia brandti, new species 12

Caobangia abbolti, new species 13

Caobangia morrisoni, new species 15

Caobangia smithi, new species 16

Caobangia indica, new species 18

Caobangia ceylonica, new species . 19

Comparison of Species of Caobangia . 20

Key to Species of Caobangia . 23

Morphological Observations . 24

The Taxonomic Status of Caobangia . 30

General Comments on Caobangia 31

Literature Cited 32

On the Caobangiidae, a New Family of

the Polychaeta, with a Redescription

of Caobangia billeti Giard

Meredith L. Jones

Introduction

In 1893 Giard described a bizarre sabelliform

polychaete from the fresh waters of what was then

known as Tonkin, in southeast Asia. The specimens were associated with a freshwater snail,

identified by Giard as a species of Melania, and

were found in blind-ending, teardrop-shaped burrows in the calcium carbonate shell of the snails.

In the course of his description of Caobangia

billeti, which was unaccompanied by figures, Giard

described a number of unusual and peculiar anatomical and morphological characters: the gut is

recurved within the body and the anal opening

is in the anterior part; the branchial crown is supported by an extensive internal structure; aside

from the placement of setal fascicles, there is no

trace of the usual annelid segmentation; the species

has an hermaphroditic mode of reproduction,

fertilization is internal, and larvae develop within

the body of the adult; the worms are capable of

making burrows in the calcium carbonate of snail

shells; and unique palmate neuropodial hooks are

present on the first setiger.

Giard's description was based on material collected by Albert Billet who, upon his return from

Tonkin (now North Vietnam), summarized his two

years of natural history observations at the village

of Cao Bang in northern Tonkin and mentioned

Meredith I.. Jones, Departtnent of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution,

Washington, D.C. 20560.

that the host snail of Caobangia billeti was closely

related to Melania aubryi Hende [sic] (Billet,

1896-98:64). In reporting upon the molluscs collected by Billet, Fischer (1898:327, pi. 18: fig. 42)

identified the host snail as Melania aubryana

Heude and presented a figure of the snail shell

bearing holes, the burrow openings characteristic

of Caobangia. Since these reports, the only other

citation in the literature based upon what might

be considered to be actual material is that of Lamy

and Andre (1936:954, fig. 3), who reproduced

Fischer's figure in demonstrating that Caobangia

is one of a number of annelids that burrow in

mollusc shells.

The remainder of the literature concerned with

Caobangia falls into a number of categories: (1)

as a sabellid of the subfamily Fabriciinae or as a

curious freshwater polychaete (Chamberlin, 1919;

Mclntosh, 1922; Zenkevitch, 1925; Monro, 1939;

Hartman, 1951, 1959; and Wesenberg-Lund, 1958);

(2) as a polychaete with a polytrochous larval stage

in its life cycle (Dawydoff, 1959); (3) as a suggested member of a new sabellid subfamily, the

Caobangiiniae [sic] (Chamberlin, 1919); and (4)

as a point of discussion in the somewhat heated

exchanges between Mesnil (1901a and b) and

Nusbaum (1901). Further, it is curious to note that

three extensive studies of the Sabellidae (Bush,

1904; Rioja, 1923; and Johansson, 1927) all cite

Giard's paper in their bibliographies, but do not

mention Caobangia in their texts.

It is unfortunate that Giard's description was
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

somewhat ambiguous, in part, for it led Nusbaum

(1901) and Hartman (1951) to conclude that the

anal opening was on the ventral surface rather

than the dorsal. In addition, Banse (1957:98-99)

concluded that Giard had made a bad choice of

words and really meant that the posterior end of

Caobangia was reflected under the ventral surface

of the worm, in much the same manner as is the

case in the Sabellariidae. Mesnil (1901a:272) and

Lamy and Andre (1936:954) also came to the same

conclusion.

It would seem that the remoteness of the typelocality and the small size of Caobangia account

for the fact that, aside from the initial collections,

no new material has been obtained for some 75

years. It came, therefore, as a pleasant surprise to

find that the shells of snails from Thailand, preserved in 70 percent ethanol and brought to my

attention by Dr. Joseph P. E. Morrison, Division

of Molluscs, National Museum of Natural History,

Smithsonian Institution, contained a considerable

number of well-preserved specimens of Caobangia.

A preliminary report on these, as well as on other

well-preserved material from Sabah [ = British

North Borneo], was concerned with the confirmation of Giard's observations on Caobangia and

conjectures as to the method of burrow-formation

(Jones, 1969).

Preliminary observations of the collections from

Thailand and Sabah led me to believe that the

structure of the palmate neuropodial hooks of the

first setiger would serve to discriminate among

species of Caobangia. Since these hooks are relatively large and were felt to be impervious to the

effects of drying (lamentably, curatorial procedures

for the molluscs do not coincide with those for the

worms), I conducted a search of certain of the

southeast Asian gastropod holdings of our Division

of Molluscs for snail shells showing signs of

Caobangia borings; these ultimately included the

families Thiaridae, Pleuroceridae, and Viviparidae.

Where Caobangia bore holes were found, indeed,

the palmate hooks were also found and their

structure has served as the basis of the systematic

section to follow. Further, these observations have

formed the basis for increasing the number of

species in the formerly monotypic genus to seven

and have allowed the extension of the distribution

of the genus from North Vietnam to Thailand,

Burma, Ceylon, India, Bangladesh, Java, Sabah,

Sarawak, and certain of the Philippine Islands. I

feel certain that further investigations will reveal

the genus to be widespread throughout the whole

of southeast Asia.

In spite of the fact that type-material of

Caobangia billed does not exist in the collections

of the Museum National .d'Histoire Naturelle,

Paris, I do not feel that any real purpose would

be served in designating a neotype for the species,

since the material upon which such a designation

would have to be based is most unsatisfactory because of its dried and fragmented condition; it is

suitable only for setal observations.

Where numbers have permitted, paratypic material has been deposited in the collections of the

following institutions: Allan Hancock Foundation,

Los Angeles (AHF); British Museum (Natural

History), London (BMNH); Museum of Comparative Zoology, Harvard University, Cambridge

(MCZ); Museum National d'Histoire Naturelle,

Paris (MNHNP); National Science Museum,

Tokyo (NSMT); Rijksmuseum van Natuurlijke

Historie, Leiden (RNHL); Universitetets Zoologiske Museum, Copenhagen (UZMC); Zoological

Institute, Academy of Sciences, Leningrad (ZIL);

Zoologische Museum, Amsterdam (ZMA); and

Zoologisches Museum, Hamburg (ZMH).

Since the collections of two divisions of the National Museum of Natural History, Smithsonian

Institution, are involved in the present study, it

was decided to preface catalog numbers (which still

carry the old designation for the United States

National Museum: USNM) of the Division of

Molluscs with "USNM-M" and those of the Division of Worms with "USNM-W."

With a few exceptions, so noted below, identifications of the molluscs, with which various species

of Caobangia are associated, are those appearing

on labels accompanying the individual molluscan

species. These have been accepted, out of hand, as

valid.

In view of the unique characters of the genus

Caobangia, its long-time obscurity, and the equivocal nature of portions of Giard's description, I

felt that the relatively large number of wellpreserved specimens might be utilized in enlarging

on an otherwise straight forward systematic account.

Thus, a series of observations follows, not only on

taxonomically important characters, but also on

the branchial crown and its supporting skeleton,
NUMBER 175

the nervous system, the nephridial ducts, and the

reproductive system, the latter including comments

on larval morphology and metamorphosis. All of

these observations have contributed to my judgement that the genus Caobangia should be separated from other sabelliform polychaetes in a

separate family, the Caobangiidae.

I would here thank the following colleagues for

their kind help and cooperation which have contributed so much to this paper: Dr. Joseph P. E.

Morrison, Division of Molluscs, National Museum

of Natural History, Smithsonian Institution, for

his first drawing my attention to specimens of

Caobangia and for subsequent discussions and

identifications of certain freshwater snails; Dr.

Joseph Rosewater, also of the Division of Molluscs,

for other discussions of the problems presented by

Caobangia and for the use of some photographic

equipment, especially the Faxitron Model 8050

X-ray apparatus which produced Figure 5b; Dr.

Rolph A. M. Brandt, then of the SEATO Medical

Research Project, Thailand (now of the School of

Tropical Medicine, Bangkok, Thailand), who

made the original Thai collections and augmented

these with others; Prof. E. Fischer-Piette, Museum

National d'Histoire Naturelle, Paris, and Dr.

Kenneth Boss, Museum of Comparative Zoology,

Harvard, both of whom made available to me specimens from their mollusc collections; Mr. Prasong

Temcharoen, now of the Academy of Natural

Sciences, Philadelphia, for assistance in determining the location of certain collection sites in

Thailand and Laos, as well as for a snail identification; and to Dr. Marian H. Pettibone, Division

of Worms, National Museum of Natural History,

Smithsonian Institution, for her cheerful and careful reading of the manuscript, which benefited

greatly from her comments and criticisms.

Materials and Methods

The polychaete specimens upon which this study

was based were obtained by decalcifying freshwater

mollusc shells that showed the characteristic bore

holes of Caobangia; this was done by placing the

shell in several changes of 5 percent nitric acid in

70 percent ethanol.

Histological observations were based on ethanolfixed specimens or, in the case of a few specimens,

especially provided by Dr. Brandt, on Bouin's fixed

material. Paraffin sections were cut at five or seven

microns and were stained in Mallory's Triple Stain.

Whole specimens, as well as decalcified molluscan

shell debris, were mounted in glycerine jelly.

Localities were determined by the use of various

gazetteers (War Department, 1944; National Intelligence Survey, 1952, 1953, 1962, 1964, 1966a, 1966b,

1968) and certain maps (especially "East Asia Road

Map," Series 1306, Edition 1-AMS (FE), U. S. Army

Map Service, 1965, Sheets 1 and 2, and "Continental Southeast Asia," Series 1206, Edition

4-AMS(FE), U. S. Army Map Service, 1965).

Characteristics of the Genus Caobangia Giard

Habitat: Figures 1-5 (C. brandti).

External morphology: Figures 6—8,

abbotti, C. brandti).

20 (C.

FIGURE 1.—Brotia (Paracrostoma) pseudosulcospira pseudosulcospira Brandt (USNM-M 704230): Showing truncated apex

of snail shell due to boring of Caobangia brandti, new

species (scale line is 10 mm).
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 2 Brotia (Paracrostoma) pseudosulcospira pseudosulcospira Brandt (USNM-M 704230): View of apex of snail

shell showing bore holes of Caobangia brandti, new species

(scale line is 1 mm).

m

•

• *

-

FICURK 3 Hyriopsis delaportei (Crosse and Fischer) (USNMM 70423G): Surface of a generally tangential split of clam

shell, showing transverse and longitudinal views of burrows

of Caobangia brandti, new species (scale line is 1 mm).

Internal anatomy: Figures 6, 21; Plates 1-11 (C.

abbotti, C. brandti).

Species of Caobangia bore into the shells of both

gastropod and bivalve molluscs (Figures 1-5). As

many as 28 adult Caobangia have been counted

from a single snail shell. The effect of these numerous bore holes, usually restricted to the apex

of the snail shell (Figure 3), weakens this portion

of the shell and results in a truncated profile (Figure 1). In the case of borings in bivalve shells, there

are many more specimens distributed throughout

the available surface (Figure 5). The teardropshaped burrows, which are lined with a thin,

secreted membrane, never connect with one

another, and the burrows are most often found in

the columellar area of the snails (Figure 4). Occasional bore holes may be found between adjacent

whorls of snail shells. Thus, adult specimens of

Caobangia appear to be restricted to the thicker

regions of calcium carbonate, although encapsulated metamorphosing larvae have been encountered all over the shell.

Specimens of Caobangia are herein reported

from the shells of the pleurocerid gastropods

Pahtdomus, Hcmimitra, Ganga, and TaruiHa; from

the thiarid gastropod genera Brotia, Balanocochlis,

Stenomelania, and Antimclania; from the viviparid gastropod genera Anulotaia, Cipangopaludina, and Mekongia; and from the unionid

bivalve genus Hyriopsis.

Since type-material of Caobangia billed Giard

does not exist, the following morphological account

is based on well-preserved specimens of C. brandti

from Thailand and C. abbotti from Sabah, Malay-
NUMBER 175

FIGURE 4.—Brotia (Brotia) binodosa binodosa (Blandford)

(USNM-M 704232): Apical view of partly decalcified snail

shell, showing Caobangia brandti, new species (USNM-W

50857), in situ beneath the periostracum (scale line is 1 mm).

sia (Figures 6-8); that of the setae (Figure 11)

comes from observations of dried specimens of C.

billeli from That Khe, about 55 km from the typelocality and in the same river system.

Caobangia species include sabelliform polychaetes up to 5 mm in length with the branchial

crown (BC) composed of three pairs of radioles

(DR, MR, VR), each provided with pectinately

or bipectinately arranged pinnules (Figures 6, 20).

The body tapers from its widest (posterior) part,

called the basal end by Jones (1969:830-831 ), 1 to

1

 In my earlier treatment of Caobangia I was, perhaps,

somewhat overzcalous in emphasizing the internal anterior

migration of the ascending gut and the opening of the anus

so far forward. In changing terminology from "basal" to

"posterior" and from "apical" to "anterior" I do not mean

to lessen this emphasis, but do so merely to avoid confusion.

the narrowest (anterior) region bearing the

branchial crown.

The first four setal fascicles are more crowded

than the next three. There is no collar, although

a rudimentary ventral process may be present

(Figure 8c). On the ventral surface there are

usually relatively large pigmented areas (VP) at

the level of the first to second or third setal fascicles and another at the level of the sixth to

seventh (Figures 6fl, 7, 8c). In addition, smaller

pigmented patches are distributed along the length

of the ascending gut (Figures 7, 8c). In all adult

specimens, developing eggs and larvae are readily

seen through the body wall in the posterior third

of the body. Histological sections have shown the

presence of both eggs and sperm in all animals

sectioned.

The first apparent thoracic segment bears a dorsal bundle of limbate capillary setae (LCS) and a

ventral group of palmate hooks (PH) with a central fang encircled by a series of 4-15 teeth (Figures

6, 9, Had). The hooks are oriented such that the

teeth are directed posteriorly and somewhat dorsally (Figure 9). One of the lateral teeth in the

arcuate series is quite often longer and/or stouter

than the others; this tooth is always ventralmost

(Figure 9c-/). New palmate hooks are generated

at the ventral end of a given series, as suggested by

the location of worn hooks and of embedded developing hooks (Figure 9b,e). The number of teeth

in the arcuate series, as well as the relative length

of the lateral teeth of the series, provide criteria

for specific determinations. The setae of the second

to seventh setal fascicles (SF) are composed usually

of unilimbate capillaries of two types; upper,

longer capillaries identical to the capillaries of the

first fascicle, provided with nearly uniform, narrow

limitations; and lower, shorter capillaries with

basally widened limbations (Figures 6a, 10, lld,e).

In the ventral part of the abdomen a somewhat

shortened version of the limbate capillaries (SBS)

are present in fewer numbers per fascicle (Figures

da, 11/). These are associated with more dorsal,

low, short-necked avicular hooks (AH), arranged

in 3-14 rows (Figure 6a). The hooks are provided

with a single larger tooth and numerous small

teeth, 10-14 rows with about five or six per row

(Figure lie). The first row may have as many as

116 hooks on each side; more posteriorly, the number of hooks per row decrease until the last row is
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Fici'RF. 5.—Hyriopsis delajyortei (C'.rosse and Fischer) (I'SNM-M 704230): a, outer surface of

broken left valve showing bore holes of Caolxingia brandti, new species, and external tubes of

freshwater sabellid, Momoiku sp. (center); b, X-iay photograph of the same valve, showing the

shape and number of burrows, as well as their lack of common orientation.
NUMBER 175

BCLG

10

AG

N

N

N

N

N

N

N

N

1

2

3

4

5

6

7

8

LG

Fici.'RE (5. Idealized and generalized drawings based upon Caobangia nbbotli, new species: a,

lateral view, showing external morphology and location of various types of setae; b, doisal view,

showing internal structures (setae and tips of branchial crown omitted). (1-10 = levels at which

sections in Plates l-."» were taken. All = abdomen, \C. = ascending gut. All = low avicular

hooks. AN = ascending nepln idial duct. AO = anal opening. BC = branchial crown. IK. =

descending gut. ON = descending nephridial duct. I.CS = limbate capillary setae. I.I) = larval

duct. I.DO = larval duct opening. I.G = loops of gut. X 1 —11 = levels at which sections in

Plates fid-Wd weie taken. NPR = nephi idiopore, NS I 1 and '_' = first and second nephrostomes

of the descending nephridial dud . I'll = palmate hook (s), SIJS = shoi t limbate and buishlike

setae. SC = stomachic chamber of the- descending gut. SO = speim duct. SKI = fomth thoiatic

setal fascicle. I = "testis,' IAH = tall a\ ic ulai hook («,), I M = thorax, T O = external opening

of the "testis." \'P = ventral pigmentccl aiea; line stippling = gut. coarse' stippling = "testis,"

wavy lines = larval ducts.)
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 7.—Caobangia brandli, new species: lateral (anterior)

to ventral (posterior) view (specimen twisted).

represented by but one or two hooks. Posterior to

the region of avicular hooks, the limbate capillaries

lateral to the ascending gut become still shorter

and may be bilimbate or unilimbate (Figures Hg-i;

the mucronate setae with symmetrical and asymmetrical limbations, respectively, of Giard, 1893:

475?). In most cases the abdominal limbate capillaries finally are replaced by brushlike setae with

blunt tips, and having a generally frayed appearance (Figures \\j,k, 12e,/). These last are usually

accompanied by some tall, long-necked avicular

hooks (TAH) (Figures 6a, llm).

The mouth, located at the center of the branchial crown, leads to a narrow passage, the descending gut (DG); at about the midpoint of the body,

the gut enlarges to form a stomachic cavity (SC)

which occupies most of the posterior half of the

worm (Figure 6, Plates 1-4, 7, 10). More posteriorly, a narrowed gut emerges, forms several loops

(LG), and turns forward within the curve of the

posterior end, forming the ascending gut (AG)

(Figure 6, Plates 1-5). As it progresses anteriorly,

the ascending gut forms an increasingly pronounced ridge under the body surface (Figures 7,

8c). Somewhat posterior to the seventh setiger it

curves dorsally, almost invariably on the right

side, and continues in the middorsal line to the

level of the second to fourth setiger where it terminates in the anal opening (Figure 6, AO). The

dorsal areas anterior to the anus and between the

setal fascicles on either side together form a wide

longitudinal ciliated field (LCF) which continues

anteriorly to the base of the branchial crown

(Plates 1, 8, 9).

The separation of abdomen and thorax is assumed to be just posterior to the seventh setiger,

in the region of the dorsal turn of the ascending

gut, anterior to the first row of low avicular hooks

(Figure 6, AB-TH). The latter, together with

their ventrally placed capillary setae, are felt to

represent the "inverted" condition of abdominal

setae of other sabelliform polychaetes.

Caobangia Ciard, 1893

TYPE-SPECIES.—C. billeti Giard, 1893, by monotypy.

GENDER.—Feminine.

DIAGNOSIS.—Small sabilliform polychaetes burrowing in shells of freshwater molluscs; 3 pairs
NUMBER 175

FIGURE 8 Caobangia abbotti, new species: a, dorsal view; b, lateral view, right side; c, ventral

view; d, lateral view, left side.

of radioles; thoracic region with 7 setal fascicles

of limbate capillary setae (notopodial); palmate

hooks on first setiger (neuropodial); abdominal

region with short limbate capillary neurosetae and

notopodial avicular hooks, short in midregion, tall

in posterior region; terminal portion of gut opening on dorsal surface of anterior thoracic region;

hermaphroditic and larviparous.
10

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 9.—Caobangia spp., palmate hooks from first thoracic setigers: a, C. brandti, new species,

right side (USNM-W 50615); b, C. abbotii, new species, right side (USNM-W 50644); c, C.

morrisoni, new species, left side (USNM-W 50640); d, C. smithi, new species, right side (U.SNMW 50611); e, C. indica, new species, left side (USNM-W 50636); /, C. ceylonica, new species, right

side (USNM-W 50632). (All emergent hooks of each series are shown in actual orientation; dorsal

is top of figure, anterior ends of specimens are indicated by arrows.)

0.05 mm

FIGURE 10.—Caobangia abbotti, new species: Anterior view of third right thoracic setal fascicle,

showing relationship of longer (upper) and shorter (lower) limbatc capillary setae.
NUMBER 175 11

Caobangia billeti Ciard

FIGURE 11

Caobangia bilteti Giard, 1893:473-476 Billet, 1896-98:64.—

Fischer, 1898:329, pi. 18: fig. 42 Lamy and Andre, 1936:

954, fig. 3.

MATERIAL EXAMINED.— [1]

 2 That Khe, Tonkin

[North Vietnam] (22°16'N, 106°28'E), from

Melania aubryana Heude \_=Brotia sp., fide J. P.

E. Morrison] MNHNP, Lavezzari Collection,

USNM-W 50643, dry material.

DISPOSITION OF ADDITIONAL MATERIAL.—MNHNP

AE 1094.

DESCRIPTION.—Since all material was obtained

from a dried snail shell, little can be said of the

overall morphology of the specimens referred herein to C. billeti; however, all setal types characteristic of the genus have been recognized. The palmate

hooks from the first setiger (Figure lla-c) bear

from 7 to 12 teeth in the arcuate series, the ventral

lateral tooth may be rather stout, and both lateral

teeth are usually somewhat longer than the others.

The upper capillary setae of the 7 thoracic setigers

are provided with narrow, relatively long limbations (Figure lid); the lower capillary setae of the

2

 Bracketed numbers appearing in this and following "Material Examined" sections are keyed to localities shown on

the maps of Figures 18 and 19.

second to seventh setigers bear limbations which

are basally broad and abruptly narrowing apically

(Figure lie). Abdominal avicular hooks have a

rather low profile (Figure 11/). According to Giard

(1893), the abdominal hooks may be disposed in

3 or 4 rows, with up to 100 hooks in the first row

and decreasing numbers in subsequent rows; in the

specimens from That Khe, as many as 4 rows were

observed. The anterior abdominal capillary setae

are short and narrowly limbate (Figure 11/) and

are ventral to the low avicular hooks. Posterior to

the avicular hooks, several types of capillary setae

are distributed along both sides of the ridge of the

ascending gut: narrowly limbate capillaries give

way to broadly unilimbate or bilimbate capillaries,

and these, in turn, to capillaries with very short,

broad limbations (Figure llg-k). Those of the

latter type are, perhaps, comparable to the brushlike setae of other species of Caobangia; they are

usually abruptly bent at their tips. Dorsal to the

latter are tall, long-necked avicular hooks; these

are rather small, with the single basal tooth nearly

appressed to the neck (Figure llm).

REMARKS.—Caobangia billeti is known only from

the type-locality, Cao Bang, and from That Khe;

both are in North Vietnam, in the drainage of the

Kiang River, which terminates at Canton, China,

about 750 km to the east (Figure 19).

0.05 mm

r

FIGURE 11.—Caobangia billeti (USNM-W 50643): a-c, palmate hooks from first thoracic setiger;

d, longer thoracic limbate capillary seta; e, shorter thoracic limbate capillary seta; /, anterior

abdominal limbate capillary seta; g-i, middle abdominal short limbate capillary setae, /', k,

posterior abdominal brushlike (?) setae; /, anterior abdominal low avicular hook; m, posterior

abdominal tall, long-necked avicular hook.
12

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Caobangia brandti, new species

FICURES 1-5, 7, 9a, 12

Caobangia sp. [in part] Jones, 1969: figs. 1, 4-8.

MATERIAL EXAMINED.—Thailand: [1] Maenam

Kaek [Kaek River] at Sakunothayan Waterfall

[Wang Nok Nang Aen Waterfall], about 33 km

east of Phitsanulok, Phitsanulok Province

(16°51'N, 10O°32'E), from Brotia (Paracrostoma)

pseudosulcospira pseudosulcospira Brandt (USNMM 704230), coll. R. A. M. Brandt, 6 January 1968

(USNM-W 50663, holotype; USNM-W 50614,

50622-26, 50630, paratypes), wet and dry material;

[2] Maenam Kaek at Gaeng Song Waterfall, about

45 km east of Phitsanulok, Phitsanulok Province

(16°49'N, 100°36'E), from Brotia (Paracrostoma)

pseudosulcospira armata Brandt (USNM-M 704231),

coll. R. A. M. Brandt, 6 January 1968 (USNM-W

50615, paratypes), wet and dry material; [3] Kaek

Noi River at Thung Salaeng Luang Botanical

Garden, about 71 km east of Phitsanulok, Phitsanulok Province (16°52'N, 100°47'E), from Brotia

(Brotia) binodosa binodosa (Blanford) (USNM-M

704232), coll. R. A. M. Brandt, 16 December 1967

(USNM-W 50616, 50627-29, paratypes), wet and

dry material; [4] Huai Chieng Nam [part of the

Kaek Noi River], about 90 km east of Phitsanulok,

Phitsanulok Province (16°48'N, 100°55'E), from

Brotia (Brotia) binodosa subgloriosa Brandt

(USNM-M 704233), coll. R. A. M. Brandt, 17 May

1966 (USNM-W 50617, paratypes), wet and dry

material; [5] Maenam Chi [Chi River] near

Sarakham, Maha Sarakham Province (16°12'N,

103°17'E), from Anulotaia cf. mekongensis Brandt

(USNM-M 419887), coll. H. M. Smith, 21 March

1929 (USNM-W 50618, paratypes), dry material.

Laos: [6] Sedone River at Pakse (15°08'N,

FIGURE 12—Caobangia brandti, new species: a, palmate hook from first thoracic setiger; b,

longer limbate capillary seta from third thoracic setiger; c, shorter limbate capillary seta from

same; d, shorter limbate capillary seta from anterior abdomen; e, f, posterior abdominal brushlike setae; g, anterior abdominal low avicular hook; h, posterior abdominal tall, long-necked

avicular hook (a-h, USNM-W 50614); i, palmate hook (USNM-W 50617); /, palmate and avicular hooks (USNM-W r>06ir>); k, same (USNM-W .50616); /, same (USNM-W 50617); m, palmate

hook (USNM-W 50618); n, palmate and avicular hooks (USNM-W 50619); o same (USNM-W

50620); p, same (USNM-W 50621).
NUMBER 175 13

105°48'E), from Cipangopaludina chinensis Gray

(USNM-M 704234), coll. R. A. M. Brandt, 14

March 1968 (USNM-W 50619, paratypes), dry

material; [7] Mekong River at Ban Don Det,

south of Khong Island, Sithandone (14°07'N,

105°48'E), from Mekongia jullieni (Deshayes)

(USNM-M 704235), coll. R. A. M. Brandt, 13

March 1968 (USNM-W 50620, paratypes), dry

material; [8] Mekong River at Ban Seo, south

of Khong Island, Sithandone (14°06'N, 105°51'E),

from Hyriopsis delaporlei (Crosse and Fischer)

(USNM-M 704236), coll. R. A. M. Brandt, 6

March 1968 (USNM-W 50621, paratypes), dry

material.

DISPOSITION OF ADDITIONAL PARATYPES.—AHF

Poly 1090; BMNH ZB 1973.121; MCZ; MNHNP

AE 1092; NSMT Pol. P 102; RNHL 14772; UZMC;

ZIL; ZMA Pol. 2600; ZMH 13529.

DESCRIPTION.—The external morphology of C.

brandti agrees with the account given above in

characterizing the genus (Figure 7). The first

thoracic setiger has 4 to 8 long unilimbate capillaries and 3 to 5 palmate hooks. Palmate hooks

bear from 5 to 9 teeth above the central fang (Figures 9a, 12a,i-p). The terminal teeth in the series

are subequal in length and stoutness, and they

may be slightly longer and stouter than the more

central teeth, which may alternate in length.

Thoracic setigers 2 to 7 bear unilimbate capillary

setae in progressively decreasing numbers: from 7

to 1 longer upper ones and from 5 to 1 shorter

ventral ones (Figure 12b,c). The abdominal segments begin at a point where the ascending gut has

a midventral location. There may be as many as

11 rows of low avicular hooks (Figure 12g,j-l,n-p);

each row is accompanied by 1 or 2 short limbate

capillary setae just lateral to the ascending gut.

The first row may be composed of up to 65 individual hooks, their numbers decreasing progressively. One individual with 11 rows showed the

following sequence: 54; 56; 20; 34; 32; 23; 12; 1;

3; 1; and 2. At or beyond the last rows of hooks the

accompanying limbate capillary setae are replaced

by yet shorter capillaries and these, in turn, by

single blunt, brushlike setae (Figure \2d-f). Finally,

the last 2 to 5 of the brushlike setae are accompanied by single, tall, long-necked avicular hooks

(Figure 12h). As many as 27 setal fascicles have

been observed, which suggests the presence of at

least that number of obscured segments. Apart

from the inner ends of the setal fascicles and, to

some extent, the extensions of the branchial

crown skeleton, the internal anatomy shows no

segmentation.

REMARKS.—Caobangia brandti differs from C.

billeti in having relatively longer thoracic setae,

the upper ones having a basally expanded limbation, in having palmate hooks with fewer terminal

teeth, in having more rows of abdominal avicular

hooks and fewer of them in the first transverse

row, and in having larger, long-necked avicular

hooks. Further, C. brandti is confined to the drainages of the Mekong and Chao Phraya rivers (Figure

19). It should be noted that C. brandti was found

in association with various thiarid and viviparid

gastropods, as well as with the unionid bivalve

Hyriopsis delaporlei.

I take pleasure in naming this species for Dr.

R. A. M. Brandt, School of Tropical Medicine,

Bangkok, Thailand, who most kindly supplied me

with the preserved material and identifications of

these Thai and Laotian molluscs.

Caobangia abbotti, new species

FIGURKS 8, 9b, 10, 13, 20

Caobangia sp. [in part] Jones, 1969: figs. 2, 3.

MATERIAL EXAMINED.—Malaysia, Sabah: [1]

Mile 4, Tambunan Trail, Ranau (05°58'N, 116°

41'E), from Brotia pageli (Thiele) (USNM-M

608099), coll. B. C. Walton, 30 August 1953

(USNM-W 50669, holotype; USNM-W 50644,

50654-60, paratypes), wet and dry material; [2]

Gomatong, near Kinabatangana (05°42'N, 118°

23'E), from Brotia pontificalis pageli (Thiele)

(MCZ 185605), coll. H. G. Keith (USNM-W 50645,

paratypes), dry material; [3] Penokok River, near

Kiau, Mt. Kinabalu (06°03'N, 116°31'E), from

Brotia pontificalis agrestis (Reeve) (USNM-M

590308), elevation 4,000 feet (USNM-W 50646,

paratypes), dry material. Malaysia, Sarawak: [4]

Robin River at Dana Amu (01°03'N, 110°26'E),

from Brotia pontificalis von deni Busch (MCZ

227189), coll. D. Thomas, 1956 (USNM-W 50647,

paratypes), dry material. Republic of the Philippines, Mindanao Island, [5] San Ramon River,

San Ramon [30 km northeast of Zamboanga]

(07°00'N, 121°55'E), from Balanocochlis glans
14

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Philippi (USNM-M 591929), coll. M. E. McDonald,

"attached to large rocks in rushing current"

(USNM-W 50648, paratypes), dry material; [6]

San Ramon River, San Ramon (07°00'N,

121°55'E), from Balanocochlis glans Philippi

(USNM-M 543951), coll. R. T. Abbott, 1945

(USNM-W 50649, paratypes), dry material. Palawan Island: [7] Qwahig River, Puerto Princesa

(09°44'N, 118°44'E), from Stenomelania sp.

(USNM-M 259372) (USNM-W 50650, paratypes),

dry material. Samar Island: [8] Basey (11°17'N,

125°04'E), from [?] Antimelania asperata (Lea),

(USNM-W 311026), coll. M. Smith (USNM-W

50651, paratypes), dry material; [9] Stream just

east of Napuro (12°02'N, 124°42'E), from Stenomelania sp. (USNM-M 543943), coll. R. T. Abbott,

7 July 1945, water temperature 80°F (USNM-W

50652, paratypes), dry material. Luzon Island: [10]

o a

0.05 mm

FIGURE 13.—Caobangia abbotti, new species: a, palmate hook from first thoracic setiger; b,

longer limbate capillary seta from second thoracic setiger; c, shorter unilimbate capillary seta

from same; d, shorter bilimbate capillary seta from same; e, abdominal limbate capillary seta

associated with low avicular hooks; /, short abdominal limbate capillary seta; g, h, abdominal

brushlike setae; i, low avicular hook; ;, tall, long-necked avicular hook (a-j, USNM-W 50644);

k, palmate hook (USNM-W 50645); /, palmate and avicular hooks (USNM-W 50646); m, same

(USNM-W 50648); n, same (USNM-W 50649); o, one adult (left) and two juvenile (right)

palmate hooks (USNM-W 50650); p, palmate and avicular hooks (USNM-W 50651); q, palmate

hook (USNM-W 50652); r, palmate, low avicular, and tall, long-necked avicular hooks

(USNM-W 50653).
NUMBER 175 15

Jovellar River, Jovellar (13°04'N, 123°36'E), from

Brotia dactylus Lea (MCZ 96693), coll. P. de Mesa

(USNM-W 50653, paratypes), dry material.

DISPOSITION OF ADDITIONAL PARATYPES.—AHF

Poly 1091; BMNH ZB 1973.122; MCZ; MNHNP

AE 1091; NSMT Pol. P 103; RNHL 14773; UZMC;

ZIL; ZMA Pol. 2601; ZMH 13530.

DESCRIPTION.—The external morphology of C.

abbotti agrees with the account given in the section on generic characteristics (Figures Sa-d, 20).

There are from 4 to 9 ventral palmate hooks in

the first setiger, and from 5 to 11 dorsal, very long,

limbate capillary setae, provided with narrow

limbations. The palmate hooks bear from 7 to 15

small teeth in an arc distal to the central fang and,

although the terminal teeth of the series are

stouter than the others, they may be subequal, to

perceptibly longer than the others (Figures 9b,

\$a,k-r). Thoracic setigers 2 to 7 bear unilimbate

capillary setae in progressively decreasing numbers:

from 14 to 2 longer upper ones, and from 10 to 1

shorter ventral ones (Figures 10, \Sb-d). The anterior abdominal region usually has from 3 to 8 transverse rows of low avicular hooks (14 rows on one

specimen) (Figures 8, 13i); the first row may contain as many as 116 individual hooks, their numbers decreasing progressively. One individual with

6 rows showed the following sequence: 104; 75;

58; 26; 8; and 5. The hooks are accompanied by

up to 5 short capillary setae (Figure 13e). Posterior

to the region of hooks the limbate capillary setae

are similar, but shorter; in the posterior region

they are blunt and brushlike (Figure 13/-/?). The

last 2 to 4 brushlike setae may be accompanied by

from 1 to 3 tall, long-necked hooks (Figure 13;).

As many as 37 obscured segments are reflected by

the 37 fascicles observed along the length of the

body of one specimen.

REMARKS.—Caobangia abbotti differs from C.

billed in the size of long-necked avicular hooks

and the length of dorsal thoracic capillary setae,

from C. brondti in the length and type of limbations of the dorsal thoracic capillary setae and the

number of low avicular hooks in the first abdominal row, and from both in the number of teeth on

the palmate hooks and in the number of rows of

abdominal low avicular hooks.

Caobangia abbotti is distributed throughout the

Philippine Islands and Borneo (Figure 18). It

should be noted that differences in the shapes of

long-necked hooks and in the lengths of the end

teeth in the distal series of teeth of the palmate

hooks may, ultimately, necessitate the erection of

a separate species for the Philippine populations

(cf. Figure 13; and r); this must await the availability of more material. C. abbotti has, thus far,

been found associated with the thiarid snail genera

Brotia, Balanocochlis, Stenomelania, and Antimelania.

I take pleasure in naming this species for Dr.

R. Tucker Abbott, Delaware Museum of Natural

History, Greenville, whose contributions to malacology are too numerous to list here and who has

contributed to this study in having collected valuable material.

Caobangia morrisoni, new species

FIGURES 9C, 14

MATERIAL EXAMINED.—Indonesia, Java: [1]

Bogor (06°35'S, 106°47'E), from Brotia sp.

(USNM-M 261804), coll. O. Bryant and W. Palmer,

1909-1910 (USNM-W 50639, holotype; USNM-W

50640, paratypes), dry material; [2] Bogor

(06°35'S, 106°47'E), from Brotia sp. (USNM-M

261804A), coll. O. Bryant and W. Palmer, 1909-

1910 (USNM-W 50641, paratypes), dry material;

[3] Tjirebon [Cheribon] (06°44'S, 108°34'E),

from Brotia testudinaria (von dem Busch) (MCZ

215007), coll. A. J. de Wilde (USNM-W 50642,

paratypes), dry material.

DISPOSITION OF ADDITIONAL PARATYPES.—AHF

Poly 1093; BMNH ZB 1973.124; MNHNP AE

1093; ZIL.

DESCRIPTION.—Since C. morrisoni is represented

only by dry material, its description must be restricted to setal morphology. Palmate hooks from

the first thoracic setiger bear from 5 to 11 distal

teeth above the single central fang; the terminal

teeth are subequal and somewhat longer and

stouter than the others (Figures 9c, \Aa,b,j-l).

Capillary setae of the thoracic region are provided

with limbations which are but slightly inflated

proximally; the lower capillary setae of the second

to seventh setigers have proximally inflated limbations (Figure \Ac,d). Abdominal capillary setae

are similar to those previously described for C.

brandti (Figure \Ae-g). The anterior low avicular

hooks are unremarkable (Figure 14/*). The pos-
16

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

0.05 mm

f

FIGURE 14. Caobangia tnorrisoni, new species: a, palmate hook from first thoracic setigcr; b,

embedded palmate hook; c, longer limbate capillary seta from second thoracic setigcr; d, shorter

limbate capillary seta from same; e, anterior abdominal limbate capillary seta; /, abdominal

short limbate capillary seta; g, posterior abdominal brushlikc seta; h, low avicular hook; i, tall,

long-necked avicular hook; /, k, palmate hook (s); /, same, from juvenile, (a-e and h-j, USNM-W

50640; /, g, k, and /, USNM-W 50642).

terior long-necked avicular hooks are relatively

small, and there is a nearly perpendicular angle

between the single large tooth and the shaft (Figure

14/).

REMARKS.—Caobangia tnorrisoni differs from C.

billeli, C. brandti, and C. abbotti in the smaller

size of its long-necked avicular hooks and their

shape, as reflected by the angle between the shaft

and the single tooth; further differentiation lies

in the intermediate nature of the limbation of the

relatively short dorsal capillary setae of the thoracic

region.

Caobangia tnorrisoni is presently restricted to

the Indonesian island of Java and has been found

in association only with snails of the thiarid genus

Broiia (Figure 18).

I take pleasure in naming the species for Dr.

J. P. E. Morrison, National Museum of Natural

History, Smithsonian Institution, who not only first

drew my attention to specimens of Caobangia, but

who has been continually helpful in identifying

freshwater molluscs of southeast Asia for me and

in retrieving from the collections additional specimens bearing the characteristic bore holes of

Caobangia.

Caobangia smithi, new species

FIGURES 9d, 15

MATERIAL EXAMINED.—Thailand: [1] Huai

Charao, Charao Village, Mae Ramat District, Tak

Province (16°58'N, 98°34'E), from Brotia costula

siamensis Brot (USNM-M 704237), coll. R. A. M.

Brandt, 26 April 1967 (USNM-W 50605, holotype;

USNM-W 50606, paratypes) dry material; [2]

Salween River at Ban Chao Noi, Mae Hong Son

Province (approximately 18°26'N, 97°35'E),3

from Brotia cf. baccata (Gould) (USNM-M

420480a), coll. H. M. Smith, 14 January 1933

(USNM-W 50607, paratypes), dry material; [3]

'Certain of Smith's collection sites remain unknown; approximate latitudes and longitudes for this locality and two

others were deduced from dates and towns in Smith's known

itinerary during the period 13-15 January 1933 (Deignan,

1945:5-6) and from an item-by-item perusal of the dates of

locality records in Smith's (1945) monograph.
NUMBER 175 17

0.05 mm

FIGURE 15 Caobangia smithi, new species: a, b, palmate hooks from first thoracic setiger; c,

longer limbate capillary seta from third thoracic setiger; d, shorter limbate capillary seta from

same; e, short limbate capillary seta from abdomen; /, abdominal brushlike seta (a-f, USNM-W

50661); g, tall, long-necked avicular hook (USNM-W 50610); h, palmate and avicular hooks

(USNM-W 50607); i, same (USNM-W 50606); ;, palmate hook (USNM-W 50609); k, palmate

and avicular hooks (USNM-W 50610); I, adult (left) and juvenile (right) palmate Hooks

(USNM-W 50611); m, two adult (left) and one juvenile (right) palmate hooks (USNM-W

50612); n, palmate and two avicular hooks (USNM-W 50613); o, palmate and avicular hooks

(USNM-W 50661).

Salween River at Ta Ta Fang [ = Ban Tha Phang],

Mae Hong Son Province, (18°04'N, 97°43'E),

from Brotia cf. baccata (Gould) (USNM-M

420471), coll. H. M. Smith, 31 January 1933

(USNM-W 50608, paratypes), dry material; [4]

Maenam Moei, west of Mae Sot, Mae Sot District,

Tak Province (16°42'N, 98°32'E), from Brotia

costula siamensis Brot (USNM-M 704238), coll.

R. A. M. Brandt, 27 April 1967 (USNM-W 50609,

paratypes), dry material; [5] Huai Um Meng

[ = Huey Um Mong], Ching Mai Province

(18°25'N, 98°22'E), from Brotia sp. (USNM-M

420441), coll. H. M. Smith, 30 December 1931,

"mountain stream, 800 m altitude" (USNM-W

50610, paratypes), dry material. Burma: [6] Salween River at Ban Mae Hiek (approximately

18°50'N, 97°27'E), from Brotia cf. baccata (Gould)

(USNM-M 420467), coll. H. M. Smith, 13 January

1933 (USNM-W 50611, paratypes), dry material;

[7] Salween River at Chong Jam (approximately

18°03'N, 97°42'E), from Brotia cf. baccata (Gould)

(USNM-M 427278a), coll. H. M. Smith, 15 January

1933, "attached to rocks in swift water" (USNM-W

50612, paratypes), dry material; [8] Pegu,4 from

IPahidomus conica (Gray) (USNM-M 31430)

* At least three populated areas in Burma are known as

"Pegu": (1) 21°59'N, 95°32'E, near Mandalay, in the drainage of the Irrawaddy River (cf. Figure 19); (2) 24°29'N,

96°10'E, also in the Irrawaddy drainage (cf. Figure 18); and

(3) 17°21'N( 96°30'E, a city of nearly 50,000 inhabitants on

the Pegu River. I am inclined to believe that the third

Pegu is a valid locality for these specimens.
18

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

(USNM-W 50613, para types), dry material; [9]

Pegu, from Brotia gloriosa (Anthony) (USNM-M

43604) (USNM-W 50661, paratypes), dry material.

DESCRIPTION.—All specimens of this species have

been dried, and the description is based on setal

morphology. Palmate hooks of the first setiger bear

from 4 to 10 teeth above the single central fang;

both terminal teeth are longer, and usually stouter,

than the other teeth; the ventralmost terminal

tooth may be longer than the dorsalmost (Figures

9d, \ba,b,h-o). Upper capillary setae of the thoracic

region are provided with narrow limbations

similar to those of C. billeti (Figure 15c). Lower

capillary setae of the same region show typical

proximally inflated limbations (Figure 15rf). Abdominal capillary setae are typical (Figures 15^,/).

The low avicular Tiooks of the transverse rows are

also typical (Figure \bh,i,k,n,o). The posterior

long-necked avicular hooks are small and similar

to those of C. morrisoni (Figure 15g).

REMARKS.— Caobangia smithi differs from C.

brandti in the relative development of the limbation of the upper capillary setae of the thoracic

setigers. Other capillary setae and the low avicular

hooks do not serve to discriminate between C.

smithi and other species of Caobangia. Long-necked

avicular hooks are shorter and smaller than those

of C. billeti, C. brandti, and C. abbotti; the angle

between the single tooth and the shaft is more

acute than is the case in C. morrisoni.

Caobangia smithi is known from the drainages

of the Salween and Pegu-Sittang Rivers; there is a

record (Huai Um Meng, USNM-M 420441,

USNM-W 50610) from the drainage of the Chao

Phraya River of Thailand which will be discussed

below (Figure 19). Association has been observed

with snails of the thiarid genus Brotia and the

pleurocerid genus Pahidomits.

I take pleasure in naming this species for Dr.

H. M. Smith, who found time, while making collections of southeast Asian fish, to collect the snails

from which most of the descriptive data of this

species derive.

Caobangia indica, new species

FIGURES 9e, 16

MATERIAL EXAMINED.—India: [1] Kobo [40 km

southwest of Sadiya in the drainage system of the

Brahmaputra River], Assam (27°47'N, 95°23'E),

from }Antimelania menkiana (Lea) (USNM-M

433497), coll. D. E. Hardy, 15 March 1944

(USNM-W 50635, holotype; USNM-W 50636, paratypes), dry material; [2] Teri Ghat [in the drainage of the Ganges River, near the Nepalese border],

(27°19'N, 83°30'E), from Hemimitra stephanus

(Benson) (USNM-M 31434) (USNM-W 50637,

paratypes), dry material. Bangladesh: [3] Sylhet

[in the drainage of the Meghna River, a tributary

of the Ganges] (24°54'N, 91°52'E), from Hemimitra stephanus (Benson) (MCZ 256890) (USNMW 50638, paratypes), dry material.

DISPOSITION OF ADDITIONAL PARATYPES.—AHF

Poly 1092; BMNH ZB 1973.123; ZIL.

DESCRIPTION.—All specimens of this species have

been dried and the description is based upon setal

morphology. Palmate hooks of the first setiger bear

from 4 to 7 teeth above the single central fang

(Figures 9e, \6a,i,j). The terminal teeth are stouter

than the others; the dorsalmost tooth is somewhat

longer; the ventralmost tooth is from 2 to 3 times

the length of the intermediary teeth. Upper capillary setae of the thoracic region are provided with

a narrow limbation, and the lower capillary setae

have an expanded limbation more basally (Figure

\6b,c). Capillary setae of the abdomen become

progressively shorter toward the posterior end of

the worm and bear an expanded limbation (Figure \6d,e). The posterior brushlike setae are typical (Figure 16/). The anterior abdominal region

has 4 to 7 transverse rows of low avicular hooks,

similar to those of the other species of Caobangia

(Figure \6g,i,j). The long-necked avicular hooks

which accompany the brushlike setae are small and

similar to those of C. billeti (Figure \6h).

REMARKS.—Caobangia indica differs from all

species but C. billeti, in the size and shape of its

long-necked avicular hooks and differs only from

C. brandti with respect to the limbation of the dorsal thoracic capillary setae. The number of teeth

on the palmate setae, as well as the extreme length

of the ventralmost terminal tooth, differentiate C.

indica from both of the above-mentioned species.

Caobangia indica is known from the Ganges

River system (of which the Brahmaputra and

Meghna are tributaries) and is here associated

with pleurocerid (Hemimitra) and thiarid (Antimelania) snails (Figure 18).
NUMBER 175 19

0.05 mm

FIGURE 16 Caobangia indica, new species: a, palmate hook from first thoracic setiger; b, longer

limbate capillary seta from third thoracic setiger; c, shorter limbate capillary seta from same;

d, anterior abdominal limbate capillary seta; e, abdominal short limbate capillary seta; /, posterior abdominal brushlike seta; g, low avicular hook; h, tall, long-necked avicular hook; i, j ,

palmate and avicular hooks, (a-d and g, USNM-W 50636; e, f, and i, USNM-W 50637; h and /,

USNM-W 50638.)

Caobangia ceylonica, new species

FIGURES 9/, 17

MATERIAL EXAMINED.—Ceylon: [1] Mousakande

Group, Gammaduwa [drainage of the Mahaweli

River] (O7°34'N, 80°42'E), from Ganga abbreviata

(Reeve) (USNM-M 574104), coll. H. G. Deignan,

30 May 1944, "3,000 feet [elevation] in rocky pool

of mountain torrent" (USNM-W 50631, holotype;

USNM-W 50632, paratypes), dry material; [2]

Andooloo, Bintenne [drainage of the Walawe

River] (06°24'N, 80°48'E), from Paludomus

hanelyi Dohrn (MCZ 74983), coll. E. L. Layard,

1864 (USNM-W 50633, paratypes), dry material;

from Tanalia aculeala (Gmelin) (USNM-M 103704)

[no specific locality given], coll. F. Stoliczka

(USNM-W 50634, paratypes), dry material.

DESCRIPTION.—The description is based on setal

morphology, since the species is represented only

by dried material. Palmate hooks of the first setiger

have from 5 to 9 teeth in the arcuate series above

the single central fang (Figure 9/, \la,g,h). The

terminal teeth of the series are stouter than the rest,

the dorsalmost being longer than the others, but

the ventralmost is extremely long (up to 4 times

the length of the intermediary teeth). Capillary

setae of both the thorax and the abdomen (Figure

\lb-e) are similar to those of C. indica. The anterior abdominal region may have up to 5 transverse

rows of low avicular hooks, similar to those of all

other species (Figure \lf-h). Long-necked hooks

from the posterior region of the body were not

observed.

REMARKS.—Caobangia ceylonica resembles C.

indica, but differs in having a greater number of
20

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

0.05 mm

FIGURE 17.—Caobangia ceylonica, new species: a, palmate hook from first thoracic setiger; b,

longer limbate capillary seta from second thoracic setiger; c, shorter limbate capillary seta from

same; d, short limbate capillary seta from posterior abdomen; e, posterior abdominal brushlike

seta; /, low avicular hook (a-f, USNM-W 50632); g, adult (left) and juvenile (center) palmate,

and avicular (right) hooks (USNM-W 50633); /(, palmate and avicular hooks (USNM-W 50634).

distal teeth on the palmate hooks and an even

longer ventralmost terminal tooth.

Caobangia ceylonica is known only from Ceylon

and associated only with pleurocerid snails of the

genera Ganga, Paludomns, and Tanalia (Figure

18).

Comparison of Species of Caobangia

Seven species of the genus Caobangia can be

discriminated, based primarily on the morphology

of the palmate hooks of the first setiger. Although

the actual number of teeth in the distal arcuate

series may overlap (Table 1), application of the

"two standard error overlap" rule of thumb (Table

2) suggests no real differences among C. smithi,

C. bmndti, C. ceylonica, and C. morrisoni. When

the data are submitted to t-tests (Table 3), no significant differences (at the 95 percent level) are

present only in the following comparisons: C.

brandti-C. ceylonica; C. brandti-C. smithi; and C.

ceylonica-C. smithi. Were it not for the differing

size and length of the terminal teeth of the arcuate

series, it would be impossible to differentiate among

these three species.

For the most part, the geographic distribution

of the seven species (Figures 18 and 19) indicates

discrete areas for each, whether confined to an

island (C. ceylonica on Ceylon and C. morrisoni

on Java), to neighboring islands (C. abbotti on

islands of the Philippines and on Borneo), or to

specific river systems on the mainland (C. indica

from the Ganges, C. smithi from the Sal ween and

Pegu-Sittang, C. brandti from the Mekong and

Chao Phraya, and C. billeti from the Kiang). The

single exception to this is the case of specimens of C.

smilhi associated with Brotia sp. from Huai Um

Meng (Figure 19), mentioned above. Basically this

species of Caobangia is restricted to the Salween/

Pegu-Sittang drainages; this record places the

species in the upper reaches of the Chao Phraya

system of central Thailand. The most reasonable
NUMBER 175 21

explanation for this occurrence would seem to be

that of "stream capture" or the eastward wandering

of a population of C. smithi during the monsoon

season. Morrison (1954:374) has determined that

the thiarid gastropods are all parthenogenetic and

ovoviviparous. Thus, a single specimen of the

thiarid genus, Brotia, might well make its way between stream heads on either side of a divide and

establish a clonal population in a new drainage

system. The present observations are based upon

relatively few localities, and it is quite possible that

more intensive and/or widespread collections

will uncover other similar cases of drainage

transgression.

TABLE 1.—Frequency distribution of numbers of distal teeth on palmate hooks

of first setigers of species of Caobangia

Numbers

of distal

teeth

4

5

6

7

8

9

10

11

12

13

14

15

C. indica

5

21

18

9

C. smithi

2

19

74

48

18

4

1

C. brandti

31

75

45

11

5

C. ceylonica

5

30

20

9

1

C. morrisoni

5

16

23

7

2

4

1

C. billeti

14

18

9

1

2

1

C. abbotti

2

9

18

41

33

15

8

1

2

TABLE 2.—Summary of material examined and of number of distal teeth of palmate

setae of species of Caobangia

Species

C: indica

C. smithi

C. brandti

C. ceylonica

C. morrisoni

C. billeti

C. abbotti

Number

of

snails

3

9

9

3

3

1

9

Nu m ber

of

localities

3

7

9

3

2

1

8

Number

of hooks

examined

53

166

167

65

58

45

129

Modal

number

of teeth

5

6

6

6

7

8

10

Range of

number

of teeth

4-7

4-10

5-9

5-9

5-11

7-12

7-15

Mean

number

of teeth

5.58

6.46

6.31

6.55

7.02

8.16

10.46

Two

standard

errors

0.22

0.16

0.14

0.22

0.48

0.40

0.38

Mean

± 2 S.E.

5.36-5.80

6.30-6.62

6.17-6.45

6.35-6.75

6.54-7.50

7.76-8.46

10.08-10.84

TABLE 3.—Comparison of t-values (upper right) and their probabilities (lower left)

derived from number of distal teeth of palmate setae of species of Caobangia

c.

c.

c.

c.

c.

c.

c.

Species

indica

smithi

brandti

ceylonica

morrisoni

billeti

abbotti

C. indica

P < 0.001

P < 0.001

P < 0.001

P < 0.001

P<0.00I

P < 0.001

C smithi

11.00

P = 0.10-0.20*

P - 0.50*

p = 0.001-0.01

P < 0.001

P < 0.001

C. brandti

9.57

1.41

P = 0.05-0.10#

P < 0.001

P < 0.001

P<0.001

C. ceylonica

8.68

0.67

1.82

P = 0.01-0.02

P < 0.001

P < 0.001

C. morrisoni

8.38

3.17

3.98

2.50

P < 0.001

P < 0.001

C. billeti

14.73

8.93

9.80

fi.28

4.40

P < 0.001

C. abbotti

37.25

45.82

27.93

33.42

15.49

12.87

• Not significant at 95 percent level.
22

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

A fine potential taxonomic problem at the

specific or subspecific level is posed by the two types

of long-necked avicular hooks of C. abbotti (cf.

Figure 13; from Sabah and Figure 13r from Luzon).

The long-necked hooks are rather difficult to find

in dried material, and adequate numbers of wellpreserved specimens from localities throughout the

Philippines, as well as from other areas on Borneo,

will clarify the situation one way or the other.

Lacking this, there is no choice but to assume that

a single species, C. abbotti, ranges throughout the

Philippines to Sabah and Sarawak.

8(TE

25°N

20°N

15°N

180 K

FIGURE 18.—Southeast Asia, showing localities of various species of Caobangia. Inset is shown in

detail in Figure 19. Small circles in the inset indicate localities only, not individual species.

Numbers accompanying species localities refer to numbers in the "Material Examined" section

of each species account. The unnumbered locality of C. sviilhi is the northernmost "Pegu" (cf.

text footnote 4). (Based on U.S. Navy Hydrographic Office Miscellaneous Chart No. 15,254, 1961.)
NUMBER 175 23

Key to Species of Caobangia

1. One or both terminal teeth of palmate hooks 2 or more times longer than others (Figure

9c,f) 2

Terminal teeth less than 2 times longer than others (Figure 9a,b) 5

2. Terminal teeth equal or subequal in length (Figure 9c) C. morrisoni, new species

Terminal teeth unequal in length 3

3. Longer terminal tooth about twice length of others (Figure 9d) C. smithi, new species

Longer terminal tooth greater than twice length of others 4

4. Longer terminal tooth about 3 times length of others (Figure 9e) C. indie a, new species

Longer terminal tooth about 4 times length of others (Figure 9/) C. ceylonica, new species

5. Modal number of teeth in distal series 6 (Figure 9a) C. brandti, new species

Modal number of teeth in distal series 8 (Figure lla-c) C. billeti

Modal number of teeth in distal series 10 (Figure 96) C. abbotti, new species

°E y'lOO'E \1O2°E/ V ^7

FIGURE 19 Distribution of species of Caobangia in Burma, Thailand, Laos, and North Vietnam. Stippled areas represent drainages of pertinent large river systems (labeled in italics) and

dashed lines show national boundaries. Numbers accompanying species localities refer to numbers in the "Material Examined" section of each species account. The unnumbered locality

of C. smithi is a less likely "Pegu" (cf. text footnote 4), and the unnumbered locality of C.

billeti indicates the location of Cao Bang, the type-locality. (Based on plate 24, volume 1, The

Times Atlas of the World, 1958.)
24 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Morphological Observations

BRANCHIAL CROWN AND SUPPORTING SKELETON

(Figures 20, 21; Plates 6-8: C. brandti; C.

abbotti).—In his original description, Giard (1893:

474) observed that the branchial crown of Caobangia billeti was supported by a hyaline cartilaginous skeleton and that the 24 to 32 or more ciliated tentacles each contained a blood vessel. These

observations have been confirmed for all species of

Caobangia. For the most part, the branchial crowns

of specimens preserved in alcohol are strongly

contracted, and it is difficult to observe details of

their structure. A few specimens of C. abbotti from

Ranau, Sabah, were in a more relaxed condition

and allowed the following observations (Figure

20).

The material comprising the skeleton stains with

aniline blue and the whole is made up of cylindrical units, one to two times as long as broad, each

joined to the next to form the branching linear

structure that is the skeleton (Figure 21, Plates 6,

7). The units have rather thick solid sides and

thinner common ends; each contains small quantities of what is assumed to be cytoplasm as well as

a nucleus (Plate 6b). The skeletal structure conforms to the short description given by Person and

Philpott (1969:5-6) for Eudistylia polymorpha.

There are three pairs of radioles, the two dorsal

pairs (DR, MR) being better developed than the

ventral pair (VR, Figure 20). The former bear bipectinately disposed pinnules and the latter has

far fewer pinnules, which appear to be in a simple

pectinate distribution. There is no palmate membrane connecting the radioles. As noted by Giard

(1893) the radioles and pinnules are ciliated (CE),

and supported by a cartilaginous skeleton (CS)

accompanied by blood vessels (BV, Plate Gc,d).

At the base of the crown the skeletal elements

are united in what might be called a "yoke" (SY),

a U-shaped structure, open ventrally and closed

dorsally (Figure 21, Plate 8/;). Similar crownsupport construction has been observed in histological sections of some four genera of the Sabellidae, i.e., Amphiglena, Euchone, Myxicola, and

three species of Sabella. In contrast to these, how0.2 mm

DR

VR

FIGURE 20—Caobangia abbotti, new species: Branchial crown (USNM-W 50644). (DR = dorsalmost radiole, MR = middle radiole, VR = ventralmost radiole.)
NUMBER 175 25

ever, in Caobangia paired extensions of the cartilaginous skeleton (CSE) project posteriorly from

the yoke and undergo a series of dorsoventral

loopings, passing dorsal to a given setal fascicle;

the extensions finally taper to an end at about the

level of the fourth setiger (Figure 21, Plate la,b).

Fibers of the longitudinal muscles (LM) of this

region are inserted at all points along the length

of these sinuous processes (Plates 6a,b; la,b).

NERVOUS SYSTEM (Plates 6, 7: C. brandti; C.

abbotti).—The available preserved specimens of

Caobangia all proved to be refractory to a number

of histological staining techniques specific for

nervous tissue. The account to follow is based on

observations of sections treated with Mallory's

Triple Stain and is rather incomplete.

The supraoesophageal ganglion (SPG) of

Caobangia lies midway between the base of the

branchial crown and the first thoracic setiger (Plate

lc,d). It is relatively large and is broadly joined,

laterally and ventrally, by thick circumoesophageal

commissures (CG), to a pair of relatively large

masses, the suboesophageal ganglia (SBG), which,

in turn, are joined by a rather thin connective,

about one-fifth the diameter of the suboesophageal

ganglia; the connective passes ventrally to the gut,

just in front of the setal fascicles of the first setiger

(Plate lc,d). Subsequent segmental ganglia (SGG)

are situated ventrolaterally, are connected by very

thin transverse commissures, and come to lie progressively closer to one another (Plate 7c). The

first ganglionic pair posterior to the suboesophageal

ganglia is just behind the first setal fascicle, and

the second and third are ventral to their respective

setal fascicles. Further observations of the ventral

nerve cord were not possible.

The innervation of the branchial crown appears

to arise from a pair of nerves that originate from

each side of the anterior margin of the supraoesophageal ganglion. Each of these pass ventrally, at

the base of the three pairs of radioles, and each of

the radioles receives a pair of nerves (RN) that

lie on each side of its cartilaginous support (Plate

6d).

NEPHRIDIAL DUCTS (Figure 6b; Plates Sb,c; 9,

10: C. abbotti).—Zenkevitch (1925:2-3, et seq.)

proposed two so-called subtribes for the sabellid

polychaetes: the Thoracogoneata and the Abdominogoneata.

The Thoracogoneata were considered to be

sabellids with a pair of thoracic nephridia opening

far anteriorly by a single common duct, with thoracic gonoducts, also opening far anteriorly by a

single common duct, and with neither nephridia

DR

0.2 mm

FIGURE 21 Caobangia brandii, new species: Dorsolateral view of cartilaginous skeleton; part of

the skeleton of the branchial crown is lacking, due to limited clearing of the specimen; the

bases of the right setal fascicles have been omitted. (CSE = extension of cartilaginous skeleton,

DR = right dorsal radiolc, SY = skeletal yoke.)
26 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

nor gonoducts in the abdomen. The contrasting

subtribe, the Abdominogoneata, was characterized

by the possession of a pair of thoracic nephridia

opening far anteriorly by a single common duct

and by the presence of abdominal gonoducts opening from the abdomen by segmental ducts; the

gonoducts, in this case, were considered to be modified abdominal nephridia. It is, perhaps, well to

note that Hartman's (1951:380) interpretation of

Zenkevitch's subtribe is somewhat at variance with

the above.

On the basis of Giard's (1893) description,

Zenkevitch (1925) placed Caobangia in the Thoracogoneata, along with the genera Amphicorina

[ = }Oriopsis~\, Oria [ = Oriopsis~\, Fabricia, and

Manayunkia; it is difficult to see how he arrived

at this conclusion, in view of the sketchiness of

Giard's description.

The nephridial system of Caobangia consists of

one pair of ducts (AN, DN, Figure 6b, Plates 9, 10),

each with two nephrostomes (NST 1, 2) in the

coelomic cavity between the base of the branchial

crown and the first setiger. The anterior nephrostome (NST 1) merges into the descending nephridial duct (DN) ventral to the cartilaginous extension from the yoke supporting the branchial crown.

The second nephrostome (NST 2) joins directly

with the same duct approximately 100 microns

posterior to the first, between the cartilaginous

extension and the gut. The paired descending

nephridial ducts then move medially, ventral to

the gut, then straight back to about the level of

the transverse rows of abdominal avicular hooks,

where they bend upon themselves and continue

anteriorly, still ventral to the gut and medial to the

descending nephridial canals, as paired ascending

ducts (AN), to about the level of the fourth setiger

where they join to form a single duct. At about the

level of the nephrostomes, the single ascending

duct splits, each branch moving laterally under the

gut, then dorsally around the gut, over the dorsal

surface of the skeletal yoke, uniting once again in

the midline, dorsal to the gut. The united duct

finally opens to the exterior as a nephridiopore

within the area surrounded by the branchial crown

(NPR, Figure 6b, Plate 86), dorsal to the mouth

opening. The descending nephridial ducts tend to

have somewhat thinner walls than the ascending

ducts. With one exception, the cell membranes

of the tissue of the duct walls are obscure: at about

the level of the sixth thoracic setiger, the walls of

the ascending ducts (AN) are composed of columnar cells (Plate 106). Because of the general compression of the ducts, it was not possible to observe

the presence of cilia in the lumen, except in the

initial portions of the descending ducts (DN) near

the nephrostomes (Plate 9a,b). These observations

do not agree with the findings of Koechlin (1959,

1961) in the case of Sabella pavonina, for there are

no large, voluminous regions in the nephridial

canal of Caobangia, there are no histologically welldefined sections along its length, and there appears

to be a more intimate association of blood vessels

with the nephridial canal of the freshwater worms.

REPRODUCTIVE SYSTEMS (Figure 66; Plates 1-6, 8,

10, 11: C. brandti; C. abbotti). —Giard (1893:476)

noted that although he was unable to distinguish

testes, since all specimens available to him were

ovigerous, he was convinced that C. billeti was hermaphroditic. Giard also observed that the ovary

was located in the loop of the gut and, on the basis

of Billet's having seen well-developed larvae moving about in the Caobangia burrows, Giard suggested that an incubative chamber was formed by

the external body surface of the adults, perhaps

from the development of an area similar to the

posterior ventral flattened area of Euchone.

Extensive regions of sperm and egg formation

are to be found in specimens of Caobangia. There

seems to be no special orientation of maturation

of either spermatocytes or oocytes, and mature and

developing eggs or sperm both appear to be mixed,

but in reasonably discrete areas which might be

called an "ovary" (O) and "testis" (T), respectively. Both appear to be rather flattened unpaired

structures, extending from one side of the coelom

to the other and from about the level of the transverse rows of avicular hooks to near the basal end

(Plates be, lla). The "ovary" is dorsal to the

"testis" and is closely applied to the ventral surface

of the enlarged stomachic cavity of the gut, then

to the ventral surface of the gut as it emerges from

the stomachic region, and later as it moves beneath

the posterior curve of the body. The "testis," in its

turn, is closely applied to the ventral surface of the

"ovary." At about the level of the transverse rows

of avicular hooks the "testis" forms a pair of rather

short ducts (TD) which lead to the body surface

and open to the exterior (TO), adjacent to the

ridge formed by the ascending gut (Figure 66,
NUMBER 175 27

Plate \\c,d). At the margins of this ridge there are

rather deep ciliated grooves (SG) which continue

forward, along the ascending gut in its lateral and

dorsal course to the dorsal surface of the body

(Plates 2, Sa,b; 10c,d; \\c,d). At the level of the

anal opening the ciliated grooves are lost in a pair

of broad ciliated fields (LCF) on the dorsal surface, which ultimately merge with cilia on the floor

of the inner surface of the branchial crown (Plate

\b,d). Although no sperm have been observed in

the ciliated grooves, the short testicular ducts (TD)

leading to them from the "testis" are filled with

sperm (Plate \\c,d).

Ventral and lateral to the "ovary" and "testis"

there is a pair of rather large ducts (LD) which,

when not occupied, has thick walls (Plates 3d, 4b).

The walls are capable of considerable extension

for, at several levels, more posteriorly, developing

embryos and larvae occupy their cavities (Plates

4d, 5b,d). The posterior ends of the ducts seem to

be blind, but the anterior ends (LDO) open to the

exterior, slightly in back of the openings of the

ducts from the "testis" (TO, Figure 66). Masses

of yolk granules (YG) also are found in these ducts,

as well as free in the coelomic cavity (Plates 4c,

5a,c; lie). No specific site of yolk formation has

been recognized. Further, no passageway has been

observed between the ovary and the larval ducts,

although such must exist.

It was mentioned above that the ducts from the

"testis" have been observed to be filled with sperm.

It should be noted that a second pair of short

sperm-filled ducts (SD) can be seen in sections

from the region of the floor of the branchial crown

(Figure 6b, Plate 8a). These ducts open externally

among the cilia at the margin of the mouth; internally they open directly into the coelomic cavity

in the vicinity of the skeletal yoke and the supraoesophageal ganglion. No sperm have been observed

free in the coelomic cavity. The source and destination of the sperm in these ducts are not known.

It is possible that sperm from the "testis," after

traversing the ciliated groove lying alongside the

ascending gut, are moved to the floor of the branchial crown on ciliated fields on the dorsal surface,

pass into the ducts, and then move posteriorly,

internally, to fertilize ova of the same individual.

It is also possible that sperm from a second individual are collected on the branchial crown, passed

down the ciliary tracts of the pinnules and radioles

to the floor of the crown, and then selectively sorted

and deposited in the ducts, through which they pass

to fertilize the ova at the posterior end. The latter

would seem to be the more reasonable alternative.

Apart from the internal opening to the coelom,

these structures bear a resemblance to the seminal

receptacles of Manayunkia baicalensis, described

by Zenkevitch (1925:18-20).

LARVAL MORPHOLOGY (Figures 22-25: C. brandti;

C. abbotti).—Larvae of Caobangia can be dissected

quite readily from the adult body. In the case of

the two species from which larvae have been obtained, Caobangia brandli (Figure 22) and C.

abbotti (Figure 24), larvae are from 0.60 to 0.95

mm in length and about 0.20 mm wide. They are

provided with eyes (EY) in the form of pigment

cups with lenses, and with the rudiments of a cartilaginous skeleton (DCS). They have an extensive

pattern of ciliation which includes an anterior prototroch, a ventral neurotroch, a posterior telotroch,

as well as anterior and posterior tufts of cilia and

transverse bands of cilia (CB) which extend dorsally from the neurotroch between successive setal

fascicles. At this stage there is a central core of yolk

(YG) but no sign of either mouth or anus (Figure

24).

Segmentation is indicated by seven pairs of fascicles of two setae each (LLC and SLC). Apart from

size, the setae are quite comparable to the adult

thoracic setae, i.e., one is a longer limbate capillary

seta and the other is a shorter limbate capillary seta

(Figures 25b,c; 25b,c). In both species, there is an

additional type of seta which has no counterpart

in adults. Near the posterior end there are two

palmate hooks (LPH) on each side on the dorsal

surface (Figures 22, 2Se, 24a, 25e,f). They are similar to the palmate hooks of the first thoracic setiger

of adults but lack central fangs. This would not

appear to be due to the small size of these emergent

posterior hooks, for embedded developing palmate

hooks with a central fang (DPH) can be seen

within the body in their usual anterior position,

associated with, and ventral to the first setal fascicle

(Figures 23«, 24a, 25a). Another point of difference

between the posterior palmate hooks of the larvae

and the fanged palmate hooks of the adult lies in

their individual orientation. Where the adult hooks

are disposed such that the teeth of the arcuate

series point away from the branchial crown, the

larval posterior palmate hooks point toward the
28 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

head end. The only other type of emergent seta

may be the early counterpart of the adult brushlike abdominal seta (BLS, Figures 24, 25d). In

addition to the palmate hooks of the first setiger,

two other types of setae can be seen developing

beneath the body surface. In the posterior region,

up to six embedded low avicular hooks (DAH)

are found just anterior to the posterior larval palmate hooks, and one or two embedded tall, longnecked avicular hooks (DTH) just posterior to

them (Figures 22, 23d,/; 24a). From the distribution of the various types of setae, it would appear

that the seven thoracic setigers of the adult arise

from the seven larval setigers provided with the

longer and shorter limbate capillary setae. It

appears also that the posterior larval palmate

hooks are adaptations for larval movement prior

to encapsulation and metamorphosis, and that the

point of linear elongation, corresponding to the

pygidium of other polychaetes, lies in the region of

the posterior palmate hooks of the larvae, between

the developing low hooks and tall, long-necked

avicular hooks.

LARVAL SETTLING AND METAMORPHOSIS.—It has

been reported earlier (Jones, 1969:833-834) that

liberated larvae of Caobangia settle on the periostracum of a given snail shell or upon bare calcium

carbonate. The settled larvae then form a domeshaped capsule over themselves and coil within

it with their posterior end in the center. As a larva

grows, the posterior end either penetrates the cap

0.05 mm

FIGURE 22.—Caobangia brandti, new species: Dorsal view of

larva; cilia and yolk omitted. (DAH = embedded developing

low avicular hooks, DTH = embedded tall avicular hook,

LPH = larval palmate hooks.)

FIGURE 23.—Caobangia brandti, new species, larval setae: a,

embedded palmate hook from first setiger; /;, longer limbate

capillary seta; c, shorter limbate capillary seta; d, embedded

low avicular hook (foreshortened); e, larval palmate hooks

from posterior region; /, embedded tall, long-necked avicular

hook (slightly foreshortened).
NUMBER 175 29

sular floor or continually forms capsular material

as it moves through the underlying periostracal

layer and the carbonate matrix of the snail shell.

Growth in length and girth, along with the dissolution of carbonate and the laying down of a

burrow lining, result in the formation of the adult

burrow. Whole mounts of such developing worms

demonstrate that it is during this period of growth

that a diverticulum arises from the posterior end

of the developing gut. This diverticulum, during

the course of its linear growth, undergoes a looping,

and then movement, internal to and within the

body wall, anteriorly. This anterior growth proceeds

along the ventral surface to a point just anterior

to the first row of abdominal low avicular hooks,

then shifts dorsally (almost invariably on the right

FIGURK 24.—Caobangia abhotti, new species: a, dorsal view of larva; b, ventral view of another

larva. (BLS = brushlikc seta, CB = ciliated band, DAH = embedded developing low avicular

hooks, DBC = developing buds of branchial crown, DCS = developing cartilaginous skeleton,

DPH = embedded developing palmate hook, DIH = embedded developing tall avicular hook,

EY = eye, GA = granular aggregations, LLC = longer limbate capillaty seta, I.Nf = longitudinal muscles, LPH = larval palmate hooks, SLC = shorter limbate capillary seta, YG = area

of remaining yolk granules.)
30 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

side), and continues on the dorsal surface to the

level of the second to fourth thoracic setigers where

growth stops and the anal opening is established.

It was assumed that larval liberation was accomplished by the bursting of the adult body wall

(Jones, 1969:833-834), but with the discovery of

the larval ducts (LD) and their external openings

(LDO), it is now felt that egress is through a "birth

pore" (Figure 6a,b).

Observations have been made on two juvenile

specimens of C. abbotti which had encapsulated on

the periostracum of a snail shell, undergone linear

growth, and had grown backward into a continually

enlarged burrow in the calcium carbonate of the

snail shell. In both cases the branchial crown was

developed, the anal opening was at the third or

fourth setiger, and there was a single row of emergent low avicular hooks in the abdominal region.

One specimen (0.98 mm length; 0.12 mm wide at

widest part, at the level of the low avicular hooks;

0.08 mm at first setiger) was provided with a palmate hook, a longer and a shorter limbate capillary

seta on each side of the first setiger; the second to

seventh setigers all had a longer and a shorter limbate capillary seta in each fascicle; there were eight

low avicular hooks in each of the single rows, accompanied by a single brushlike seta; and there

was a single, tall, long-necked avicular hook on

each side. All of these were emergent.

The second juvenile (1.14 mm length; 0.19 mm

wide at the level of the low avicular hooks; 0.08 mm

at the first setiger) had two palmate hooks on one

side of the first setiger and three on the other,

0.05 mm

FIGURE 25.—Caobangia abbotti, new species, larval setae: a,

embedded palmate hook from first setiger; b, longer limbate

capillary seta; c, shorter limbate capillary seta; d, brushlike

seta from posterior region; e, f, larval palmate hooks from

posterior region.

accompanied in both cases by two longer and one

shorter limbate capillary setae; the second setiger

had three longer and three shorter limbate capillary setae; the third setiger, three longer and one

shorter; the fourth to seventh setigers each had a

longer and a shorter limbate capillary seta in each

fascicle; and the single rows of low avicular hooks,

each accompanied by a single brushlike seta, had

11 on one side and 13 on the other. No tall, longnecked avicular hooks were observed.

The Taxonomic Status of Caobangia

Classically the Sabellidae have been characterized

as having two body regions: the thorax, composed

of relatively few segments, the first of which is provided with limbate capillary notosetae only, and

the remainder with similar notosetae, as well as

neurosetal avicular or long-handled hooks; and the

abdomen, from a few to many segments, each provided with notosetal hooks and neurosetal limbate

capillaries.

Rioja (1923) recognized three subfamilies of the

Sabellidae: Sabellinae, with thoracic hooks avicular

or with a prolonged base, with or without pickaxe

setae, with an obvious faecal groove, and welldeveloped ventral scutes; Fabriciinae, with longhandled thoracic hooks; and Myxicolinae, with

branchial filaments united all along their length,

and abdominal hooks disposed in a nearly complete

circle around the body.

Johansson (1927), on the other hand, recognized

two subfamilies: Sabellinae, with "short stemmed"

hooks in both the thorax and the abdomen, with

longitudinal muscles which are not "nematoid,"

with innervation of the branchial crown by a single

pair of nerves, and lacking a so-called ciliated

organ; and Fabriciinae (including Myxicola), with

a few "long-stemmed" hooks in the thorax, with

longitudinal muscles of the body usually "nematoid," with the branchial crown innervated by

"double" nerves, and with a ciliated organ associated with the supraoesophageal ganglion.

As mentioned above, Zenkevitch (1925) proposed

two "subtribes" for the Sabellidae: Abdominogoneata, with abdominal nephridia modified as

gonoducts opening from their respective abdominal

segments; and Thoracogoneata, with gonoducts

opening far forward, in the vicinity of the branchial crown. Hartman (1951) has considered the
NUMBER 175 31

Abdominogoneata to be equivalent to the Sabellinae and the Thoracogoneata to be equivalent to

the Fabriciinae; she begs the question of where to

place Myxicola, which Zenkevitch put among the

Abdominogoneata.

Present-day usage may recognize Rioja's three

subfamilies (Fauvel, 1927; Hartman, 1959; Uschakov, 1965) or Johansson's two subfamilies (Day,

1967); Zenkevitch's two subtribes are not utilized

at all.

In his original description, Giard (1893:474)

stated that the characters of Cnobangia billeti were

different enough to justify the erection of a new

genus and "even probably a distinct family"

("meme sans dome une famille distincte"). However, this observation was not followed up and

Caobnngia subsequently has been considered a

curious sabellid. The only other gesture toward

separating the genus from other sabellids was that

of Ghamberlin (1919:470) where he names Caobangiiniae [sic] as a new subfamily in a dichotomous

key. Ghamberlin's usage has not been followed by

subsequent workers, and, where considered at all,

Caobangia has been placed with the Fabriciinae.

All seven species of Caobangia possess a number

of morphological characters unique to the genus

which justify the relegation of it to a new family,

the Caobangiidae, the type-genus of which is here

designated to be Caobangia Giard, 1893.

These morphological characters are: (1) the

presence of neurosetal palmate hooks on the first

setiger; (2) the absence of hooks of any sort on the

following thoracic setigers; (3) the presence of

two types of avicular hooks in the posterior region;

and (4) the recurving of the gut within the body

such that the anus opens far anteriorly. It is admitted that the presence of an anterior anus, as

well as the internal development of larvae and the

ability to form burrows in calcium carbonate may

be better considered as adaptations to life in a freshwater environment, in association with molluscs.

Another argument in favor of erecting a separate

family for Caobangia is concerned with the placement of the male and female gonadal openings.

There is a single pair of openings from the "testis"

and another single pair from the larval duct (as

contrasts with a number of segmentally arranged

gonoducts in Zenkevitch's Abdominogoneata, including Myxicola), and these paired openings are

found at the anterior end of the abdomen (in contrast to the Thoracogoneata where a single duct,

in the case of males, opens far anteriorly).

Finally, the presence of two pairs of nephrostomes associated with a pair of nephridial canals

may also be considered to be a familial character.

General Comments on Caobangia

CONCERNING MOLLUSCAN ASSOCIATES.—It is of

some interest that the easternmost species of Caobangia, C. abbotti (Figure 18), has been found in

association with four genera of thiarid snails in the

Philippines (including Brotia) and with one

thiarid, Brotia, on the island of Borneo. Further,

C. morrisoni, the southernmost species, from Java,

and C. billeti, from North Vietnam, are both associated with Brotia. To the west, C. ceylonica is

associated with three pleurocerid genera. To the

northwest, C. indica has been found in the shells

of one pleurocerid and one thiarid (not Brotia);

the same is true of C. smithi, the adjacent species

to the east, but the thiarid is Brotia. At the apparent center of the known distribution of Caobangia

is C. brandti (Figure 19), which in northern Thailand and Laos occurs with a single thiarid (Brotia),

three viviparid genera, and one unionid bivalve.

Although it may be the fortuitous result of an

inadequate search through various museum collections, it would seem that the one gastropod common to six of the seven Caobangia species is the

thiarid, Brotia. Similar to other thiarids, Brotia

has a reproductive pattern of ovoviviparous parthogenicity (Morrison, 1954:374) and a brood pouch

which may be ". . . very large, crowded with a great

many relatively small young of uniform size" (Morrison, 1954:383). Morrison (1954:374) also has

noted that these characteristics and the consequent

ability to form clonal populations if a single snail

reaches a new freshwater locality, either by stream

capture or by adventitious transportation, account

for the widespread distribution of the Thiaridae.

CONCERNING THE HABITAT OF MOLLUSCAN ASSOCIATES.—The lew ecological notes accompanying the

various molluscs considered in this work suggest

that the molluscs, and the associated Caobangia,

occur at medium elevations, from 800 to 1300 m.

Further, most occur in fast-moving water [Bafanocochlis glons, with C. abbotti; Brotia cf. baccata,

with C. smithi; Ganga abbreviata, with C. cryionica;

and Brotia pseudosnlco.spira pseitdosulcospira and
32 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

B. p. armata (Brandt, 1968:275)], although one,

Mekongia jullieni, with C. brandti, was reported

from a sand bank (Brandt and Temcharoen, 1971:

116) and Brotia binodosa subgloriosa was found

"on sandy grounds .. . at comparatively quiet parts

. . . but at Ban Palo it is also found in rapids"

(Brandt, 1968:270).

It was noted earlier (Jones, 1969:834) that Caobangia brandti was found in so-called dead valves

of the bivalve Hyriopsis delaportei. This suggested

that it was possible that limestone outcrops along

river or stream banks might serve as populational

reservoirs which would allow the "infection" of new

molluscs at that site, thus overcoming the continual

down-river attrition of newly emerged larvae. It is

interesting that Billet (1896-98:64) mentions such

"rochers calcaires" in the vicinity of Cao Bang.

SOME BASIC QUESTIONS POSED BY Caobangia.—

1. What is the mechanism that mediates the internal anterior growth of the ascending gut such that

it grows straight, beneath the ventral surface, moves

dorsally on the right side, then straight to the midthoracic region?

2. Where is the usual prepygidial growth zone of

other polychaetes? Is the caobangiid growth zone

just posterior to the posteriormost row of low avicular hooks, or elsewhere?

3. If the caobangiids are not self-fertilizing hermaphrodites, how are sperm from one worm transferred to another? Are chemotactic behaviorisms

implicated or are transfers merely fortuitous, depending on the vagaries of water currents? What is

the source and fate of the sperm observed in the

short anterior ducts?

4. Since Caobangia burrows are lined with an intact secreted membrane, and the various setae

seem not to be unduly worn, how is enlargement

of a given burrow accomplished?

Literature Cited

Banse, Karl

1957. Die Gattungen Oriopsis, Desdemona und Augeneriella (Sabellidae, Polychaeta). Videnskabelige

Meddelelser fra Dansk Naturhistorisk Forening,

119:67-105, 9 figures.

Billet, Albert

1896-98. Deux Ans dans le Haut-Tonkin (Region de

Cao-Bang). Bulletin scientifique de la France et de

la Belgique, 28:1-254, 21 figures, 11 plates.

Brandt, Rolf A. M.

1968. Description of New Non-Marine Mollusks from

Asia. Archiv fur Molluskenkunde, 98:213-288, 41

figures, 3 plates.

Brandt, Rolf A. M., and Prasong Temcharoen.

1971. The Molluscan Fauna of the Mekong at the Foci

of Schistosomiasis in South Laos and Cambodia.

Ibid., 101:111-140, 20 figures.

Bush, Katherine J.

1904. Tubicolous Annelids of the Tribes Sabellides and

Serpulides from the Pacific Ocean. Pages 167-346

in volume 12 of Merriam, ed., Harriman Alaska

Expedition. 24 plates. New York: Doubleday, Page

& Company.

Chamberlin, R. V.

1919. The Annelida Polychaeta. Memoirs of the Museum

of Comparative Zoology at Harvard College, 48:

1-514, 80 plates.

Dawydoff, C.

1959. "Ontogenese des Annelides." Pages 594-686 in

volume 5 of Grasse, ed., Traite de Zoologie, Paris:

Masson.

Day, J. H.

1967. A Monograph of the Polychaeta of Southern Africa,

part 2: Sedentaria. Pages 459-878, 90 figures. London: Trustees, British Museum (Natural History).

Deignan, H. G.

1945. The Birds of Northern Thailand. United States National Museum Bulletin, 186:1-616, 9 plates, 4 maps.

Fauvel, P.

1927. Polychetes se'dentaires, Addenda aux Errantes,

Archiannelides, Myzosto'maires. Volume 16 of Faune

de France. Paris: Lechevalier.

Fischer, Henri

1898. Notes sur la Faune du Haut-Tonkin, III: Liste des

Mollusques Recueillis par le Dr. A. Billet. Bulletin

scientifique de la France et de la Belgique, 28:310-

338, 4 figures, 2 plates.

Giard, Alfred

1893. Sur un Type nouveau et aberrant de la Famille des

Sabellides (Caobangia Billeti). Comptes Rendus

Hebdomadaires des Seances et Memoires de la Socie'te de Biologie, Paris, 45:473-476.

Hartman, Olga

1951. Fabricinae (Feather-duster Polychaetous Annelids)

in the Pacific. Pacific Science, 5:379-391, 1 plate.

1959. Catalogue of the Polychaetous Annelids of the

World. Allan Hancock Foundation Publications,

Occasional Paper, 23: 628 pages.

Johansson, K. E.

1927. Beitrage zur Kenntnis der Polychaeten-Familien

Hermellidae, Sabellidae und Serpulidae. Zoologiska

Bidrag fran Uppsala, 11:1-185, 15 figures, 5 plates.
NUMBER 175

Jones, Meredith L.

1969. Boring of Shell by Caobangia in Freshwater Snails

of Southeast Asia. American Zoologist, 9:829-835, 8

figures.

Koechlin, Noemi

1959. £tudc et Reconstruction graphique des Nephridies

de Sabella pavonina Savigny (Annelide Polychete).

Comptes Rendus des Seances de VAcademic des

Sciences (Paris), 248:2385-2387, 2 figures.

1961. Etude anatomique et histologique des Nephridies

de Sabella pavonina (Sav.) Annelide Polychete.

Bulletin de la Laboratoire Maritime de Dinard,

46:4-35, 14 figures, 1 plate.

Lamy, Edouard, and Marc Andre

1936. Annclidcs Perforant les Coquilles de Mollusques.

Comptes Rendus, XII* Congres international de

Zoologie, I.isbonne, 2:946-968, 6 figures.

Mclntosh, W. C.

1922. Polychaeta—Hermellidae to Sabellidac. Page 222 in

Part 1 in Volume 4 of A Monograph of the British

Marine Annelids. London: The Ray Society.

Mesnil, F.

1901a. Remarques sur les Polychetes d'eau douce, a

Propos des Formes Nouvelles du lac Baikal. Comptes

Rendus des Seances de la Socie'te de Biologie, Paris,

53:271-273.

1901b. A Propos des Polychetes d'eau douce, Note rectificative. Biologisches Centralblatt, Leipzig, 21:432.

Monro, C. C. A.

1939. On a Collection of Polychaeta from Near the

Mouth of the River Congo. Revue de Zoologie et

de Botanique Africaines, 32:213-225, 5 figures.

Morrison, Joseph P. E.

1954. The Relationships of Old and New World

Melanians. Proceedings of the United States National Museum, 103:357-394, 1 plate.

National Intelligence Survey

1952. Gazetteer, India (Preliminary): Official Standard

Names Approved by the U. S. Board on Geographic

Names. 787 pages. Washington, D.C.: Office of

Geography, Department of the Interior, Coordinated by the Central Intelligence Agency.

1953. Gazetteer, Philippines (Preliminary): Official Standard Names Approved by the U. S. Board on Geographic Names. 1303 pages. Washington, D.C.:

Office of Geography, Department of the Interior,

Coordinated by the Central Intelligence Agency.

1962. Gazetteer, Pakistan: Official Standard Names Approved by the U. S. Board on Geographic Names.

883 pages. Washington, D.C.: Office of Geography,

Department of the Interior, Coordinated by the

Central Intelligence Agency.

1964. Gazetteer, North Vietnam: Official Standard Names

Approved by the U. S. Board on Geographic Names.

311 pages. Washington, D.C.: Office of Geography,

Department of the Interior, Coordinated by the

Central Intelligence Agency.

1966a. Gazetteer, Burma: Official Standard Names Approved by the U. S. Board on Geographic Names.

725 pages. Washington, D.C.: Office of Geography,

Department of the Interior, Coordinated by the

Central Intelligence Agency.

1966b. Gazetteer, Thailand: Official Standard Names Approved by the U. S. Board of Geographic Names.

675 pages. Washington, D.C.: Office of Geography,

Department of the Interior, Coordinated by the

Central Intelligence Agency.

1968. Gazetteer, Indonesia: Official Standard Names Approved by the U. S. Board of Geographic Names.

901 pages. Washington, D.C.: Office of Geography,

Department of the Interior, Coordinated by the

Central Intelligence Agency.

Nusbaum, J.

1901. Noch ein Wort iiber Dybowscella baicalensis mihi

und einige andere Siisswasserpolychaeten. Biologisches Centralblatt, Leipzig, 21:270-273.

Person, Philip, and Delbert E. Philpott

1969. The Nature and Significance of Invertebrate Cartilages. Biological Reviews, 44:1-16.

Rioja, E.

1923. Estudio sistematico de las Especies Ibericas del

Suborden Sabelliformia. Trabajos del Museo Nacional de Ciencias Natttrales, Serie Zoologica, 48:

1-144, 262 figures.

Smith, H. M.

1945. The Fresh-water Fishes of Siam, or Thailand.

United States National Museum Bulletin 188:1-622,

107 figures, 9 plates.

Uschakov, P. V.

1965. Polychaeta of the Far Eastern Seas of the U.S.S.R.

Translated by Jean Salkind. Edited by Rae Finesilver. Jerusalem: Israel Program for Scientific

Translations.

War Department

1944. Gazetteer to Maps of Burma: Compiled by the

United States Board on Geographic Names. 806

pages. Army Map Service, Corps of Engineers, U.S.

Army.

Wesenberg-Lund, Elise

1958. Lesser Antillean Polychaetes, Chiefly from Brackish

Water, with a Survey and a Bibliography of Fresh

and Brackish-Water Polychaetes. Studies on the

Fauna of Curacao and Other Caribbean Islands,

8:1-41, 15 figures.

Zenkevitch, L. A.

1925. Biologic, Anatomie und Systematik dcr Siisswasserpolychaten des Baikalsees. Zoologische Jahrbiicher,

Abteilung fur Systematik, Geographie und Biologie

der Tiere, 50:1-60, 27 figures, 1 plate.
3 4 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

PLATE 1

Caobangia abbotti, new species: Transverse sections, five microns, Mallory's Triple Stain

(USNM-W 50660); longitudinal locations indicated on Figure 6a: a, b, at 1; c, d, at 2; scale

lines for a, c, 100 microns and for b, d, 50 microns.

a. Section at base of branchial crown.

b. Same section as a, more highly magnified, centered on descending gut.

c. Section just behind anal opening.

d. Same section as c, more highly magnified, centered between descending and ascending gut.

(AG = ascending gut, AN = ascending nephridial duct, BV = blood vessel, cs = cartilaginous

skeleton, DC = descending gut, DN = descending nephridial duct, GA = granular aggregations,

LCF = longitudinal ciliated field, LM = longitudinal muscle, SD = sperm duct, SF 3 = third

thoracic setal fascicle, VNC = ventral nerve cord(s).)
NUMBER 175 35

a

VNC

i%( vtwr
3 6 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

PLATE 2

Caobangia abbotti, new species: Transverse sections, five microns, Mallory's Triple Stain

(USNM-W 50660); longitudinal locations indicated on Figure 6a: a, b, at 3; c, d, at 4; scale

lines for a, c, 100 microns and for b, d, 50 microns.

a. Section between thoracic setigers 5 and 6.

b. Same section as a, more highly magnified, centered between descending and ascending gut.

c. Section near thoracic setiger 7.

d. Same section as c, more highly magnified, centered between descending and ascending gut.

(AC = ascending gut, BV = blood vessel, BVS = blood vessel/sinus associated with descending

gut, DG = descending gut, CA = granular aggregations, LM = longitudinal muscle, ND =

nephridial ducts, SF 7 = seventh thoracic setal fascicle, sc = sperm groove.)
NUMBER 175 37

a

SF 7
3 8 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

PLATE 3

Caobangia abbotti, new species: Transverse sections, five microns, Mallory's Triple Stain

(USNM-W 50660); longitudinal locations indicated on Figure 6a: a, b, at 5; c, d, at 6; scale lines

for a, c, 100 microns and for b, d, 50 microns.

a. Section approximately at the level of first row of low avicular hooks.

b. Same section as a, more highly magnified, centered between stomachic chamber and ascending

gut.

c. Section midway along length of stomachic chamber.

d. Same section as c, more highly magnified, centered between stomachic chamber and ascending

gut.

(AG = ascending gut, AN = ascending nephridial duct, BV = blood vessel, BVS = blood vessel/

sinus associated with descending gut, DN = descending nephridial duct, LD = larval duct, ND =

nephridial ducts, ocr = oocytes, sc = stomachic chamber of descending gut, sc = sperm groove,

YC = yolk granules.)
NUMBER 175 39

a
40 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

PLATE 4

Caobangia abbotti, new species: Transverse sections, five microns, Mallory's Triple Stain

(USNM-W 50660); longitudinal locations indicated on Figure 6a: a, b, at 7; c, d, at 8; scale lines

for a, c, 100 microns and for b, d, 50 microns.

a. Section through posterior fourth of stomachic chamber of descending gut.

b. Same section as a, more highly magnified, centered between stomachic chamber and ascending

gut.

c. Section through more posterior region of stomachic chamber.

d. Same section as c, more highly magnified, centered between stomachic chamber and ascending

gut.

(AG = ascending gut, i. = larva, LD = larval duct, ocr = oocytes, sc = stomachic chamber of

the descending gut, scr = spermatocytes, SFA = abdominal setal fascicle, YG = yolk granules.)
NUMBER 175 41

a

OCT

SFA
4 2 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

PLATE 5

Caobangia abbotti, new species: Transverse sections, five microns, Mallory's Triple Stain

(USNM-W 50660); longitudinal locations indicated on Figure 6a: a, b, at 9; c, d, at 10; scale

lines for a, c, 100 microns and for b, d, 50 microns.

a. Section through posterior loops of gut.

b. Same section as a, more highly magnified, centered near ascending gut.

c. Section through region posterior to loops of gut.

d. Same section as c, more highly magnified, centered near ascending gut.

(AC = ascending gut, BLS = brushlikc seta, DC = descending gut, L = larva, LD = larval duct,

LG = loops of gut, o = "ovary," ov = egg, OCT = oocyte, SCT = spermatocytes, SFA = abdominal

setal fascicle, T = "testis," YC = yolk granules.)
NUMBE

R 175

43

SCT

v

' i
44 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

PLATE 6

Caobangia brandti, new species: Parasagittal sections, seven microns, Mallory's Triple Stain

(USNM-VV 50630); scale lines for a and b, 50 and 10 microns, respectively.

a. Section through base of dorsal radiolc showing relationship of dorsal surface epithelium

(right), cartilaginous skeleton, and ciliated epithelium of inner surface of branchial crown

(left).

b. Same section as a, but more highly magnified, showing detail of cartilaginous skeleton.

Caobangia abbotti, new species: Transverse sections, five microns, Mallory's Triple Stain

(USNM-W 50660); scale lines for c and d arc 10 microns.

c. Section of vcntralmost radioles, showing relationship of radiole to its pinnules.

d. Section of right dorsalmost and middle radioles at base of branchial crown.

(BV = blood vessel, CE = ciliated epithelium, cs = cartilaginous skeleton, LM = longitudinal

muscle, LVR = left vcntralmost radiolc, MR = middle radiole, RDR = right dorsalmost radiolc,

RN = radiolar nerve, SE = surface epithelium.)
NUMBER 175 45
4 6 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

PLATE 7

Caobangia brandti, new species: Parasagittal sections, seven microns, Mallory's Triple Stain

(USNM-W 50630); dorsal to the right, branchial crown above; scale lines for a, c, and d, 100

microns and for b, 50 microns.

a. Section showing cartilaginous extension from skeletal yoke.

b. Section showing relationship of sctal fascicles to cartilaginous extension.

c. Section showing elements of the nervous system.

d. Nearly sagittal section of the region just behind the branchial crown.

(cc = circumoesophageal commissure, CSK = extension of cartilaginous skeleton, DT. = descending gut, LM = longitudinal muscle, MO = mouth region, ND = ncphridial ducts, RN = radiolar

nerve, SBG = subocsophagcal ganglion, SF 1-3 = first to third thoracic sctal fascicles, sec =

segmental ganglia, si>c = supraoesophageal ganglion, SY = skeletal yoke.)
NUMBER 175 47
4 8 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

PLATE 8

Caobangia abbolti, new species: Transverse sections, five microns, Mallory's Triple Stain

(USNM-W 50660); longitudinal locations of b, c, and d indicated on Figure 6b, N 1, N %, and

N 3, respectively; scale lines are 50 microns.

a. Section at level of sperm ducts, 10 microns behind that shown in Plate lfl.

b. Section at level of skeletal yoke, 40 microns behind that of a, above.

c. Section through first ncphrostome of descending nephridial duct.

d. Section through second nephrostome of descending nephridial duct.

(AN = ascending nephridial duct, BV = blood vessel, ix; = descending gut, GA = granular

aggregations, I.CF = longitudinal ciliated field, LM = longitudinal muscle, NPR = ascending

nephridial duct just prior to nephridiopore, NST 1 and 2 = first and second nephrostome of

descending nephridial duct, SD = sperm duct, SY = skeletal yoke.)
NUMBER 175 49
5 0 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

PLATE 9

Caobangia abbotti, new species: Transverse sections, five microns, Mallory's Triple Stain

(USNM-W 50660); longitudinal locations of a, b, c, and d indicated on Figure 6b, N 4, N 5,

N 6, and N 7, respectively; scale lines are 50 microns.

a. Section at about the level of first thoracic setiger.

b. Section just before splitting of ascending nephridial duct.

c. More posterior section.

d. Section between third and fourth thoracic setal fascicles, showing close association of ascending and descending nephridial ducts.

(AN = ascending nephridial duct, cs = cartilaginous skeleton, vx. = descending gut, DN =

descending nephridial duct, r.A = granular aggregations, LCF = longitudinal ciliated field,

LM = longitudinal muscle, SF 4 = fourth thoracic setal fascicle.)
NUMBER 175 51
52 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

PLATE 10

Caobangia abbotli, new species: Transverse sections, five microns, Mallory's Triple Stain

(USNM-W 50660); longitudinal locations of a, b, c, and d indicated on Figure 6b, N 8, N 9,

N 10, and N 11, respectively; scale lines are 50 microns.

a. Section just anterior to fifth thoracic setal fascicle.

b. Section between sixth and seventh thoracic setal fascicles, showing association of ncphi idial

ducts with numerous blood vessels.

c. Section from abdominal region, showing size difference of ascending and descending

nephridial ducts.

d. Section close to transition between descending and ascending nephridial ducts, showing

similar size.

(\c. = ascending gut, AN = ascending nephridial duct, BV = blood vessel(s), BVS = blood vessels/

sinus associated with stomachic chamber, DG = descending gut, DN = descending nephridial duct,

LM = longitudinal muscle, NM = mesentery supporting nephridial ducts, sc = stomachic

chamber of descending gut, SF "> = fifth thoracic setal fascicle, sc: = sperm groove.)

54 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

PLATE 11

Caobangia abbotti, new species: Transverse sections, five microns, Mallory's Triple Stain

(USNM-W 50(i60); scale lines for a and c, 50 microns, for b and d, 10 microns.

a. Same section as Plate 5c, through posterior region beyond stomachic chamber and loops of

gut, showing relationship of "ovary," "testis," and larval ducts.

b. Section through "testis," showing spcrmatocytes and cluster of nearly mature sperm.

c. Section posterior to opening of duct from "testis" to sperm groove; actual opening is 10

microns anterior to this section.

d. Same section as c, more highly magnified.

(\r. = ascending gut, D<; = descending gut, i. = larva, u> = larval duct, o = "ovary," ov =

egg, oc;r = oocyte(s), so = stomachic chamber of descending gut, SOT = spermatocytc(s), SCL =

cluster of sperm, T = "testis," TD = tcsticular duct, YG = yolk granules.)

U.S. GOVERNMENT PRINTING OFFICE: 1974 S46-364/.2O
NUMBE

R 175

55

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