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CONTENTS

NAUTILUS

Volume 132, Number 2

June 29, 2018

ISSN 0028-1344

M.G. Harasewych

Lyubov Burlakova

Alexander Karatayev

Elsa Froufe

Arthur E. Bogan

Manuel Lopes-Lima

Richard L. Squires

Paul Lipman

Junlong Zhang

Peng Wei

Suping Zhang

Leonardo S. Souza

Carlos Henrique S. Caetano

The anatomy of Tudicla spirillus (Linnaeus, 1767) and the

relationships of the Tudiclidae (Gastropoda: Neogastropoda) ...............:..0004.

A new freshwater bivalve species of the genus Cyclonaias from Texas

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First occurrence of the Paleocene gastropod Ravniella

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A new species of Calliostoma (Gastropda: Calliostomatidae) from Weizhou

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Rediscovery of Cadulus podagrinus Henderson, 1920: redescription, new

records from the Bahamas, and discussions of its taxonomy (Scaphopoda:

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THE NAUTILUS 132(2):35—-44, 2018

Page 35

The anatomy of Tudicla spirillus (Linnaeus,

1767) and the

relationships of the Tudiclidae (Gastropoda: Neogastropoda)

M.G. Harasewych

Dept. of Invertebrate Zoology, MRC-163

National Museum of Natural History Smithsonian Institution

PO Box 37012

Washington, DC 20013-7012, USA

[email protected]

ABSTRACT

Descriptions are provided for the morphology of the shell,

operculum, radula, anatomy, egg capsules and juveniles of

Tudicla spirillus (Linnaeus, 1767), the type species of the type

genus of Tudiclidae. On the basis of these data, the family

Tudiclidae is transferred from the Turbinelloidea to the su-

perfamily Buccinoidea. Whether it maintains the rank of family

or becomes subordinated among the subfamilies of Buccinidae

will be determined by a thorough revision of the Buccinoidea

and its families. Such a revision will likely expand Tudiclidae to

include additional living genera, among them Afer, Euthria, and

Euthriostoma.

Additional Keywords: Turbinelloidea, Buccinoidea, neogastropod

phylogeny, anatomy, radula, radular morphology

INTRODUCTION

The family Tudiclidae, a widespread, diverse, and con-

spicuous component of tropical, shallow water, marine

communities during the Late Cretaceous and Paleogene,

has declined subsequently both in diversity and in geo-

graphical range. In the Recent fauna, it is believ wa to

be represented by a single species, Tudicla spirillus

(Linnaeus, 1767), restricted to the sublittoral sandy bot-

toms off southeastern India and Sri Lanka. As neither the

anatomy nor the radular morphology of this, the type

species of Tudicla were known, the composition and

systematic relationships of the Tudiclidae had been

inferred exclusively on the basis of shell morphology. Due

to its distinctive shell features, there has been general

agreement regarding the genera included in de. family

(e.g., Conse, 1901. Dzhalilov, 1977: Saul, 1988).

However, the taxonomic rank and phylogenetic rela-

tionships of the Tudiclidae have been subject to con-

flicting interpretations.

Cossman (1901: 60) proposed Tudiclinae [as Tudiculinae,

based upon an unjustified emendation of Tudicla Réding,

1798] as one of four subfamilies of Turbinellidae, together

with Turbinellinae, Fulgurinae, and Melongeninae. Because

of their conchological similarity, Thiele (1929: 342) listed

Tudicula H. and A. Adams, 1863, and Afer Conrad, 1858 as

sections of Tudicla, and included this genus in the family

Vasidae based on the radular morphology of Tudicula.

Thiele (1929: 320) also reduced Melongeninae and Ful-

gurinae to genera and transferred them to the family

Galeodidae |= Melongenidae]. Keene referring to Thie le’s

work, Finlay and Manwick (1937: 69) plevate d each of

Cossman’s turbinellid subeamilics s a family rank, noting that

“each marks and important group that has a separate history

over a very long period, and each comprises a rich variety of

form.” Wenz ai 943: 1303) followed Thiele (1929) in con-

sidering Tudicula to be among the subgenera of Tudicla,

but regarded Afer to be a separate genus within the fam-

ily mernme idee [as Vasidae]. Although some subsequent

workers, primarily paleontologists, reer family status to

this group (e.g., Zinsmeister, 1983: Saul, 1988: Stillwell and

Zinsmeister, 1992). Tudtdkdere had been regarded as

a subfamily of the Turbinellidae by most contemporary

workers (e.g, Rosenberg and Petit, 1987; Ponder and

Warén, 1988; Harasewych, 1998, Bouchet et al., 2005,

2017). However, there has been little consensus as to

the composition or taxonomic affinities of the Turbinellidae

(= Xancidae = Vasidae). This family has been referred to

the Buccinoidea (Sohl, 1964), the Volutoidea (e.g., Thiele,

1929; Wenz, 1943; Abbott, 1959; Taylor and Sohl, 1962) and

the Muricoidea, both in the narrow (e.g., Stoliczka, 1867;

Saul, 1988) and broad sense (e.g., Ponder, 1973; Boss, 1982;

Ponder and Warén, 1988; Vaught, 1989; Stillwell et al., 2004;

Bouchet et al., 2005), and most recently to the newly ele-

vated superfamily Turbinelloidea (F edosov et al., 2017:

Bouchet et al. 2017).

The similarity between the names Tudicla Roding,

1798 and Tudicula H. and A. Adams, 1863 has caused

numerous nomenclatural errors and confusion (reviewed

by Rosenberg and Petit, 1987: 58; Saul, 1988: 881), which

have obscured the evolutionary rel: ationships between

these conchologically similar but unrelated genera. The

establishment of Tudivasum Rosenberg and Petit, 1987,

as a replacement name for Tudicula sehonla eliminate

subsequent confusion with Tudicla.

Page 36

THE NAUTILUS, Vol. 132, No. 2

Although Tudicla spirillus, the type species of Tudicla,

is locally common, its distribution is limited to south-

eastern India and Sri Lanka at depths of 10-20 meters. It

has been reported to occur in the Lakshadweep Islands off

SW India (Bijukumar et al., 2015) and off Tamil Nadu,

India (Apte, 2004).

Through the kindness of Deepak Apte of the Bombay

Natural History Society and Dr. S. Antony Fernando of

Annamalai University, I was able to examine a series of

preserved specimens of Tudicla spirillus, its egg cases and

juveniles. This report presents descriptions of the gross

anatomy and spawn of Tudicla spirillus. The position of

Tudiclidae within Neogastropoda is revised on the basis of

these data.

MATERIALS AND METHODS

Specimens of Tudicla spirillus were trawled by fishermen

between Porto Novo and Puducherry India at depths

of 13-15 m, on a bottom of fine sand and mud. The shells

of several living animals were cracked, and the specimens

placed in 10% seawater formalin prior to shipment. Upon

arrival in Washington, the remaining portions of shell

were removed, and the fixed animals transferred to 70%

ethanol, in which they were stored until dissected.

Voucher material is de posite »d in the National Museum

of Natural History, Smithsonian Institution (USNM 894130).

Radulae of Afer afer (Gmelin, 1791)(USNM 894131)

collected in 15-25 m in Baie de Hann, Senegal, and Afer

cummingii (Reeve, 1844) (ANSP 307296) from off

Anping, Taiwan were obtained from dried specimens.

Shell fragments, larval shells, and radulae were

mounted on conductive tape, coated with carbon and

gold, and examined using a Hitachi S-570 Scanning

Electron Microscope.

SYSTEMATICS

Phylum Mollusca Linnaeus, 1758

Class Gastropoda Cuvier, 1797

Order Neogastropoda Wenz, 1938

Superfamily Buccinoidea Rafinesque, 1815

Family Tudiclidae Cossmann, 1901

Tudiculinae Cossmann, 1901: 60 [based on unjustified

emendation of Tudicla Réding to Tudicula (Cossmann,

1901:68)|

Tudiclidae Finlay and Marwick, 1937: 69.

Remarks: Tudiclidae has been well characterized by

Finlay and Marwick (1937), Zinsmeister (1983), Saul

(1988), and more recently by Stillwell and Zinsmeister

(1992). Diagnostic conchological features include a short

to anodteratte ly elevated spire, broadly shouldered whorls

that have tubercles or axial nodules on the angulations,

a long, axial siphonal canal, and a characteristic siphonal

fold that varies in distinctness among included genera.

Dzhalilov (1977) included the genera Tudicla, Pyropsis

Conrad, 1860, Pseudoperissolax Clark, 1918, Perissolax

Gabb, 1861, Napulus Stephenson, 1941, Medionapus

Stephenson, 1941, Perissitys Stewart, 1927, and Herco-

rhyncus Conrad, 1868 in the family, and provided a phy-

logenetic scheme of the relationships among these genera.

Zinsmeister (1988) also included Cophocara Stewart, 1927,

Heteroterma Gabb, 1869, and Nekewis Stewart, 1927, while

Saul (1988) added Tudiclana Finlay and Marwick, 1937, and

Rapopsis Saul, 1988, to the genera comprising Tudiclidae.

Genus Tudicla Roding, 1798

Tudicla Roding, 1798: 145 (Type species, Tudicla carinata

Roding, 1798 = Murex spirillus Linnaeus, 1767, by

subsequent designation of Angas, 1878: 611).

Pyrella Swainson, 1835: 21 (Type species, Turbinella

spirillus, by monotypy).

Spirillus F. Schliiter, 1838: 21 (Type species,

rostratus Schliiter, 1838 =

Pyrenella Gray, 1857:

monotypy).

Tudicula Ryckholt, 1862: pl. 33. Unjustified emendation

of Tudicla (see Rosenberg and Petit,1987: 59)

Tudicula Cossmann, 1901: 68, 70. Unjustified emendation

of Tudicla (see Rosenberg and Petit, 1987: 59)

Pyrula

Pyrula spirillus, by monotypy).

11 (Type species, Murex spirilla, by

Remarks: The rounded body whorl, distinctive induc-

tura, a long, well-demarcated siphonal canal, as well as

a sharply defined siphonal fold distinguish Tudicla from

related fossil genera.

Tudicla is reported to have ranged from eastern Africa

(Cox, 1925) to Poland (Abdel-Gawad, 1986) during the

uppermost Cretaceous. P: aleogene occurrences span Europe

and northem Africa, while Neogene records range from

Europe to India and Australia. Abbott (1959: 31) eral

the Recent species that had been referred to Tudicla by

previous authors and concluded that only T. spirillus belongs

to this genus. Rosenberg and Petit (1987:60) provide a list

of nominal fossil species referable to Tudicla.

Tudicla spirillus (Linnaeus, 1767)

Figures 1-25, Table 1

Murex spirillus Linnaeus, 1767: 1221, no. 554.

Tudicla carinata Roding 1798: 145.

Monoplex capitatus Perry, 1811: pl. 3, fig. 4.

Haustellum carinatum Schumacher, 1817: 213.

Spirillus rostratus Schliiter, 1838: 21.

Tudicla spirillus (Linnaeus)—H. and A. Adams, 1858:151.

Shell: Shell (Figures 1-4) medium-sized (to 85 mm),

solid, with mammillated protoconch, low spire (spire

angle 113°-122°), globose body whorl, and long,

narrow, axial, siphonal canal. Protoconch (Figures a

16, 17) axial, cylindrical, increasing in diameter from

0.6 to 2.5 mm in 1%4 smooth, chalky whorls. Transition

M.G. Harasewych, 2018 Page 37

Figures 1-11. Tudicla spirillus (Linnaues, 1767), USNM 894130, trawled between Porto Novo and Pondicherry, India, 13-15 m, fine

sand and mud. 1. Apertural, 2. Lateral, 3. Dorsal, and 4. Apical views of the shell. 5. Inner and outer surfaces of operculum. Scale bar =

3 cm for shell, 2 cm for operculum. 6. Protoconch. 7-8. Ultrastructure of adult shell. 7. Fracture surface. 8. Polished and etched surface.

Collabral orientation, approximately 1 cm behind outer lip. 9-11. Radula, in 9. Oblique, 10. Flat, and 11. Folded orientation.

Page 38

to teleoconch (Figures 16,17, arrows) demarcated by abrupt

appearance of strong shoulder, axial and spiral sculpture.

Teleoconch composed of up to 4% convex, broadly

shouldered whorls. Shoulder sharply keeled, with low, flat

nodes along its periphery. Suture adpressed along first

teleoconch whorl. flush with peripheral keel in subsequent

whorls. In larger specimens (4+ teleoconch whorls), the

suture may descend, abutting just below keel in last 4—4

whorl, returning to near the eal at the thickened outer lip

(Figure 2), possibly indicating determinate growth. Spiral

sculpture of closely spaced eo IG=N7 Bomeen suture and

shoulder, 21-28 between shoulder and siphonal canal, 7-13

along proximal 4 of siphonal canal. Axial sculpture limited to

weale flat nodes along the periphery (10-12 on body whorl)

and weak growth lines or striae. Aperture elliptical, major

axis deducted from shell axis of coiling by 32—35°. Outer lip

thickened, with spiral lirae pronounced near lip but dimin-

ishing interiorly within %4 whorl. As many as three sets of

spiral lirae, spaced 2 to %4 whorl apart, observed in sectioned

shells. Spiral lirae number 5-8 between suture and shoul-

der, 16-22 between shoulder and siphonal canal. The inner

lip is smooth, porcellaneous, with broad, flaring inductura

along anterior half. Posterior canal delimited by pronounced

callus at terminus of parietal ridge and most adaxial aper-

tural lira. Columella with strong siphonal fold that continues

onto inductura. Siphonal canal open, about 4 shell length,

and weakly sinuate. Narrow inductural callus extends to

siphonal fasciole situated near midpoint of siphonal canal.

Protoconch pinkish tan. Teleoconch pinkish tan, mottled

with reddish brown spots. Early whorls generally lightest in

color, distal half of the siphonal canal darkest. Aperture and

inductural callus white. Periostracum, where present, very

thin, composed of very fine minutely hirsute lamellae,

generally abraded away. Operculum (Figure 5) comeous,

broadly unguiculate, with terminal nucleus, attachment area

that spans most of inner surface, except for broad, glazed,

free band along abaxial edge. The operculum fills the

aperture within 1/6 whorl of the outer lip.

Ultrastructure:

two orthogonal layers of crossed-lamellar aragonite (Figures

7, 8). Outer layer, with crystal faces colabrally aligned, is

Shelleor (~ 1S ‘mm), comprises spiral and axial sculptural

elements. Inner layer, with crystal faces perpendicular to

growing edge, thickest (~ 1.0 mm) along the outer lip, and

comprises apertural lirae, callus and inductura. Larval shells

(ex-capsule) are composed a single layer (~ 50 jzm thick) of

collabrally oriented crystals (Figure 18).

External Anatomy: Retracted soft parts comprise 2%

whorls. Pallial cavity spans 4% whorl, kidney “4 whorl,

digestive gland 1% whorls. Foot nearly as broad as long,

operculum spanning entire foot width. Preserved animals

pinkish tan, weakly mottled with small, dark brown dots,

resembling shell in pattern and color. Siphon long and

simple, with broad, muscular fold that spans cea

at its inner proximal inner edge. Head small, with

short tentacles that barely extend beyond the small

eyes.

THE NAUTILUS, Vol. 132, No. 2

Outer lip of adult shells composed of

Pallial Cavity: Pallial cavity shallow, broad, with organs

disposed as in other neogastropods (Ponder, 1974: fig. 5).

Mantle edge slightly thickened, with small papillae along

its adapical half. “Osphradium is 2/3 as wide, 7/8 as long as

ctenidium. A narrow gap separates narrow hypobranchial

gland from ctenidium. Hypobranchial gland composed

of chevron-shaped pleats that line apex of the pallial cavity

and extend only slightly onto rectum and pallial gonoducts.

No purple pigment was detected in any of the specimens

examined.

Alimentary System: Rhynchostome (Figure 12, rh)

leads to long proboscis sheath (F igure 12, ps) that fills

entire cephalic hemocoel. Numerous short muscle fibers

attach it to dorsal and lateral walls of hemocoel, while

a long retractor muscle extend from its midpoint to the

rear of the hemocoel where it joins the columellar muscle.

Proboscis sheath muscular anteriorly, thin posteriorly,

containing convoluted, retracted proboscis (Figure 12,

pb) that approximates the shell in length when extended.

Buccal cavity nearly as large as the small (3 mm) buccal

mass. Radular sac Tong (~ 11 mm), containing triserial

radula of 116-122 (n = 5) rows of teeth, each row

composed of a tricuspid rachidian tooth flanked on each

side by a tricuspid lateral tooth (Figures 9-11). Rachidian

teeth very slightly broader than lateral teeth, with 3 cusps

emerging Prot the central third of a broadly attached

basal plate. Outermost cusp of lateral teeth twice as long,

thicker than central and inner cusps. The anterior

esophagus (Figure 12, ae), which contains the ducts of the

salivary glands embedded beneath the dorsal folds, runs

through “Ghee proboscis, from the posterior end of the

proboscis sheath along its ventral surface to the nerve

ring at the anterior margin of the cephalic hemocoel.

Salivary glands (Figure 12 sg) lie beneath the proboscis

sheath near the nerve ring. Accessory salivary glands are

absent. A slight swelling of the esophagus just anterior to

the nerve ring marks the valve of Leiblein (Figure 12, vl).

After passing through the nerve ring the mid-esophagus

is joined by a narrow duct from adie gland of Leiblein

(Figure 12, gl). This gland is short, Seidl brownish,

toneltecent tapers posteriorly, and does not reach the

rear of the hemocoel. The posterior esophagus runs

along the floor of the hemocoel together with the

anterior aorta and paired odontophore — retractor

muscles, and joins the stomach (Figure 12, sto) along

the anterior face of the digestive gland. The tubular

stomach forms a nearly complete circle along the

anterior and dorsal surfaces of the digestive gland. A

distinct caecum is present in the stomach and the ducts

of the digestive gland are widely separated, lying at

opposite ens of a gastric lumen bounded by large,

irregular typhlosoles. The intestine (Figure 12, 70) is

narrow, broadens upon entering the mantle cavity to

form the rectum (Figure 12, r), then again constricts,

running alongside the pallial gonoduct and terminating

roughly 1 cm from the mantle edge. The anus (Figure 19%

a) is detached from the pallial wall and lacks a papilla. An

anal gland is not present.

M.G. Harasewych, 2018

Page 39

Figures 12-14.

sto

Anatomical features of Tudicla spirillus. 12. Alimentary system. 13. Male reproductive system. 14. Female reproductive

rpc SV

system. Abbreviations: a, anus; ae, anterior esophagus; bu, bursa copulatrix; eg, capsule gland; gl, gland of Leiblein; int, intestine; nr, nerve

ring; od, oviduct; ov, ovary; p, penis; pap, papilla; pb, proboscis; pr, prostate; ps, proboscis sheath; r, rectum; rh, rhynchostome; rpe, rear of

pallial cavity; sg, salivary gland: sto, stomach: sv, seminal vesicle: td, testicular duct: te, testis: vl, valve of Leiblein.

er Reproductive System: The testis (Figure 13,

te), lines the adapical and adaxial sides of the digestive

gland. A testicular duct (Figure 13, td) runs anteriorly,

forming a convoluted seminal vesicle (Figure 13, sv) that

extends from the posterior portion of the stomach, along

the kidney , across the posteniormost region of the peri-

cardium, to the rear of the pallial cavity (Figure 13, rpe),

where it expands to become thick, glandular, and sur-

rounded by a thick muscle layer. The prostatic portion of

the duct (Figure 13, pr) runs along the pallial wall, de-

scends to the floor of the mantle cavity at mid-length and

leads to the base of the penis (Figure Ta, p). The penis is

short (spanning < 4 the mantle c ‘avity when retracted),

dorsoventrally compressed, broadest near the distal end,

and has a broadly conical papilla (Figure 13, pap). The

duct is situated within the central portion of the penis.

Female Reproductive System: The ovary (Figure 14,

ov) lines the adaxial side of the digestive gland and is

composed of a series of acinous tubules that converge

on the oviduct (Figure 14, od). This narrow, trans-

luscent duct leads anteriorly, joining the pallial gon-

oduct at the right anterior wall of the kidney. The

pallial gonoduct is composed of a long (~ 25 mm),

tubular (~ 9 mm diameter) capsule gland (Figure 14,

cg) and a bursa copulatrix (Figure 14, be). No mor-

phologically distinct ingesting gland or albumen gland

were discerned. The capsule gland has thick, glandular walls

and a sigmoidal dorso-ventral lumen. The posterior 4 of the

gland differs in color and consistency, its lumen is continuous

saith that of the anterior portion of the gland but rotated

about 30° counter-clockwise. At the anterior margin of the

capsule gland, two darkly pigmented bands of tissue flank

the fencn at the entrance of the duct from the bursa

copulatrix. The bursa copulatrix (Figure 14, bu) consists

of a coiled glandular tube enclosed in a mass of connective

tissue. An adjacent anterior flap protects its opening

(Figure 14, fo).

Page 40 THE NAUTILUS, Vol. 132, No. 2

Figures 15-21. Tudicla spirillus (Linnaeus, 1767). 15. Apertural, 16. Dorsal, and 17. Apical views of pre-emergent hatchlings. Arrow

indicates transition between protoconch and teleoconch. 18. Fracture surface of hatchling shell, collabral orientation, approximatly

| mm behind outer lip. 19. Radula of hatchling. 20. Radula of Afer afer (Gmelin, 1791), USNM 894131, from 15-25 m, off Baie de

Hann, Senegal. 21. Radula of Afer cummingii (Reeve, 1844), ANSP 307296, from off Anping, Taiwan.

Spawn: The spawn mass of Tudicla spirillus (Figures a columnar, double helical arrangement of 40—56 (n = 8)

22-23) was briefly discussed and illustrated by Pinn capsules forming a left-handed spiral. Individual strands

(1992), who attributed it to this species by deduction. are anchored to hard substrates (shells, rocks) or branch

It is described in more detail here. It consists of from conspecific egg strands. Capsules are deposited as

M.G. Harasewych, 2018

Page 41

94}

Figures 22-25. Tudicla spirillus (Linnaeus, 1767). 22. Lateral and 23. Dorsal views of complete egg strand attached to a cardiid

valve. 24. Ventral and 25. Dorsal views of individual egg capsule. Abbreviation: ha, preformed hatching aperture.

roughly opposing pairs, and attached along their bases

at angles of 48—106° (counterclockwise) from the preceding

pair, forming and offset, pentagonal arrangement (Figure 23).

Individual capsules (Figures 24, 25) are roughly discoidal,

strongly asymmetrical, with a broad attachment area and

a wide, outwardly directed, pre-formed hatching aperture

sealed with a mucoprotein plug. The number of ova initially

deposited in each capsule is unknown. Ten capsules from

each of eight strands were examined and each invariably

contained two juveniles (Figures 15-17) ready to hatch.

Kidney: The large kidney (spanning 4 whorl) is situated

to the right of an elongated pericardium. The nephridial

gland, which borders the entire length of the pericardium

along the dorsal left surface of the kidney, is 3-4 times

broader anteriorly than posteriorly. Viewed from within

the kidney, this organ is composed of vertical fibrous

bundles, separated by narrow, slit-like invaginations. The

kidney is of the pycnonéphridiens type (Perrier, 1889)

with the primary and secondary lamellae interdigitated along

the dorsal and lateral walls of the kidney. The primary

lamellae, emanating from the ventral branch of the

afferent renal vein, number 7-8, and are heavily pleated.

The secondary lamellae, emanate from the dorsal branch of

the afferent renal vein, are weak in the anterior portion of

the kidney, becoming more conspicuous posteriorly.

>. > ¢

Page 42

THE NAUTILUS, Vol. 132, No. 2

Tudicla spirillus. Measurements of shell characters. Linear measurements in mm. (n = 10). Juveniles (n =10) all from

Table 1.

a single strand of capsules.

Character Mean

ADULTS

Shell length (SL) 68.6

Shell width (SW) 39.4

Aperture length (AL) XII

Siphonal canal length (SCL) 35.5

AL/SL 0.323

SCL/SL 0.517

Spire Angle LINZ

Whorls, protoconch LoS

Whorls, teleoconch 3.96

Nodes along shoulder 11.4

Spiral cords

Suture — shoulder 14.]

Shoulder — siphonal canal 24.6

Siphonal canal 9]

JUVENILES AT HATCHING

Shell length 7.1

Whorls, protoconch 1.8

Whorls, teleoconch 0.5

Nervous System: The nervous system is of the typical

stenoglossan type, with all circum-esophageal ganglia

highly concentrated. The supra-esophageal ganglion. is

closely attached to the right pleural ganglion.

DISCUSSION

The attribution of extinct genera to Tudiclidae by pale-

ontologists has been base d on distinctive shell features

shar ae with the type species Tudicla spirillus, presumed

to be the only living species within the family. Abbott

(1959) recognized the relationship of living species of the

genus Tudicula (now Tudivasum, see Rosenberg and

Pe tit, 1987) to Vasum based on morphology of both

shell and radula, but did not consider Tudicla to be closely

related to either of these genera. As the anatomy and

radular morphology of Tudie la had not been studied, the

inclusion of Tudiclidae within Turbinelloidea has been

tentative, based on similarities of its shell to those of some

species of Tudivasum.

The anatomy of Tudicla spirillus conforms to the basic

neogastropod ¢ ground plan (Ponder, 1974). Several fea-

tures, among ‘them the absence of accessory salivary

glands, and a kidney of the pycnonéphridiens type are

consistent with those characterizing the superfamily

Buccinoidea and at least some ANSE of the Turbi-

nelloidea (Ponder, 1974: Table 2). Other features, such

as the lack of columellar folds in the shell and the ab-

sence of an anal gland, are shared with Buccinoidea, but

not with Tanda lloidea. Although Ponder (1974: Ta-

ble 2) reported that an anal gland was present in Tur-

binellinae but absent in Vasinae, Medinskaya et al. (1996:

60) reported that it was present but very small in Vasum

muricatum. The occurrence of a long proboscis folded

within a proboscis sheath is prevalent in Scrarhmellordlen but

SD Range

6.6 57.9-75.9

B7/ 33.0-45.1

2.1 19.5-25.7

3.9 28.9-40.8

0.016 0.290-0.342

0.016 0.498—0.617

4.28° 113.8°—121.5°

0.12 1.5-2.0

0.26 3.7-4.5

0.8 10-12

1.1 IG=1'7/

DI 21-28

7/ THN8

0.5 6.5-8.3

0.3 IL 5—9.7/

0.1 ().3-0.8

also occurs in some buccinoideans (e.g., Melongenidae,

Colubrariidae), while a sperm duct that is closed throughout

the pallial cavity and passes through the central portion

of the penis in Tudicla spirillus, differs from the open

pallial sperm groove and penial groove that occur in

Turbinelloidea.

The morphology of the egg mass of Tudicla spirillus,

with the first several capsules s attached to a hard sub-

strate and subsequent capsules added with preformed

hatching apertures directed outwardly in a columnar

array, re agains those of the buccinid genus Nepiunea

Roding, 1798 (e.g., see Golikov, 1963: “figs. 70, 72; pl.

26, fig la). Egg capsules of iPneitaclie pyrum and

Turbinella ongpellatie resemble those of Busyconinae,

comprising a aver: strand in which each of 10-28 coin-

shaped capsules is attached at its base, parallel to the

previously deposited capsule. Earliest capsules are

buried in the sand to form an anchor, subsequent

capsules are free forming a strand (Hornell, 1951:24,

fig. 20; Bandel, 1976: figs. 17a—c, 19). Spawn of Vasum

muricatum contain from 3 (D’Asaro, 1970: figs. 7a—b)

to 13 capsules (Bandel, 1976: figs. 16a—b, 19), Each

capsule was broad and low, individually attached to

the substratum, with the hatching aperture situated

apically.

The morphology of the radula of Tudicla spirillus,

particularly the presence of tricuspid rachidian teeth and

tricuspid lateral teeth with the outer cusp longest, most

clearly precludes the inclusion of Tudiclidae in Turbi-

nelloidea and indicates a relationship within the Bucci-

noidea. Fraussen and Haddorn (2000) transferred the

genus Afer from the Turbinellidae to Buccinidae based

upon examination of the radulae of several species, which

they reported as being typically buccinid, noting simi-

larities to the radular teeth of Buccinulum vittatum (Quoy

M.G. Harasewych, 2018

D} > £

Page 43

and Gaimard, 1833) and Euthria cornea (Linnaeus, 1758).

The radula of Afer afer (Gmelin, 1791) (Figure 20) the

type species of Afer, and Afer cummingii (Reeve, 1844)

(Figure 21) are extremely similar to Those of Tudicla

spirillus, suggesting a close relationship.

Based on hess fobconations the family Tudiclidae is

transferred from the Turbinelloidea to the superfamily

Buccinoidea. Whether it retains the rank of family, or

becomes subordinated among the subfamilies of Buccini-

dae will require a thorough revision of the Buccinoidea and

its constituent families aul subfamilies. Such a revision will

likely expand Tudiclidae to include additional living genera,

among them Afer, Euthria and Euthriostoma.

ACKNOWLEDGMENTS

I am most grateful to Deepak Apte and Dr. S. Anthony

Fernando for obtaining and preserving the specimens

used in this study. This paper would not have been

possible without their assistance. Thanks are due to

Robert Foster, of Abbey Shells, for kindly providing

a specimen Afer afer that contained a dried animal.

Scanning Electron micrographs were taken by Susanne

Braden oe the National Museum of Natural History’s

Scanning Electron Microscopy Laboratory. Illustrations

of egg capsules were produced by Molly Kelly Ryan.

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THE NAUTILUS 132(2):45-50, 2018

Page 45

A new freshwater bivalve species of the genus Cyclonaias from

Texas (Unionidae: Ambleminae: Quadrulini)

Lyubov Burlakova

Great Lakes Center

SUNY Buffalo State College

1300 Elmwood Avenue

Buffalo, NY 14222, USA

Alexander Karatayev

Great Lakes Center

1300 Elmwood Avenue

Buffalo, NY 14222, USA

Arthur E. Bogan'

North Carolina State Museum of

Natural Sciences

Research Laboratory, MSC 1626

Raleigh, NC 27699-1626, USA

Research

SUNY Buffalo State College

Manuel Lopes-Lima?™

CIIMAR/CIMAR-Interdisciplinary

Centre of Marine and Environmental

University of Porto, Terminal

Elsa Froufe

CHMAR/CIMAR-Interdisciplinary

Centre of Marine and Environmental

Research

University of Porto, Terminal

de Cruzeiros do Porto de Leixées

Avenida General Norton de Matos, S/N

4450-208 Matosinhos, PORTUGAL

de Cruzeiros do Porto de Leixdes

Avenida General Norton de

Matos, S/N

4450-208 Matosinhos, PORTUGAL

and

CIBIO/InBIO-—Research Center in

Biodiversity and Genetic Resources,

University of Porto, Campus Agrario

de Vairao, Vairao, PORTUGAL

ABSTRACT

Cyclonaias necki, a new species from the San Marcos River in

the San Antonio/Guadalupe River Basin in Gonzalez County,

Texas, USA, is here described and separated from Cyc lonaias

petrina based on shell morphology and molecular barcoding

analyses.

Additional Keywords: Freshwater Bivalve, San Marcos River,

Guadalupe County, Caldwell County

INTRODUCTION

On the last revision of the freshwater mussels of the

United States of America and Canada, 14 Cyclonaias

species were recognized (Williams et al., 2017), six of

which occur in Mee (Howells, 2013). One of these

species is the Texas Pimpleback Cyclonaias petrina

' Author for correspondence

* SSC/IUCN—Molluse Specialist. Group, Species Survival

Commission, International Union for Conservation of Nature, c/o

The David Attenborough Building, Pembroke Street, Cambridge

CB2 3QZ, UNITED KINGDOM

(Gould, 1855) distributed across the Colorado and San

Antonio/Guadalupe River systems. However, specimens

recently collected for this study in the San Marcos River in

the San Antonio/Guadalupe River Basin, revealed clear

conchological and genetic differences from those in the

Colorado basin, raising the question of the existence of

two distinct species in south central Texas. This paper

presents the description of Cyclonaias necki new spe-

cies. A subset of the authors of the current paper,

Burlakova, Karatayev, Lopes-Lima, and Bogan, are

the authors of the new species.

MATERIALS AND METHODS

Eleven specimens, all previously identified as Cyclonaias

petrina, were collected from the Concho River (Colorado

River Basin) [4 specimens], San Saba River (Colorado

River Basin) [3 specimens] and San Marcos River (San

Antonio/Guadalupe River Basin) [5 spe cimens] (Table 1)

in 2008-2011, as part of the project “State-wide Assess-

ment of Unionid Diversity in Texas” (Federal Aid Grant

No. T-43 funded by the US Fish and Wildlife Service

State Wildlife Grant Program through the Texas Parks and

Wildlife Department (TPWD), 2008-2012). The work

was carried out with an appropriate Scientific Research

Page 46

THE NAUTILUS, Vol. 132, No. 2

Table 1.

List of all individual specimens used for genetic analyses, catalog numbers, collection sites, and GenBank references. BSGLC

(SUNY Buffalo State College Great Lakes Center); NCSM (North Carolina Museum of Natural Sciences); UF (Florida Museum of

Natural History).

Species

Cyclonaias petrina

Cyclonaias necki

Locality

Paint Rock

San Saba

Palmetto State Park

Catalog number

BSGLC 1617

BSGLC 1619

BSGLC 1620

BSGLC 3254

BSGLC 3255

BSGLC 2157

BSGLC 1672

Cyclonaias necki Luling NCSM 65378

Cyclonaias necki Luling BSGLC 2255

Cyclonaias necki Luling BSGLC 2256

Cyclonaias necki Luling UF 441084

Permit SPR-0503-300 issued by the TPWD. Specimens

were placed in 99% ethanol for molecular analyses. The

holotype and a paratype were deposited in the North

Carolina Museum of Natural Sciences (NCSM), and the

remaining paratypes and other specimens in the Great Lakes

Center Invertebrate Collection (BSGLC) (SUNY Buffalo

State College, Buffalo, NY) (Tables 1, 2).

Sequencing, PCR Amplification, and Dataset

Construction: For each sample, amplification and

(bidirectional) sequencing was carried out for cytochrome

c oxidase subunit I (COI) with the primers LCO_22me

and HCO_700dy (Walker et al., 2006) with annealing

temperature of 50°C and the remaining polymerase

chain reaction (PCR) conditions as described in Froufe

et al. (2014). Sequences were obtained with the BigDye

sequencing protocol (Applied Biosystems 3730x1l) by

Macrogen Inc., Korea. Forward and reverse sequences

were edited and assembled using ChromasPro 1.7.4

(Technelysium, Tewantin, Australia). All new sequences

have been deposited in GenBank (Table 1). A COI dataset

was then constructed with the newly sequenced indi-

viduals and one Quadrula petrina present in GenBank

(Table 1) [San Marcos River, southwest of Luling,

Caldwell/Guadlupe County Line, Texas (Pfeiffer et al.,

2016)]. The dataset was aligned using the MAFFT multiple

sequence alignment algorithm (Katoh and Standley, 2013)

with default parameters.

Table 2.

River (Basin) GenBank

Concho River (Colorado) MG969416

Concho River (Colorado) MG969417

Concho River (Colorado) MG969418

San Saba River (Colorado) MG969419

San Saba River (Colorado) MG969420

San Saba River (Colorado) MG969421

San Marcos River (San Antonio/Guadalupe) MG969422

San Marcos River (San Antonio/Guadalupe) MG969423

San Marcos River (San Antonio/Guadalupe) MG969424

San Marcos River (San Antonio/Guadalupe ) MG969425

San Marcos River (San Antonio/Guadalupe ) KT285656

Molecular-based Species Delineation Methods: Two

distinct molecular methods were applied to determine

the number of Molecular Operational Taxonomic Units

(MOTUs). The first is distance based, ie. the BIN system

implemented in BOLD (Ratnasingham and Hebert, 2013)

widely used as the standard COI barcoding method. For the

BINs system, the COI dataset was analyzed with the Cluster

Sequences tool implemented in BOLD 4 (http://v4.

boldsystems.org) (Ratnasingham and Hebert, 2013). The

second species delineation method used the 95% statistical

parsimony connection limit in TCS 1.21 (Clement et al., 2000).

SYSTEMATICS

Class Bivalvia Linnaeus, 1758

Order Unionida Gray, 1854

Family Unionidae Rafinesque, 1820

Genus Cyclonaias Pilsbry in Ortmann and Walker, 1922

Cyclonaias necki Burlakova, Karatayev, Lopes-Lima,

and Bogan new species

Common Name: Guadalupe Orb

(Figures 1—4)

Comparative Diagnosis: Younger shells of Cyclonaias

necki new species are diagnosed by the distinct corrugations

Measurements of Cyclonaias necki new species type specimens.

Type Catalog number Shell length mm Shell height mm Status

Holotype NCSM 65378 42 30 Live

Paratype NCSM 65379 60 42 Live

Paratype BSGLC 225] 63 42 Live

Paratype BSGLC 2252 58 38 Live

Paratype BSGLC 2253 54 37 Live

Paratype BSGLC 2255 43 30 Live

Paratype BSGLC 2256 45 32 Live

Paratype BSGLC 2257 40 29 Live

Paratype BSGLC 2258 47 33 Fresh dead

Paratype BSGLC 2259 40 28 Fresh dead

Paratype BSGLC 2260 36 27 Fresh dead

L. Burlakova et al., 2018

Page 47

Figures 1-4. Cyclonaias necki new species. 1-2. Holotype NCSM 65378, shell length 42 mm. 1. Outside of right valve. 2. Inside of

left valve. 3-4. Paratype BSGLC 2255, shell length 43 mm. 3. Outside of right aA 4. Inside of left valve.

across the posterior slope, extending onto the disk of the

shell from the posterior ridge, and lack of pustules

(Figures 1-4). Cyclonaias petrina (Figures 5-8) has

weaker or missing corrugations, typically lack the corru-

gations on the disk of the shell, and may have occasional

pustules. Cyclonaias petrina has a thick, inflated shell with

a rounded shell disk and round shell shape with an in-

distinct posterior ridge. Shells of Cyclonaias necki new

species are thinner, more compressed and rectangular,

and the posterior ridge is more distinct and prominent.

The umbo on shells of C. petrina appears broader and

more inflated, while in C. necki new species, it is more

compressed. Pseudocardinal teeth in C. petrina are larger

and thicker than in C. necki new species. The interdentum

of both species are about the same size in relation to shell

length. Lateral teeth are short in both species. The umbo

cavity of C. petrina is deep and open, but appears slightly

more compressed in C. necki new species. Both species

are closely related to Cyclonaias nodulata (Rafinesque,

1820), which is very inflated, thick shelled, and usually

characterized by two rows of pustules down the disk of the

shell, but lacking a sulcus between the rows as seen in

Quadrula quadrula (Rafinesque, 1820).

Description: Shell Jength reaches about 63 mm, shell

height about 42 mm. Shell shape subquadrate to suboval,

shell moderately inflated and relatively thin. Anterior shell

margin broadly rounded, dorsal shell margin straight to

slightly convex, ventral shell margin slightly convex,

posterior shell margin obliquely truncate. Posterior ridge

rather well-defined becoming rounded with age. Some

specimens have a secondary ridge between posterior ridge

and posterior shell margin. Posterior slope covered wath

fine corrugations running from posterior ridge to posterior

shell margin. Umbo area full and well developed, rising

above hinge line. Umbo sculpture begins as a series a

bars, becomes bumps at either end of a bar, diverging to

small bumps down umbo. Periostracum y llowidh « green to

green becoming brown with age, often with fine green

rays becoming obscured with age. Shell surface smooth

with no pustules, some younger specimens with corruga-

tions extending from posterior ridge anterior ventrally,

Page 48

THE NAUTILUS, Vol. 132, No. 2

Figures 5-8. Cyclonaias petrina. 5-6. BSGLC 1620, shell length 88 mm, Concho River, Concho County, Texas 31.51982N,

099.94063W. 5. Outside of right valve. 6. Inside of left valve. 7-8. BSGLC 2250, San Saba River, San Saba County, Texas, 31.21064N,

098.74124W; shell length 26 mm. 7. Outside of right valve. 8. Inside of left valve.

disappearing by central area of shell disk. Sculpture becoming

obscured or eroded in older specimens. Single large pseudo-

cardinal tooth in right valve with a vestigial ‘tooth anterior to

main tooth, two large sculptured teeth in left valve. Inter-

dentum is well developed in both valves. Lateral tooth single

and straight in right valve with two well defined teeth in left

valve. Anterior adductor muscle scar deep and smooth, pedal

protractor muscle scar deep, separate from, and located

posterior and slightly ventral to anterior adductor muscle

scar. Anterior pedal retractor muscle scars are deep pits at

base of pseudocardinal teeth and almost merge with anterior

adductor muscle scar. Posterior adductor muscle scar well

defined, but shallow, posterior pedal retractor muscle scar

dorsal to posterior adductor muscle scar and merges with

posterior adductor muscle scar. Pallial line well defined

anteriorly and becoming fainter posteriorly. Umbo cavity

deep and open. Nacre color white and iridescent posteriorly.

Type Material: Holowpes NCSM 65378 [ex BSGLC

2254]: Paratypes: BSGLC 2251, 2252, 2253, 2255, 2256,

2259, 2260; NCSM 65379 [each lot is a single ae

(Table 2). All from type locality, collected by Lyubov E

Burlakova, Alexander Y. Karatayev, Vadim A. Karatayev,

on July y 12, 2011.

Type Locality: San Marcos River, between US90 and

SRS0, southwest of Luling, Caldwell/Guadalupe counties

(the river is the border), Latitude 29.67078 N, Longitude

097.69561 W.

Comparison with Similar Species: Cyclonaias necki

new species was reported by Strecker (1931) as a small

variety, but not separate from C. petrina. Cyclonaias necki

new species was noted by Howells (2013) as “the eco-

phenotypes in the Guadalupe-San Antonio drainage are

often somewhat more elongate, thinner shelled, and with

less robust hinge teeth.” Cyclonaias aurea (Lea, 1859) re-

sembles C. necki new species but lacks the corrugations on

the posterior slope and the disk of the shell. Cyclonaias

nodulata (Rafinesque, 1820) is more inflated, thicker

L. Burlakova et al., 2018

ayaa AIC

Page 49

shelled than C. necki and is marked by two variable rows of

pustules or knobs down the disk of the shell, but lacking

a sulcus found in Quadrula quadrula and Q. apiculata (Say,

1829) and the numerous pustules of these two species.

Cyclonaias necki new species resembles some Fusconaia

species, but these species lack the corrugations on the

posterior slope.

Molecular Analyses: The COI alignment was 596 base

pairs (bp) long and included 7 haplotypes, 4 from the San

Antonio/Guadalupe River drainage and 3 from the

Colorado River Basin. Two MOTUs were identified

by both species delineation methods: one corresponding

to the specimens of Cyclonaias petrina from the Colo-

rado basin and another corresponding to the specimens

of Cyclonaias necki new species from the San Marcos

River. The interspecific COI divergence (3.9%, uncorrected

p-distance) is within the usual range for the Unionidae

(Prié and Puillandre, 2014; Lopes-Lima et al., 2017).

The intraspecific COI divergence within each MOTU

was <1%.

Distribution: Cyc lonaias petrina was recognized from

the Colorado River Basin and “A small variety is found in

the Guadalupe River in Comal County” was ‘reported by

Strecker (1931). It was subsequently ‘reported from the

Guadalupe and Colorado River basins and from the Llano,

San Saba, and Pedernales rivers (Howells et al., 1996), and

recently from the Concho, Guadalupe, San Gala, and San

Marcos rivers (Burlakova et al., 2011; Burlakova and

Karatayev, unpublished data). The range was listed as

“endemic to the Colorado and Guadalupe-San Antonio

systems of Central Texas” (Howells, 2013). Cyclonaias

petrina was recognized by Williams et al. (2017). Here, we

have separated C. necki new species from C. petrina and

recognize C. petrina as restricted to the Colorado River

Basin with C. necki new species endemic to the

Guadalupe-San Antonio River Basin of Central Texas.

Habitat and Biology:

gravidity are unknown. Cyclonaias necki new species was

found living in a small river in flowing water with a sand

and gravel substrate, mostly in water less than 2 m.

Conservation Status: Cyclonaias petrina was con-

sidered threatened (Williams et al., 1993). This new

species has been split from Cyclonaias petrina which is

listed by Texas Parks and Wildlife Department as legally

threatened (Howells, 2013). The US Fish and Wildlife

Service (USFWS) has been petitioned to examine C.

petrina for federal listing as threatened or endangered

(USFWS, 2018). Their evaluation reported C. petrina

as having occurred historically in 38 counties, but was

listed only from 16 counties ‘today. By recognizing C.

necki new species from the San Antonio/Guadalupe

River Basin, this restricts the modern distribution of

C. petrina to eight counties in the Colorado River

Basin and the range of C. necki new species to eight

counties. This defines the modern range of C. petrina to

half of the USFWS listed counties (USFWS, 2018).

Host fish and the period of

Considering the restricted range, we would suggest C.

necki new species and C. petrina warrant listing as

endangered.

Etymology: We take this opportunity to name the new

species, recognizing his work on freshwater mussels of

Texas, after Raymond W. Neck, a pleasant and helpful

friend (1946-2017).

Comparative Material Examined: Shells of Cyclo-

naias petrina examined for comparison included BSGLC

1620, 2128, 2133, 2156, and NCSM 33710 and 33713.

ACKNOWLEDGMENTS

Mrs. Cynthia M. Bogan and Ms. Jamie M. Smith have

reviewed this manuscript and provided helpful com-

ments. Ms. Smith is thanked for removing the back-

ground of the eight figures used here.

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THE NAUTILUS 132(2):51-57, 2018

Page 5]

First occurrence of the Paleocene gastropod Ravniella Rosenkrantz,

1970 (Heterobranchia: Acteonidae) in North America

Richard L. Squires

Department of Geological Sciences

California State University

Northridge, CA 91330-8266, USA

Paul Lipman

Wesierski & Zurek, LLP

100 Corson St.,

Pasadena, CA 91103 USA

Suite 300

and [email protected]

Invertebrate Pale ontology’

Natural History Museum of Los Angeles County

Los Angeles, CA 90007, USA

richard squire [email protected]

ABSTRACT

A new species of the acteonid heterobranch gastropod, Ravniella

lipmanorum Squires, is described from upper lower Paleocene

(upper Danian) strata in southern California. This is first record

of genus Ravniella Rosenkrantz, 1970 in North America. This

small-sized genus, which has a broad callus pad bearing two

columellar plaits and one parietal plait, is known elsewhere only in

Paleocene strata in Denmark, Poland, Austria, and western

Greenland. The new species is found mainly at a single locality in

the lower part of the Santa Susana Formation, ory: side of Simi

Valley, Ventura County. At this locality, specimens are associated

with abundant shallow-marine mollusks, which underwent rela-

tively short-distance, post-mortem transport, probably by turbidity

currents emanating from shallower marine depths. The new

species is found rarely in the lower part of the San Francisquito

Fornation, Warm Springs Mountain area, Los Angeles County.

Ravniella occurs questionably in Upper Cretaceous strata of

northern Spain (Campanian). The senior author, Squires, is the

sole author of the new species.

Additional Keywords: Tomatellaea, Ringicula, paleobiogeography

INTRODUCTION

Since at least the Late Triassic, shell-bearing “lower

heterobranch” gastropods, which were traditionally re-

ferred to as shelled “opisthobranchs,” have been an im-

portant component of shallow-marine gastropod faunas

(Griindel and Niitzel, 2012). Today “lower hetero-

branchs” represent one of the most diverse lineages in

Mollusca, but evolutionary relationships remain in-

complete (Kano et al., 2016). One of the earliest “lower

heterobranch” groups is family Acteonidae d’Orbigny,

1842, which first appeared during the Middle Jurassic in

Europe (Griindel et al., 2012). Modern-day acteonids prey

1 .

Research Associate

mainly on polychaete worms, to such an extent that, according

to Helwerda (2015), the presence of acteonids in an area

indicates that polychaete worms must also be present. Yonow

(1989) reported on a modern-day acteonid, which is a spe-

cialized vermivore, feeding only on tube-dwelling polychaete

worms. This acteonid eens along the surface ae patches of

clean, well-sorted, medium to ae sand, and, upon detecting

its prey, burrows 5 to 10 cm to reach the worm tube.

This present paper concerns the recent discovery of a

new species of the acteonid genus Ravniella Rosenkrantz

(1970) from lower Paleocene rocks at two localities in

southern California. Ravniella has been traditionally

a subgenus of Tornatellaea Conrad, 1860, but some

workers (e.g., Kollmann and Peel, 1983; Schnetler, 2001;

Blagovetshenskiy, 2017) used Ravniella as a distinct ge-

nus. None, however, described, in detail, how Ravniella

differs from Tornatellaea. These differences are given

here. The discovery of the new species, Ravinella lip-

manorum Squires, is significant because this genus had

been found before only in Paleocene rocks in western

Europe and western Greenland.

Most specimens of the new species are from the lower Santa

Susana Formation in northern Simi Valley, Ventura County,

southem Califormia, but two are from the lower San Fran-

cisquito Formation, Warm Springs Mountain area, Los Angeles

County, southern California (Figure 1). The new species most

likely inhabited nearshore-marine depths but underwent post-

mortem transport into dee sper waters. The senior author,

Squires, is the sole author of this new species.

MATERIALS AND METHODS

The new species is based on 44 specimens stored in the

Invertebrate Paleontology Collection of the Natural

History Museum of Los Angeles C ounty (LACMIP).

Details about the localities of the new species are given in

Appendix 1. Most of the specimens were found in Simi

Valley at LACMIP locality 41691, discovered by the junior

Diavarm (6

Page 52

THE NAUTILUS, Vol. 132, No. 2

Localities

1 - LACMIP 41691, north

side Simi Valley

2 - LACMIP 21581, near

Warm Springs Mtn.

Figure |

author in 2015, when he was prospecting for fossils in an

area undergoing construction of a road, to provide access

to a planned development of nearby homesites. A search

of the LACMIP Collection yielded two additional spec-

imens of the new species. They were found by an early

collector, in the 1940s, in the Warm Springs Mountain

area (see Appendix 1).

Cleaning of apertures was done by careful use of very

sharp nee ile 5. The classification system of Bouchet et al.

(2017) is followed here, but “categories” higher than super-

family remain mostly in a state of fibre Ge eral morphologic

terms are from Cox (1960), and protoconch terminology is

from Schroder (1995).

STRATIGRAPHY, DEPOSITIONAL

ENVIRONMENTS, AND AGES

Nearly all the specimens are from LACMIP loc. 41691, in

the lower part of the Santa Susana Formation, on the north

side of Simi Valley, southern California. As recognize od by

Parker (1981: fig. 4 4), this formation consists of an “eastern

facies” (mostly slope and inner-fan turbidite deposits) and

a “western facies” (nearshore to offshore deposits). Fossils

at locality 41691 occur in the “eastern facies,” which typ-

ically contains sparse macrofossils. Fossils at this locality

are, however, unusually abundant. They are in float derived

from a nearly completely covered, approximately 25 cm-

thick Turritella-rich storm bed which caps a low hill

consisting of 30 m of of black silty mudstone, which

weathers gray. Based on a few scattered pieces of rock in

the float, it can be determined that this storm bed consists

of fossiliferous sandstone, with some very rare small-cobble

clasts. In addition to the very abundant Turritella

font

lon

SoS

—

ac,

rar)

aos

Z Cc

U me)

oO =

: je

<2 @

o WY

(a\..

Maastrichtian

Localities map and chronostratigraphy of Ravniella lipmanorum new species Squires. Ages from Gradstein et al. (2012).

peninsularis quaylei Saul, 1983, there is a diverse assem-

blage of other gastropods at this locality, as well as some

bivalves (rarely with conjoined valves), boring bivalves (in

wood), solitary corals, colonial corals ( (very rare), raninid

crabs, spiny lobster fragments, echinoid spines, and pet-

rified wood (Squires et al., in press). All these fossils were

likely swept from various relatively shallow depths by

channelized debris flows, then frapspelte -d and concen-

trated on the adjacent slope (Parker, 1981; Squires et al., in

press). Although most of the Turritella specimens consist of

only the upper spire, they are not worn nor abraded. Also,

the presence of protoconchs and delicate sculpture on

some of the gastropods is evidence that the distance of post-

mortem transport was not great. Based on concurrent

ranges of various species of Timea and other gastropods,

the onic at the Simi Valley locality are of late early Pa-

leocene age (late Danian Stage) (Squires et al., in press).

Only two specimens are known from East Fork Fish

Canyon, just west of Warm Springs Mountain area (see

Saul, 1983: fig. 13), in the lower part of the San Fran-

cisquito Formation at LACMIP loc. 21581. The fossils,

which are in black siltstone, consist of Turritella pen-

insularis quaylei and a moderate diversity of other gas-

tropods and some bivalves. Based on the presence of Tr Pp.

quaylei, the age of the rocks at this locality is the same as

for the above- emenconed LACMIP loc. 41691.

SYSTEMATIC PALEONTOLOGY

Class Gastropoda Cuvier, 1795

Subclass Heterobranchia

Grade “Lower Heterobranchia”

Infraclass Euthyneura

R.L. Squires and P. Lipman, 2018

Page 53

Cohort Acteonimorpha

Superfamily Acteonoidea d’Orbigny, 1842

Discussion: Acteonoid euthyneuran gastropods were

traditionally considered to be basal members of an

enigmatic group referred to as the shelled “opistho-

branchs” (e.g., “bubble snails”) (Kano et al., 2016). Mo-

lecular phylogeny studies, in combination with anatomical

and cladistic studies, show that “bubble snails” have

polyphyletic status (Mikkelsen, 2002). They have un-

certain systematic affinity and might have a basal place-

ment outside of the “opisthobranchs,” or they might have

an “opisthobranch” origin (Gébbeler and anes.

Kolb, 2010).

Family Acteonidae d’Orbigny, 1842

Genus Ravinella Rosenkrantz, 1970

Type Species: Cinulia danica Ravn, 1902, by original

designation; early Paleocene, Danian Stage, Denmark.

Description: Shell small sized, commonly 8 to 10 mm

height (rarely up to 13.5 mm height). Height/width ratio

1.5 to 1.8. Oval, moder rately minted to tumid. Spire

moderately low; upper spire can be tilted slightly. Spire

angle 70° to 87°. Protoconch approximately 1.5 ‘whorls,

paucispiral, smooth, heterostrophic, and coaxial. Tele-

oconch four to five whorls. Whorls convex. Suture

impressed, slightly channeled. Spiral grooves very narrow

and pitted; interspaces smooth, snerctaeatraler wide to wide.

Aperture narrow to wide; anterior end moderately narrow

to patulous.

Callus pad (inductura) along inner lip well developed

and well delineated. Anterior part of callus pad crenulate

and bearing two, commonly wide and equally to sube-

qually stout columellar plaits, both lowly to moderately

oblique, with posterior one very commonly longer. Ad-

axial end of columellar plaits commonly Srallen and

deflected backward. Parietal callus pad narrow (com-

monly) or broad; parietal-plait area extending from

medial-basal part of last whorl to low or sharp angulation,

at where callus pad bends abruptly apexward along upper

inner lip. Parietal plait short or long, nearly hor monte to

lowly oblique. At or near where bending of callus occurs,

parietal plait can be either bifurcated, or single pustule, or

small swollen area (nearly smooth). Outer lip edge thick;

subadjacent shell can be varicose. Outer lip interior

Table 1.

Species

R. “inopinata” sensu Krach, 1963

R. regularis (von Koenen, 1885)

R. rosenkrantzi (Traub, 1989)

R. lipmanorum Squires new species

R. aff. regularis (von Koenen, 1885)

R. groenlandica Rosenkrantz, 1970

R. danica (Ravn, 1902)

R.? spp. (Kiel and Bandel, 2001)

Thanetian

late Danian

early Danian

earliest Danian

Campanian

smooth or with several lirae or denticles, both becoming

obsolete anteriorward. Growth line very _ slightly

opisthocline.

Geologic Age: Campanian (questionably); late early

Paleocene (late Danian) to late Paleocene (Thanetian).

Discussion: Rosenkrantz (1970: 431) initially reported

Ravniella to be a subgenus of Tornatellaea C onrad, 1860,

a gastropod which ranges from early Middle Jurassic

(Griindel et al., 2012) to early Oligoce one (MacNeil and

Dockery, 1984), and, according to Kaim (2004: 168) is the

earliest known member of fi amily Acetonidae. Rawniella is

a genus similar to but distinct from Tornatellaea. Ravniella

has a lower spire, wider spiral angle, more tumid last

whorl, much less oblique and much stouter columellar

plaits, a parietal plait (which can be incipient), as well as

the possibility of having lirae or denticles on the interior of

the outer lip.

All the known species of Ravniella are listed in Table |

All except the new species are found only in Western

Europe or western Greenland. Ravniella danica (Ravn,

1902: 34-35, pl. 3, fig. 7; Rosenkrantz, 1970: fig. 10.1) is

from the Cerithium limestone, Stevns Klint, Denmark.

Ravniella groenlandica Rosenkrantz, 1970: fig. 10.2;

Kollmann and Peel, 1983: 105, fig. 242) is from the

Propeamussium Member (a black mudstone) of the

Kangilia Formation [now referred to as the Eqalukik

Formation, according to Dam et al. (2009)], Nugssauaq

Peninsula, central western coast of Greenland. Ravniella

regularis (von Koenen, 1885: 76, pl. 3, figs. 24a-c;

Rosenkrantz, 1970: fig. 10.4) is from Copenhagen,

Denmark. Ravniella aff. regularis (von Koenen, 1885;

Rosenkrantz, 1970: fig.10. 3) is from the Agatdal For-

mation, Sonja lens (a nner shale), Nugssuaq Peninsula,

central coast of western Greenland. Rawniella rose-

nkrantzi Traub (1989: 100-101, pl, 3, figs. 4a—b, 5a—b) is

from the Kroisbach Member of the pace part of the

Kressenberg Formation, Haunsberg area near Salzburg,

Austria. Ravniella “inopinata” Morlet (1888: 329-330, pl.

13, figs. 8-10) sensu Krach (1963: 138-139, pl. 15, figs. 4,

4a) inmedenticed by Krach, as to species] is Pom the

Babica Clays, Middle € Carpathian Mountains, southeast-

ern Poland.

Tornatellaea sp. 1 and sp. 2 of Kiel and Bandel (2001:

326, pl. Di figs. 14-17) from Upper Cretaceous (Cam-

panian) strata in northern Spain, are similar to Ravniella,

Ages and geographic distribution of known and questionable species of Ravniella.

Age Location

Southeastern Poland

early Selandian Denmark

late Danian; late Thanetian Austria

Southern California

Western Greenland

West Greenland

Denmark

Northern Spain

Page 54

THE NAUTILUS, Vol. 132, No. 2

in shape, size, sculpture, two strong columellar plaits, and

weak presence of a parietal plait. These two unnamed species,

which might be conspecific (Kiel and Bandel, 2001), are

reported here for the first time, as the earliest questionable

representative of Ravinella in the fossil record (Table 1).

Rosenkrantz (1970) did not provide a full description of

Ravniella nor did he discuss any morphologic details of the

parietal plait, especially the morphologic variation dis-

played in his illustrations (fig. 10, 1-4) of several different

species of this genus. This variation includes a_ short,

horizontal plait where the callus pad bends apexward

along the upper lip (fig. 10.1), a protuberance where the

oblique callus pad bends apexward along the upper inner

lip (fig. 10.2), a moderately long, lowly oblique, ridge-like

thickening (fig. 10.3), and a nearly horizontal angulate to

ridge- ke. thickening where the callus pad bends apex-

ward along the adapical margin of the inner lip (fig. 10.4).

Rosenkrantz (1970) also did not describe the protoconch

of Ravniella, but his sketches of Ravniella danica and

Ravniella regularis (von Koenen, 1885) show a small,

paucispiral heterostrophic protoconch (see Rosenkranz,

1970: figs. 10.1, 10.4).

Ravniella is somewhat similar to the acteonid Vasju-

gania Kaim and Beisel (2005: 57-58, fig. 15), of Maas-

trichtian age from western Siberia, Russia, in terms of

having a parietal plate in addition to columellar plaits.

Ravniella differs by having only two columellar plaits,

rather than three, a more parece last whorl, pitted spirals

with wider interspaces, lirate or dentate outer lip interior,

and a tapered anterior end of the aperture. The high,

narrow spire of Vasjugania is similar to Tornatellaea. Kaim

and Beisel (2005) reported that Acteon ringens d Orbigny

(1842: 121-122, pl. 167, figs. 13-15), from Lower Cre-

taceous Hauterivian strata in France, also be longs to

Vasjugania, and d Orbigny’ S$ species has a much Tower

spire and a more tumid last whorl, like that of Ravninella.

All these observations serve to show that the evolution of

Ravniella, Tornatellaea, and Vasjugania need further study.

Ravniella is similar also to Ringicula Deshayes, 1838,

which, according to Kaim (2014: 154-155, has been

mistakenly identified, by some authors, as Tornatellaea.

Ringicula belongs to the shell- bearing “lower hetero-

branch” family Ringiculidae Philippi, 1853, which might

have evolved from Tornatellaea-like acteonids (Kaim,

2004: 166, fig. 140). Ringicula ranges from late early

Middle Jurassic ( Callloviesny to Recents (Kaim, 2004: 156).

Ringicula, like Ravniella, also has two columellar plaits

andi a parietal plait, which is variable in its shape, but

Ringicula differs by possibly having a partially impressed

anvil protoconch whorl, commonly having a smooth

globose to subglobose shell, a lower spire, heey ily callused

inner lip, very thick outer lip (can be smooth within) that

extends more posteriorward, and a notched anterior

peristome (Sohl, 1964: 293; Kaim, 2004: 156, 169).

Rawniella resembles somewhat the euthyneuran Trip-

loca Tate, 1893, of Eocene age from Australia, but

Triploca has three columellar plaits. They are all posi-

tioned in the anterior end of the shell and are equidistantly

located, as well as being approximately the same size.

Adegoke (1973: fig. 5; 1977: 215-216, ol, BY, ines,

YD 26). illustrated an acteonid ¢ enebaba which he filet

tified as Tornatellaea (Ravniella) africana Furon, 1948 [in

Furon and Kouriatchy, 1948]. Based on its a high spire,

nearly vertical to oblique columellar plaits, absence of

a parietal plate, and no sculpture on the interior of its

outer lip, Furon’s species does not belong to Rawniella.

Ravniella lipmanorum new species Squires

(Figures 2-14)

Tornatellaea Nn. sp.—Squires et alll, in press.

Diagnosis: Ravniella with wide spire angle (80° to 86°),

narrow aperture, spiral grooves separated by much wider

areas, denticles (not lirae) on outer lip interior.

Description: Shell commonly 9 to 10 mm height and 6 to

7 mm width; (rarely up to 11.5 mm height and 6.3 mm

width); height to width ratio commonly 1.5 to 1.6 (rar ely

103) Oval cumidl: Spire moderately low: upper spire can

be tilted slightly. Height of spire less than height of ap-

erture. Spire angle 80 to 86°. Protoconch heterostrophic,

coaxial, and tilted. Teleoconch with up to approximately

four convex whorls. Suture impressed _ to slighly chan-

neled; ramp small, can be somewhat angulate. Sculpture

comprised of very narrow, incised spiral grooves, con-

tinuous, and crossed by collabral microscopic eas (growth

lines), forming cells made minutely pitted by constriction

at regular inperwale Spiral grooves separated by much

wider, flat smooth areas, niga on periphery of last whorl

and becoming narrow on neck. Aperture elongate, nar-

row, and widening slightly anteriorly. Gallins pad

(inductura) on columella area bearing two lowly oblique

plaits, equally to subequally thick (rarely thin), and

crenulate; posterior plait can extend slightly farther into

aperture. Callus pad on parietal area prominent, broad,

extending obliquely onto base of last whorl and abruptly

bending apexward to posterior end of inner lip or near

it. Parietal callus broad and can be slightly detached.

Parietal-plait area extending from medial-basal part of last

whorl to low or sharp angulation, at where callus pad

bends abruptly apexward along upper inner lip. Parietal

plait short or long, nearly horizontal to lowly oblique. At or

near where bending of callus occurs, parietal plait can be

either bifurcated, or single pustule, or small swollen area

(nearly smooth). Umbilical groove weak, partly obscured

in apertural view by the Balumnellae Outer lip interior can

be thickened and bearing approximately seven moder-

ately widely spaced denticles; exterior area adjacent to

outer lip edge can be varicose. Growth line slightly in-

clined (opisthogryral) and with small deflection near su-

ture. Growth lines can be prominent (varicate) and closely

spaced in vicinity of exterior edge of outer lip.

Holotype: LACMIP 14724, 10.6 mm height and 7.3 mm

width (protoconch incomplete), height to width ratio 1.5

(Figures 2-9).

Paratypes: LACMIP 14725-14728.

R.L. Squires and P. Lipman, 2018

“44

Figures 2-14. Ravniella lipmanorum new species Squires, LACMIP loc. Bane lower Santa Susana Formation. Specimens

whitened with ammonium chloride. 2-9. Holotype LACMIP 14724. 2. Apertural view. 3. Apertural view, closeup of spiral grooves on

upper right part of last whorl. 4. Abapertural view. 5. Left-lateral view. 6. Right-lateral view. 7. Oblique view of anterior end of last whorl.

8. Apical view. 9. Abapical view. 10. Paratype LACMIP 14725, abapertural view of last whorl of teleoconch and apertural view of

hyperstrophic protoconch. 11. Paratype LACMIP 14726, apertural view. 12. Paratype LACMIP 14727, apertural view. 13-14. Paratype

LACMIP 14728. 13. Apertural view. 14. Right-lateral view. Scale bars = 2 mim, unless othenwvise indicated.

Type Locality: LACMIP 41691. The locality, which is on

private property, was temporary. It is now covered by the

installment of landscaping and sprinklers.

Geologic Age: Late early Paleocene (late Danian).

Distribution: San Francisquito Formation, East Fork

Fish Canyon, Warm Springs Mountain, Los Angeles Co.,

southern California; lower Santa Susana Formation, just

south of Mount Sinai Memorial, north side of Simi Valley,

Ventura Co., Southern California.

Etymology: The new species is named for the Paul

Lipman family, in recognition of their discovery of the

locality and careful eallscting of specimens, which the 2y

Page 56

THE NAUTILUS, Vol. 132, No. 2

kindly donated. The senior author, Squires, is the sole

author of this new species.

Discussion: Forty-four specimens were examined, and

all, but two, are from LACMIP loc. 41691. About 20

specimens from this locality have good to very good

preservation, including presence of the protoconch. Onall

of these 20 specimens, however, the shell material of the

protoconch has been decorticated, leaving only an internal

cast showing the shape of the protoconch. This shape

matches closely with the shape of the protoconch o

Tornatellaca illustrated by Kaim (2004: figs. 132-133). /

few mature specimens of the new species from the ee Tr

Santa Susana Formation have one or two narrow radial

furrows on the last whorl, and these are secondary in

origin. The two specimens from the lower San Francis-

quito Formation have moderately poor preservation, in-

cluding absence of a protoconch.

The new species is the first occurrence of Ravniella in

the fossil record of the northeast Pacific. Compared to the

known species of Ravniella, the new species differs by

having a wider spiral angle, narrower aperture, and

denticles on the outer lip interior. Ravniella lipmanorum

is most similar to Ravniella danica (Ravn, 1902: 238-239,

pl. 3, fig. 7; Rosenkrantz, 1970: fig. 10.1) from lowermost

Danian strata in Denmark. The new species differs by

having upper spire whorls slightly tilted on some speci-

mens, callus pad on parietal area commonly wider, more

variable development of the parietal plait, and presence of

denticles rather than long lirae on the outer lip interior.

Ravniella lipmanorum is also very similar to Ravniella

groenlandica (Rosenkrantz) of Kollmann and Peel, 1983:

105, fig. 242 [= Ravniella aff. R. groenlandica Rosenkrantz,

1970: fig. 10.2] from lower Danian strata in western

Greenland The new species differs by smaller maximum

size, less tumid, wider spiral angle, narrower aperture,

narrower and not upturned eolene llar plaits, parietal-area

callus pad commonly wider, and more dentate outer lip

interior.

PALEOBIOGEOGRAPHIC CONSIDERATIONS

The early Paleocene (early Danian) occurrence of Rav-

niella in Denmark is the earliest unequivocal record of this

genus. From Denmark, the genus spread to southeastern

Poland, Austria, western Greenland, and, by the late

Paleocene, into southern California. During Paleocene

and Eocene time, the paleoclimate of the west coast of

North America was warm temperate, and during this

interval there were pulses of immigration of many

shallow-marine, thermophilic mollusks, with most arriving

from the Old World Tethyan Sea region via eectuarde

flowing currents that passed through a low: latitude seaway

in somitnerm Mexico (Squires, 1987,

Ravniella into southern California was most likely via one

of these west-trending immigration pulses in equatorial

waters. The long s@istemee f inv elven and the relatively short

duration (approximately four million years) for this dis-

persal of Ravniella argue for a planktotrophic larval stage.

2003). The arrival of

It is possible that Ravniella originated earlier, however,

during the Late Cretaceous in Spain, thereby allowing for

more time for westward dispersal. This scenario is sup-

ported by the questionable occurrence of Late Cretaceous

(Campanian) specimens of Ravniella in northern Spain.

ACKNOWLEDGMENTS

Austin Hendy facilitated access to collections and loans.

Williams Homes, Inc. gave permission for access to the

main collecting site. ihe Owta Library-Interlibrary Loan

of California State University, Northridge obtained sev-

eral copyrighted journal papers. Lindsey T. * Giowes (LACM)

provided a key reference. Claudia del Rio (Museo Argentino

de Ciencias Naturales, Buenos Aires) and Sven N. Nie sen

(Universidad Austral de Chile, Valdivia) critically reviewed

the manuscript and gave valuable comments.

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APPENDIX 1

LOCALITIES OF THE NEW SPECIES

All quadrangles listed below are U. S. Geological Survey,

7.5 minute, topographic maps.

LACMIP 21581. North of truck trail in small unnamed

canyon west of Rattlesnake Canyon, 34°3720.75°N,

118°3721.49"W, elevation 2660 feet, lower San Fran-

cisquito Formation, north side of East Fork Fish Canyon,

Los Angeles Co., southern California, Warm Springs

Mountain Quadrangle. Age: Late early Paleocene. Col-

lectors: E. H. Quayle, June, 1941.

LACMIP 41691. Temporary exposure made during

construction of Mount Sinai Road, 34°13°12.02°N,

118°40°3.63°W, elevation 1220 feet, lower Santa Susana

Formation, north side of Simi Valley, Ventura County,

southern California, Santa Susana Quadrangle. Age: Late

early Paleocene. Collectors: P. Lipman, Jacob Lipman,

R. L. Squires, 2015-2017.

THE NAUTILUS 132(2):58-64, 2018

Page 58

A new species of Calliostoma (Gastropoda: Calliostomatidae) from

Weizhou Island, South China Sea

Junlong Zhang

Peng Wei

Suping Zhang

Department of Marine Organism Taxonomy & Phyloge ny

Institute of Oceanology, C ane se Academy ‘of Sciences

Qingdao, 266071, CHINA

and

Center for Ocean Mega-Science

Chinese Academy of Sciences

7 Nanhai Road

Qingdao, 266071, CHINA

[email protected]

ABSTRACT

This paper describes and illustrates Calliostoma spesa new

species, sampled from the intertidal zone in coarse sandy

bottom in Weizhou Island, the South China Sea. The new

species is characterized by its conical shell with dense spiral

cords which are composed by strings of strong beads. We

describe the shell characters in detail end compe it with the

similar species Calliostoma basulense Poppe, Tagaro and

Vilvens, 2014. Mitochondrial 16S rRNA and nuclear 28S

rRNA genes of the new species are sequenced. Phylogenetic

trees constructed using Bayesian inference (BI) and maximum

likelihood (ML) analyses incorporating available Calliostoma

sequences from Ge Bank, confirm the generic assignment of

this taxon to a new species.

Additional Keywords: Trochoidea, Calliostoma, taxonomy,

phylogeny, 16S, 28S, Beibu Gulf

INTRODUCTION

Calliostomatidae is a basal family in Gastropoda, oc-

curring in the tropics, subtropics, temperate zones, and

polar regions, from intertidal and subtidal to several

aramenel meters deep on sandy, muddy, or rocky sub-

strates. Calliostomatids are small (a few mm) to rather

large (up to 80 mm) in size, conical, cyrtoconoidal, or

coe Slowornratidlell § in shape. Shells of members of this family

usually have strong spiral cords, usually with bead-like or

knob-like nodules or small spines on cords, a protoconch

sculptured with a network of threads forming polygonal

spaces, a convex to flat base with spiral cords, and

a corneous, subcircular operculum with a subcentral

nucleus. Marshall (2016) estimated that this family is

represented by more than 300 recent species worldwide.

According to WoRMS (World Register of Marine Species)

and MolluscaBase, about 440 recent valid species in about

30 accepted genera are on record at the time of writing

(MolluscaBase, 2018).

This family is well studied in the southwest Pacific. In

1995, Marshall conducted two rae systematic

works. A total of 30 species, including 27 new species,

from New Caledonia (Marshall, 1995a) cnt 33 species,

including 10 new species, from New Zealand (Marshall,

1995b) were studied in detail. Some of the taxa within this

group were revised, discriminated, and delimited. Since

then, great attention has been devoted to this group.

Systematic studies and new species are coming forth,

continuously, especially on species from ropicall Pacific

islands. Vilvens recorded 13 species, including 5 new, from

Vanuatu, Fiji, and Tonga (Vilvens, 2005), and 16 species,

including 7 new, from New Caledonia and the Solomon

Islands (Vilvens, 2009). Stratmann and Schwabe (2007)

described another new species, also from the Solomon

Islands. Marshall (2016) described 3 new species from New

Zealand and reported a new record from the latter islands.

The Philippines is another biodiversity hotspot for

Calliostomatidae. In total, 33 calliostomatids have been

reported from there (Poppe, 2008; 2011; 2017), with

many new species described (Bozzetti, 1997; Vilvens,

2000a; 2000b; Poppe, 2004; Poppe, et al., 2006; Poppe,

et al., 2014). In the northwest Pacific, 29 species are

recorded from Japan (Sasaki, 2017). Despite the lack of

extensive studies covering Chinese waters, Dong (2002)

conducted systematic studies on the superfamily Tro-

choidea of China. He reported only 11 species from 2

genera within the Calliostomatidae, including 2 new to

science. Fu (2007) reported 8 species from Taiwan. Zhang

(2008) recorded 12 species and 2 genera from Chinese

J. Zhang et al., 2018

Page 59

seas. Huang and Fu (2015) described 2 new species from

Taiwan and the Yellow Sea. Most numbers of this family in

China are distributed in the East China Sea and South

China Sea, except 3 living in the Bohai Sea and Yellow Sea.

There should be more species waiting for their discovery.

Recent phylogenetic studies of the Calliostomatidae

supported by morphological and molecular studies accept

the inclusion of five subfamilies (Williams, 2012: Marshall,

2016). But the relationships at the generic level have not

yet been well defined, most likely See of extensive

variations in shell morphology and inadequate sampling

for thorough genetic studies. Many genera or subgenera

have been erated or separated for the type genus

Calliostoma Swainson, 1840. But some are not widely

accepted or are still in dispute. Accordingly, quite a few

species, including some recently describe a are lumped in

the genus Callbostonvn. when it is clear that they should

belong in a different genus-level taxon. Although more

and more species within Calliostoma have been discov-

ered since 1995, genetic information is still insufficient to

solve the generic relationships.

Specimens of two individuals were collected in May 2016,

from the intertidal zone of Weizhou Island, located in the

Beibu Gulf, South China Sea, under the jurisdiction of

Guangxi Zhuang Autonomous Region, China. Our initial

sindiewindhonien dnet ines samples| belong to a new species.

MATERIALS AND METHODS

Two individuals of the new species were collected. The

larger one was well-developed empty shell, here assigned

as the holotype of the new species. The smaller one was

sampled alive, preserved in 70% ethanol for molecular

analyses, and is here designated as the only paratype of the

new species. Shells were robisery ed under light microscopy

and photos were taken using a Cannon E OS6D camera.

Images of the protoconch were captured under a Zeiss

Discovery V12 stereo microscope using a Zeiss AxioCam

503 digital camera. Measurements were made with

a vernier Caliper to the nearest 0.1 mm. Spiral cords on

shell are numbered consecutively adapically to abapically

following Ikebe (1942), Mar shall (1988) and Vilvens

(2009).

Total DNA was extracted using the Marine Animal

Genomic DNA Extraction Kit (Tiangen Biotech, Beijing,

Table 1. List of species and their GenBank accession numbers of sequences used in present study.

Calliostoma

Species

aculeatum Sowerby III, 1912!

akoya (Kuroda in Ikebe, 1942)

antonii (Koch in Philippi, 1843)

consors (Lischke, 1872)!

granulatum (Bom, 1778)

granti (Powell, 1931)

haliarchus (Melvill, 1889)!

iridium (Dall, 1896)

javanicum (Lamarck, 1822)

jujubinum (Gmelin, 1791)

kiheiziebisu (Otsuka, 1939)?

ligatum (Gould, 1849)

multiliratum (Sowerby I, 1875)

punctulatum (Martyn, 1784)

shinagawaense Tokunaga, 1906°

tigris (Gmelin, 1791)*

torrei Clench & Aguayo, 1940

unicum (Dunker, 1860)°

waikanae (Oliver, 1926)?

zizyphinum (Linnaeus, 1758)

spesa new species

Margarella antarctica (Lamy, 1905)

Margarella biconica (Numanami, 1996)

Margarella crebrilirulata (Smith, 1907)

Margarella refulgens (Smith, 1907)

28S rRNA

16S rRNA

AB505225 AB505316

AB505226 AB505317

GQ160645 GQ160691

GQ232378 GQ232281

EU530015 z

GQ232388 GQ232289

2 DQ093478

GQ249711 2

AB505227 AB505318

GQ232380 GQ232283

EU530014 a

GQ232381 =

AB505228 AB505319

GQ232383 GQ232285

AB505229 AB505320

GQ249708 GQ249817

= GQ249820

AB505230 AB505321

GQ249709 GQ249818

= DQ314294

s KY671200

AB505231 AB505322

GQ249710 GQ249821

EU530016 a

2 KY200894

MH444454 MH444453

GQ232398 =

HE800692 HES800741

HES00693 HES800742

HES00694 HES800743

' Belongs to the genus Tristichotrochus Ikebe, 1942 (fide WoRMS, 2018)

Belongs to the genus Otukaia Ikebe, 1942 (fide WoRMS, 2018)

> Belongs to the genus Tristichotrochus Ikebe, 1942 (fide WoRMS, 2018)

* Belongs to the genus Maurea Oliver, 1926 (fide WoRMS, 2018)

Page 60

THE NAUTILUS, Vol. 132, No. 2

China). Fragments of the mitochondrial 16S rRNA gene

were amplified using 16Sa: 5’/-CGC CTG TTT ATC AAA

AAC AT-3’ (Xiong and Kocher, 1991), 16Sb: 5’-CTC CGG

TTT GAACTC AGA TCA-3’ (Edgecombe, Giribet, and

Wheeler, 2002). The nuclear 28S rRNA gene was am-

plified using 28S-D1F: 5’-GGG ACT ACC CCC TGA

MIM? IAA GCA I8),, BES-IDERs SCA GCP ATC Cire

AGG GAA ACT TCG-3’ (Park and O Foighil, 2000). The

25-wL reaction for the amplification contained 12 pL

2xXEs TaqMasterMix (CWBio Co., Ltd, Beijing, China),

2 wL of template DNA (50 ng/L), 1 wb of each primer

(10 M) and 9 wL dH,O. Amplification reactions were

conducted in a T100 Thermal Cycler (Bio-Rad Labora-

tories, Inc.) with the following thermal profile: 95°C for 3

min; 35 cycles of 95°C for 30 s, 48-52°C for 45 s, 72°C for

1 min, and a further 10-min elongation at 72°C. The PCR

products were purified and sequenced by BGI Tech

Solutions Co., Ltd. One partial 16S sequence and one

28S sequence were obtained and have been deposited

in GenBank. For phylogenetic analyses, some of the

0.1 mm

Figures 1-7. Calliostoma spesa new species. 14. Holotype, MBM229029. 1. Apertural view. 2. Dorsal view. 3. Adapical view. 4.

Protoconch. 5-7. Paratype, XSM unnumbered. 5. Apertural view. 6. Dorsal view. 7. Paratype, alive.

J. Zhang et al., 2018

>, +6

Page 61

sequences used here were retrieved from GenBank (see

Table 1). Species of Margarella, subfamily Margarellinae

Williams, 2013 were selected as Seen Paes

were aligned independently using MAFFT v.7 (Katoh and

Standley, 2013) with the G-INS-i ‘ecm for the

protein- “coding and ribosomal regions. Maximum likeli-

hood (ML) analysis was carried amt using RAxML 8.1.2

(Stamatakis, 2014) (with bootstrapping) using GTR+G+1

Calliostoma_tigris_GQ249818.1

Calliostoma_waikanae_GQ249821.1

Calliostoma_punctulatum_GQ249817.1

as the model for each partition on combined data.

Bayesian inference was done using the software Mr Bayes

BEAG (Ronquist et al., 2012). Meshes were run for 10

million generations using four chains with a sampling

frequency of 1/1000 trees. Four inde “pe sndent MCMC

runs, each starting with random trees for each of four

simultaneous chains, gave nearly the same results. Results

were visualized using FigTree v. 1.4.3. Acronyms and

Calliostoma_granulatum_DQ093478.1

Calliostoma_zizyphinum_KY200894.1

Calliostoma_torrei_KY671200.1

Calliostoma_torrei_DQ314294 1

Calliostoma_antonii_GQ160691.1

1/100

Calliostoma_antonil_GQ232281.1

Calliostoma_indium_GQ232283.1

Calliostoma_spesa_sp__nov.

Calliostoma_hatliarchus_AB505318.1

App ea multiiratum_AB505320. 1

Calliostoma_consors_GQ232289.1

Calliostoma_shinagawaensis_AB505321.1

Calliostoma_aculeatum_AB505316 1

Calliostoma_unicum_AB505322.1

4/1007] 0.52/99

Calliostoma_punctulatum_GQ249820.1

0.66/47

1/100

0.63;

0.94/56

0.68

0.98/91

0.51/90

1/56 a

0.98/7p

0.79/

Calliostoma_ligatum_GQ232285.1

Calliostoma_kiheiziebtsu_AB505319.1

0.79/

Calliostoma_akoya_AB505317.1

Margareila_refulgens_HE800743.1

0.57/66

Margarella_crebniirulata_HE800742

1/100

Margarella_biconica_HE800741.1

0.07

Figure 8.

Phylogenetic tree inferred by Bayesian analysis (BI) and maximum likelihood (ML) from the mitochondrial 16S rRNA gene.

Numbers adjacent to nodes refer to BI posterior probability (PP) and ML bootstrap scores (BS). Node value only show with BS > 50 and PP >

0.50.

Page 62

THE NAUTILUS, Vol. 132, No. 2

abbreviations used throughout the text are: MBM: Marine

Biological Museum, Chinese Academy of Sciences,

Qingdao; XSM: Xiangri Shell Museum, Rizhao, China: P1,

P2, P3,...: Primary Sore (P1 is the most adapical); $1, $2,

$3,...: Secondary cords (S1 is the most adapical).

SYSTEMATICS

Order Vetigastropoda Salvini-Plawen, 1980

Superfamily Trochoidea Rafine ae 1815

Family Calliostomatidae Thiele, 1924 (1847)

1/90

1/100

Margaretia_refuilgens_HE800694 1

M#£rgarella_crebdniirulata_HE800693.1

Margareila_biconica_HE800692.1

Margarella_antarctica_GQ232398 1

0.02

Figure 9.

Genus Calliostoma Swainson, 1840

Type Species: Trochus conulus Linnaeus, 1758 (by

subsequent designation of Herrmannsen, 1846)

Calliostoma spesa new species

(Figures 1-7)

Description: Shell small, §.8-10.1 mm_ in length,

7.7-8.5 mm in width, conical in shape, solid. Spire high,

Tyas whorl large. Protoconch of 144 whorls, sculptured

with network att threads that enclose hexagonal spaces.

Calijostoma_kiheiziebisu_AB505228 1

Calliostoma_akoya_A8505226 1

Calliostoma_ligatum_GQ232383.1

Calliostoma_consors_GQ232388.1

Calliostoma_consors_EU530015.1

Cailiostoma_multiliratum_AB505229 1

Calliostoma_haliarchus_AB505227.1

Calliostoma_unicum__A8505231.1

Calliostoma_shinagawaensis_AB505230, 1

Calliostoma_aculeatum_A8505225.1

Calliostoma_granti_GQ249711.1

Cathiostoma_waikanae_GQ249710.1

0.97/

Calliostoma_punctulatum_GQ249708.1

Calliostoma_tigris_GQ249709.1

Calliostoma_jujubinum_GQ232381.1

1/98

Calliostoma_javanicum_EU530014.7

Calliostoma_inidium_GQ232380.1

GQ232378.1

Cailiostoma_antonii_

Cailiostoma_antonii_GQ160645.7

Calliostoma_zizyphinum_EU530016.1

Calliostoma_spesa_sp._nov

Phylogenetic tree inferred by Bayesian analysis (BI) and maximum likelihood (ML) from the nuclear 28S rRNA gene. Numbers

adjacent to nodes ee to BI posterior probability ( (PP) and ML bootstrap scores (BS). Node value only show with BS > 50 and PP > 0.50.

J. Zhang et al., 2018

Teleoconch of 8-9 whorls. Suture visible, thin, slightly

constricted. First whorl weakly convex, almost flat; next

whorls more convex, with a weak peripheral keel. Shell

surface sculptured with dense spiral cords composed of

strings of strongly beaded nodules. Interspace between

the spiral cords thin and deep, irregularly spaced, smaller

than cords. Each whorl with 5-6 spiral cords, including

two stronger cords with thick beads at periphery. First

Relsoconen whorl with 3 cords, P2 and P3 appearing

immediately, P1 appearing a quarter of whorl later; spiral

cords with “granular” aspect caused by intersection with

axial threads, aspect evenly spaced on entire whorl; P1

weaker than other cords: $3 completely hidden by suc-

ceeding whorl. On second whorl, P1 as strong as P2, P3

strongest; $3 appearing above suture. On teal sino P3

strongest, S3 thickening, almost as strong as P] and P2,

but less strong than P3; $2 appearing at end of whorl, very

thin. On Fourth whorl, $3 thickening stronger than P1 and

P2, but still less strong than P3; $2 thin ararels weak; beads on

Pl, P2 and P3 sharper than on $3. On next whorl, $3

strongest, forming keel; P1, P2 and $2 more or less similar

in strength, with P3 stronger than them; beads of P1, P2

S2., and P3 triangular sharp; beads of S3 blunt; S]

appearing at end ae whorl, very thin. On last whorl, S1

fully visible, granular but weaker than other cords: other

spiral cords Almost similar in size. Aperture broad, sub-

quadrate; collumella curved, concave. Outer lip thin, with

crenulated incision on margin. Inner lip slight thick,

columellar lip smooth and nacreous. Anomphalous. Base

flat, with about 9 weakly subgranular spiral cords of even

thickness, interval between yaar thin and deep. Shell

purplish-red in color, spotted with irregular yellowish or

brownish blotches. Color of beads on cords various cov-

ered by white and brown splotches or white and red

splotches. Operculum corneous, yellowish, subcircular,

multispiral, with subcentral nucleus.

Type Material: Holotype MBM229029 (length 10.1,

width 8.5 mm), deposited in the MBM. Paratype (length

8.8 mm, width 7.7 mm), deposited at the XSM collection,

unnumbered.

Type Locality: Weizhou Island, Guangxi Zhuang Auton-

omous Region, China, intertidal zone, coarse sandy bottom.

Distribution: Known only from the type locality.

Etymology: The specific epithet spesa was inspired by

the Latin word spes, meaning hope. It is not used here as

a formal derivation of that Latin word, but as a freely

conceived name in apposition. The Type Material was

collected by Chinese shell collector Mr. Xi Chen, whose

nickname is “Hope”.

Remarks: The new species is morphologically similar to

Calliostoma basulense Poppe, Tagaro, and Vilvens, 2014,

but the new species can be distinguished by the weak

peripheral keel, strong beads at spiral cords, and deep thin

interspaces between dhe spiral cords. Calliostoma basu-

lense has flat, non-convex whorls, weaker nodules at spiral

cords, and shallower interspaces.

Page 63

Molecular Analyses: One sequence of the mitochondrial

16S rRNA and one of nuclear 28S rRNA genes were

obtained from the new species. In the present study, we

include available Calliostoma sequences from Ge nBank

and species of subfamily Margarellinae Williams, 2013 as

the outgroup. For each. gene, ne resulting two consensus

trees established using BI and ML analyses were generally

consistent; thus, a single topology was presented with

support values aeiented on branches (Figures 8 and 9).

The phylogenetic trees show that Calliostoma spesa new

species belongs i in the Calliostoma clade but is genetically

different Ronn other species of Calliostoma abate d from

GenBank. Species of genera Calliostoma and Margarella

representing the subfamilies of Calliostomatinae and

Margarellinae form two well-supported clades, respec-

tively. Some species of Calliostoma used in present study,

are assigned into different genera by WoRMS (see

Table 1 1). But neither the 16S nor 28S phyloge netic trees

support those allocations. Under current circumstances,

the new species is placed within the genus Calliostoma.

But, we cannot speak of its relationships with other

species, in particular with those discovered from tropical

Pacific, because most of the species were described

mainly via shell morphology characters. There is a large

number of species in this genus, but little information

based on molecular data. mnie genetic information on this

new species will hopefully help resolve phylogenetic re-

lationships and generic allocations in the Fate

ACKNOWLEDGMENTS

This research was supported by the Special Funds for the

Young Scholars of Taxonomy of the Chinese Academy of

Sciences (No. ZSBR-009) and the National Natural Sci-

ence Foundation of China (No. 31772422).

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THE NAUTILUS 132(2):65-69, 2018

Page 65

Rediscovery of Cadulus podagrinus Henderson, 1920:

redescription, new records from the Bahamas, and discussions

of its taxonomy (Scaphopoda: Gadilida: Gadilidae)

Leonardo S. Souza

Museu Nacional, Universidade Federal do Rio de Janeiro

Quinta da Boa Vista, SA0 Cristovao

Rio de Janeiro, RJ, 20940-040, BRAZIL

[email protected]

Carlos Henrique S. Caetano

Universidade Federal do Estado do Rio de Janeiro

Av. Pasteur, 458, Urea

Rio de Janeiro, RJ, 22290-240, BRAZIL

[email protected]

ABSTRACT

Cadulus podagrinus Henderson, 1920 is reported from deep

waters off the Bahamas, the first record since its original de-

scription. This new record of C. podagrinus Bonde d the

geographic distribution of the species northward by about

2,000 kin. This species bathymetric distribution is also extended

from 219 m to 465 m depth. The species is redescribed and the

synonymy between C. podagrinus and its junior synonym

Cadulus halius Henderson, 1920 is discussed.

Additional Keywords: shell morphology, morphometry, Cadulus

halius

INTRODUCTION

Steiner and Kabat (2004) catalogued 517 extant and 816

extinct species of Scaphopoda, which is one of the smaller

molluscan classes. The systematic and relationship of su-

prageneric groups of the class is relativ ely well known, with

two orders recognized: Dentaliida and Gadilida (Reynolds

and Steiner, 2008 and references cited therein).

Taxonomic revisions of the class were done for the

Indo-Pacific fauna (Scarabino, 1995; Lamprell and Healy,

1998) and for the Atlantic Ocean fauna (e.g., Henderson

1920: Caetano et al., 2006, Scarabino and Caetano, 2008;

Caetano et al. 2010; Scarabino and Scarabino, 2011).

According to Scarabino and Scarabino (2011), about 130

species occur in the Atlantic Ocean, with 90 of them

present in the western Atlantic. Henderson (1920) pub-

lished the first comprehensive revision of scaphopods

from the western Atlantic and, since then, the number of

species in this area remained relatively stable (Scarabino

and Scarabino, 2011).

Henderson (1920) studied more than 70 species of

Scaphopoda, of which 50 were described by him as new.

Steiner and Kabat (2004: 555) stated that “This study led

John B. Henderson to be one of the most prolific authors

of Scaphopoda”. About half of the species described by

Henderson (1920) were classified in Cadulus Philippi,

1844. However, since Henderson’s work the concept of

Cadulus changed substantially, with numerous of his

original sections or subgenera being elevated to genus

status (see Palmer [1974] for details). Currently, the genus

Cadulus has a worldwide distribution, with records since

the Cretaceous, and occurring from the continental shelf

to abyssal depths. The shell in this genus is characterized

by having small to medium size (2- 6 mm long), swollen

appearance, maximum diameter in the center, a solid,

smooth surface, color white when dead or translucent

when fresh (Scarabino, 1995). The apertures are usually

dorsoventrally or laterally compressed, the apex is simple

or coronate, the preapical callus commonly prominent

and the lumen is commonly circular (Scarabino 1995).

Cadulus podagrinus Henderson, 1920 was described

based on three specimens, all of them collected from the

type locality, off English Harbor, Antigua, 120 fathoms

[equivalent to 219 m depth]. From the same sample,

Henderson (1920) also described Cadulus halius. Steiner

and Kabat (2004: 631-632) stated that C. halius

Henderson, 1920 as a junior synonym of C. podagrinus,

by first reviser action (ICZN 1999, article 24). According

to the latter authors the holotypes of C. podagrinus And

C. halius differ by the le ngth between the dorsal aper-

ture and the location of eh maximum diameter, which

could merely reflect the difference in the length of the

specimens. Cadulus podagrinus is known only from its

type locality.

Recently, examination of material deposited in mala-

cological collections revealed new records of C. poda-

grinus, which represents a rediscovery of the species after

almost a century. The shells ide ntified provide new ma-

terial to reassess the synonymy between C. podagrinus

and C. halius.

MATERIALS AND METHODS

This report is based on specimens from the malacological

collection of the Academy of Natural Sciences of Phila-

delphia, Drexel University (ANSP). Types of C. podagrinus

DY > BG

Page 66

THE NAUTILUS, Vol. 132, No. 2

Figures 1-6. Cadulus podagrinus Henderson, 1920. 1-4. C. podagrinus, Holotype USNM 596597. 5-6. Cadulus halius Henderson,

1920, Holotype USNM 596599. 1, 5. Shell in lateral view. 2, 6. Shell in frontal view. 3. Detail of posterior aperture. 4. Detail of anterior

aperture. Scale bars: 1-2, 5-6 = 1.0 mm; 3-4 = 200 pm.

Henderson, 1920 and Cadulus halius Henderson, 1920

housed at Smithsonian Institution’s National Museum of

Natural History (USNM) were also examined. The _ re-

description of C. podagrinus is based on the amount of

specimens identified. Descriptive terms of shell morphology

are those of Scarabino (1995), who adopts a traditional view

in that the apertures are the most anterior (“mouth” or

anterior aperture) and postenior (“apex” or posterior aper-

ture) regions. The material consist exclusively of empty shells

and in the material examined number insided brackets in-

dicate number of shells.

To aid the morphological study, morphometric vari-

ables were measured through photographs, following

most of the variables used by Caetano et al. (2010). The

following morphometric variables were used: shell length

(L), maximum diameter (Max), distance of the point of

maximum diameter from the anterior aperture (Dmax),

height of anterior aperture (Ha), width of anterior aperture

Figures 7-11. Shells of Cadulus podagrinus Henderson, 1920 collected off the Bahamas, all in lateral view. 7-8, 10. ANSP 368515.

9. ANSP 368229. 11. ANSP 369596. Scale bar: 1.0 mm, all specimens at same scale.

L.S. Souza and C.H.S. Caetano, 2018

Page 67

0.10

(@)

f e ®

0.05

. @

0.00 . >

&d |_|

a, © ee A

60.054

[e¥)

0.104 e@

: e

-0 155

-0 Al T T T mall TT T T —T +

-0.20 -0.15 -0.10 -0.05 0.00 0.05 0.10 0.15 0.20 0.25

PC 1

Figure 12. Principal Component Analysis of the shell morphometric data. Square= holotype of Cadulus podagrinus Henderson,

1920; Triangle= holotype of Cadulus halius Henderson, 1920; Dots= shells of Cadulus podagrinus from Bahamas.

(Wa), height of apex/posterior aperture (Hp), width of apex/

posterior aperture (Wp). Variables related with curvature

were not used because this species is only minimally curved.

The morphometric data was log transformed and

a Principal Component Analysis (PCA) was performed

using PAST3 (Hammer et al, 2001) to evaluate the

variation of the morphometric maples

SYSTEMATICS

Order Gadilida Starobogatov, 1974

Family Gadilidae Stoliczka, 1868

Genus Cadulus Philippi, 1844

Type Species: Dentalium ovulum Philippi, 1844, by

monotypy. Recent, Mediterranean sea.

Table 1.

Measurements (in mm) of specimens examined in this study. SD = Standard Deviation; Min = minimum; Max =

Cadulus podagrinus Henderson, 1920

(Figures 1-11)

Cadulus (Cadulus) podagrinus Henderson, 1920: 148,

pl. 20, fig. 5

Cadulus (Cadulus) halius Henderson, 1920: 149, pl. 20,

fem l2e

Redescription: Shell up to 5.63 mm long, 1.38 mm

wide, maximum diameter close to equator; translucent,

glossy. In lateral view, ventral side is regularly curved until

near ‘the apex, region close to the apex is almost str aight;

dorsal side sinuous, alternating slightly concave and con-

vex contours. In dorsal view, region close to anterior ap-

erture has almost straight contour and is elongated; central

region is convex, regularly curved; region close to posterior

aperture almost straight in contour and elongated. Apex

maximum.

For abbreviation of morphometric variables, see Materials and Methods.

C. podagrinus

ANSP, from Bahamas (n=24)

C. halius

Holotype USNM 596597 Mean

IL 4.37 3.80

Max 1.35 B22,

Dmax 2.55 2.20

Ha 0.67 0.58

Wa 0.43 0.49

Hp 0.43 0.36

SD (+) Min—Max Holotype USNM 596599

0.19 3.40—4.05 5.63

0.07 1.06-1.38 1.31

0.13 ].83-2.44 2.9]

0.03 0.51—0.63 0.72

0.05 0.38—0.56 0.47

0.03 0.32-0.42 0.42

0.02 0.40-0.49 0.46

Wp 0.52 0.44 02 7 5

Page 68

THE NAUTILUS, Vol. 132, No. 2

Table 2. Summary table of PCA analysis of the morphometric

data of Cadulus podagrinus. PC= Principal Component.

PCs Eigenvalues % variance

] 0.004383 14 50.71

2 0.00226973 26.259

3 0.000963595 11.148

4 0.000400395 4.6323

5 0.000365373 4.297]

6 0.000205637 2.3791

5,56E +00 0.64368

wide, oval, compressed dorsoventrally, bilobed, one lobe

in ventral side and other in dorsal side. Preapical callus

thin, lumen dorsoventrally oval. Anterior aperture wide,

oval, laterally compresse od, oblique in lateral view.

Type Locality: Off English Harbor, Antigua, 120

fathoms [equivalent to 219 m depth], State University of

Iowa Expedition, sta. 115, 1918.

Type Material: Holotype: USNM 596597; Para-

types: USNM 596598 [1], USNM 314935 [2], both from

type locality. Cadulus halius: Holotype: USNM 596599,

off English Harbor, Antigua, 219 m depth, State Uni-

versity of Iowa Expe sdittionn sta. 115, 1918; paratypes:

USNM 314936 [5], from type locality (same type locality

as Cadulus podagrinus ).

Material Examined: Holotype of C. podagrinus:

Holotype of C. halius. Bahamas (all originally as Cadulus

sp.): Memory Rock, Grand Bahama aber (26°57 N,

79°06’ W, 464 m depth), coll. Rose, B.: ANSP 368229 [4];

Wood Cay, Grand Bahama Island (26°44'15"N

79°58'15"W, 465 m depth), coll. Rose, B.: ANSP 369596

[15]; West End, Grand Bahama Island (26°42'15’N

78°59'50"W, 305 m depth), coll. Rose, B.: ANSP 368515 [5].

Measurements: see Table 1 and Appendix 1.

Distribution: Bahamas (this study); Antigua and Bar-

buda (Henderson 1920). Empty shells occuring from

219 m (Henderson 1920) to 465 m depth (this study).

Remarks: The shells from Bahamas identified here

match the morphology of the holotype of C. podagrinus

(Figures 1-4), showing an inflated shell, very convex in the

central region, and eatin ihe region close to dorsal aperture

shorter and straight (Figures 7-11). The holotype of C.

halius (Figures 5-6) has the region close to dorsal

aperture more elongated than the holotype of C.

podagrinus (Figures 1-2) and than the Bahamian

specimens (Figures 7-11). We have not found any in-

termediate stage of growth between the types of C.

podagrinus aril (Ge Irealins.

Despite the difference of more than 1.0 mm in shell

length between the types of C. podagrinus and C. halius

(Table 1), the maximum diameter (Max) and dimensions of

apertures (Ha, Wa, Hp, Wp) present smaller differences

in these shells (Table 1). In Scaphopoda, during growth

the mantle margin secretes the shell in both apertures. In

the posterior aperture, shell absorption occurrs to keep the

aperture open for metabolic activities (e.g., water circula-

tion, gas exchange) (Palmer and Steiner, 1998). Thus,

during growth the posterior aperture can remain with

a similar dimension, which can explain these small differ-

ences of Hp and Wp.

The component | and component 2 of the PCA explain

50.7% and 26.3%, respectively, of the variation of the sam-

ple, that is 77% of the variation (Table 2). At the component

1, the variables L and Dmax explain most of the variation

(Table 3). The holotypes of C. podagrinus and C. halius

show the highest scores in the component 1, more distant

from the remaining shells. This can be explained by the size-

effect, as both show the highest values of L and Dmax, the

remaining shells are younger specimens.

Despite these assumptions, we remain skeptical about

the proposed synonymy between C. podagrinus and C.

halius. A greater number of specimens of similar size to

the holotype of C. halius would be useful to investigate the

late ontogeny of the species and reassess the synonymy of

these names.

The most similar species in the Atlantic is Cadulus

nerta Caetano, Scarabino and Absalao, 2006, however,

as noted by Caetano et al. (2006) “it is less inflated,

smaller and has a more laterally compressed apertural

section’.

The new record of C. podagrinus in Bahamas (+26°N)

represent a rediscovery of the species after almost

a century (Henderson 1920) and extends northward the

geographic distribution of the species. Cadulus poda-

grinus was known only from the type locality (=17°N).

The bathymetric distribution is also extended from 219 m

to 465 m depth. The species is known only by empty

shells.

Table 3. Component loadings for each morphometric variable of Cadulus podagrinus.

PC 1 RE PC 3

IL, 0.58336 -0.12312 0.24622

Max 0.30608 0.23067 0.031113

Dimax 0.50882 -0.18827 0.26826

Ha 0.32915 -().24857 0.1539

Wa -0.013899 0.80716 0.53351

Hp 0.37359 0.37475 -0.6283

Wp 0.2429 ().20603 -0.40418

PC 4 PC 5 PC 6 Rw

-0.24915 -0).24491 0.26841 -0.62434

0.4668 0.54188 -0.4688 -0.34761

-0.40903 0.19302 -0.34136 0.55911

0.73059 -0.21471 0.32336 0.34895

-0.010881 -0.12281 0.15423 0.15707

0.0086704 -0.49668 -().25863 0.10757

-0.13697 0.54886 ().62962 0.13697

L.S. Souza and C.H.S. Caetano, 2018

Page 69

ACKNOWLEDGMENTS

We are grateful to P. Callomon and N. Phillips (ANSP), E.

Strong, and Y. Villacampa (USNM) for support during the

visit of to the collections under their charge; to A. Kabat

(MCZ) and G. Steiner (Universitit Wien) for the revisions

that improved the manuscript. We are indebted to our

friends C. Galvao and G. Miranda for hosting the senior

author for the duration of his research visit to the USA.

The senior author also thanks CNPq (Conselho Nacional

de Desenvolvimento Cientiffico e Tecnol6gico, Brazil) and

JAPES (Coordenagao de Aperfeigoamento de Pessoal de

Nivel Superior, Brazil) for a graduate studies scholarship

(CN Pq/MCTI/FAP/PROTAX #001/2015).

LITERATURE CITED

Caetano, C.H.S., V. Scarabino, and R. S. Absalao. 2006.

Scaphopoda (Mollusca) from the Brazilian continental

shelf and upper slope (13° to 21°S) with descriptions of

two new species of Cadulus Philippi, 1844. Zootaxa

1267: 1-47.

Caetano, C.H.S., V. Searabino, and R. S. Absalao. 2010. Brazilian

species of Gadila (Mollusca: Scaphopoda: Gadilidae):

rediscovery of Gadila elongata comb. nov. and shell mor-

phometrics. Zoologia (Curitiba) 27(2): 305-308.

Hammer, @., D.A.T. Harper, and P.D. Ryan. 2001. PAST:

Paleontological Statistics software package for educa-

tion and data analysis. Palaeontologia Electronica 4(1):

9 pp.

Appendix 1.

Lot L

Holotype of C. podagrinus USNM 596597 4.37

Holotype of C. halius USNM 596599 5.63

ANSP. 368229 3.96

ANSP. 368229 3.56

ANSP. 368229 3.73

ANSP. 368229 3.67

ANSP 368515 3.70

ANSP. 368515 Bom

ANSP. 368515 3.84

ANSP. 368515 3.40

ANSP 368515 3.48

ANSP 369596 3.80

ANSP 369596 3.97

ANSP 369596 3.99

ANSP. 369596 3.77

ANSP 369596 3.91

ANSP 369596 3.67

ANSP. 369596 4.05

ANSP. 369596 3.52

ANSP. 369596 3.77

ANSP. 369596 4.03

ANSP 369596 3.78

ANSP. 369596 3.90

ANSP. 369596 3.86

ANSP 369596 4.02

ANSP. 369596 4.02

Max

B35

S © CO

D~IW Cl

Ios See SSeS ee Ee See eee eee ee wee we

Ko) Wo)

WNNWNNNNY

(Oo)

Henderson, H. 1920. A monograph of the East American sca-

phopod mollusks. United States National Museum Bulletin

itis W=I77/,, 220) pls.

ICZN [International Commission on Zoological Nomenclature |.

1999. International Code of Zoological Nomenclature, 4th

edition. The International Trust for Zoological Nomen-

clature, London, xxix+306 pp:

Lamprell, K.L. and J.M. Healy. 1998. A revision of the Sca-

phopoda from Australian waters (Mollusca). Records of the

Australian Museum Supplement 24: 1-189.

Palmer, C.P. and G. Steiner. 1998. Class Scaphopoda. In: P.L.

Beesley, G.].B. Ross, and A. Wells (eds.). Mollusca: The

southem synthesis. Fauna of Australia. Vol. 5. CSIRO

Publishing, Melbourne, Australia, pp. 431-450.

Reynolds, P.D. and G. Steiner. 2008. Scaphopoda. In: W.F. Ponder

and D.R. Lindberg (eds.). Phylogeny and evolution of the

Mollusca. University of Califomia Press, pp. 143-161.

Scarabino, V. and F. Scarabino. 2011. Ten new bathyal and

abyssal species of Scaphopoda from the Atlantic Ocean. The

Nautilus 125: 127-136.

Scarabino, V. 1995. Scaphopoda of the tropical Pacific and In-

dian Oceans, with descriptions of 3 new genera and 42 new

species. In: P. Bouchet (ed.). Résultats des campagnes

MUSORSTOM, vol. 14. Mémoires du Muséum national

d Histoire naturelle 167: 189-379.

Scarabino, V. and C.H.S. Caetano. 2008. On the genus

Heteroschismoides Ludbrook, 1960 (Scaphopoda: Gadilida:

Entalinidae), with descriptions of two new species. The

Nautilus 122: 171-177.

Steiner, G. and A.R. Kabat. 2004. Catalog of species-group

names of Recent and fossil Scaphopoda (Mollusca). Zoo-

systema 26: 549-726.

Raw data of shell morphometric variables of Cadulus podagrinus Henderson, 1920.

Dmax Ha Wa Hp Wp

2.55 0.67 0.43 0.43 0.52

2.91 0.72 0.47 ().42 (0.46

2.35 0.58 0.48 0.35 0.42

DMI 0.56 0.55 0.34 0.43

2.05 0.56 0.55 0.36 0.46

2.21 0.61 0.41 0.32 0.40

DMG 0.59 0.45 0.34 0.44

2.09 0.60 0.47 0.37 0.44

2.20 0.57 0.49 0.34 0.42

1.83 0.58 0.52 0.34 0.41

2.09 0.51 0.49 0.35 0.42

2.28 0.59 0.47 0.34 0.44

2.30 0.57 (0.46 0.32 0.45

DB 0.56 0.45 0.34 0.45

DNS 0.59 0.47 0.38 0.44

2.32 0.60 0.51 0.35 0.41

2.10 0.59 0.38 0.34 0.41

Dow 0.63 0.50 0.35 0.45

1.99 0.52 0.50 0.40 0.46

2.19 0.60 0.52 0.33 0.44

2.34 0.58 0.50 0.33 (0.46

2.21 0.57 0.43 0.37 0.49

2.14 0.59 0.56 0.41 0.47

D..7/ 0.59 0.49 0.37 0.47

2.28 0.54 0.55 0.42 0.48

2.44 0.57 0.55 0.39 0.46

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