New species of scissurellids from the Austral Islands, French Polynesia, and the Indo-Malayan Archipelago (Gastropoda: Vetigastropoda: Scissurellidae, Anatomidae, Larocheidae)

2008·8.6 MB·English

THE NAUTILUS 122(4):185-200, 2008 Page 185
New
species of scissurellids from the Austral Islands, French
PoKiiesia, and the Indo-Malayan Archipelago (Gastropoda:
\ etigastropoda: Scissurellidae, Anatomidae, Larocheidae)
Daniel L. Geiger
Santa Barbara Museum ofNatural Histon'
In\ertebrate ZoologN'
2559 Puestadel Sol'Road
Santa Barbara, CA93105 USA
geigerS'Netigastropoda.com
ABSTRACT ./: three genes (Ilistone 3, COI, 18S) recovered in some of
his analyses a clade rniiting all three of these lineages
FournewspeciesofScissurellidae, .Vnatomidae. and Larochei- (LcpctiHlrihis. Siiiczona, Anatoma). Scissurellidae and
dae are described from the Austral Archipelago, French
PoKnesia and the Indo-M;ila)'an Archipelago: Sinezoiiii Anatomidae are characterized by a slit or foramen in
diinielclreicri new species, S. iviley new species (both Scissur- the shell (lacking in Larocheidae), a rhipidoglossate rad-
ellidae), Anatoma rnpaensis new species (Anatomidae) and ula, and a lack oi nacre. Approximately 140 species are
Trogloconclw lozoueti new species (Larocheidae). One ol cin"reiitly described with an additional 90 remaining to
tire species is currently only known from the Austral Islands Ik' formalK' recognized (Geiger, 200.3; 2008). To date, no
[T. lozmic'ti). while the others seem to show a Imiad species in these families have ever been recorded from
Indo-Mala)an Archipelago to western Pacific distribution. the Austral Islands. The species described herein are all
Shells of all species and the radulae of S. danieldreieri, new to science, one witli its range restricted to the
T. lozoueti, andA.rnpacnsis are illustrated with scanning elec- Austral Islands, and three others known from several
tron micrographs. Ifjcalities in the broad Indo-Pacific.
Additional Keywords: MoUusca, Rapa Island, radula
MATERIALS AND METHODS
Standard methods for scanning electron microscopy
INTRODUCTION (SEM) were employed as detailed in Geiger (2006a,
b, c) and Geiger et al. (2007). Terminology for shell
The present contribution describes some microgas- morphology and details on method ofwhorl count have
tropods in the families Scissurellidae, Anatomidae, and been given elsewhere (Geiger, 2003; Geiger and Sasaki,
Larocheidae known from tlie Austral Islands and be- 2008). Specimens cited are diy lots; ": complete" indi-
yond. The impetus stems from a Frencfi expedition to cates wet-preserved lots with animals. All depth indica-
the southeastern-most Austral island, Rapa (see Lozouet tions refer to bottom depth.
et al. 2004; 2005 for details); for tlie species found Institutional abbreviations used in the te.vt are: BRC:
at Rapa, additional material from other localities located Bret Raines Collection, Kansas City, USA; DLG: Daniel
in \arious institutional collections has also been inclu- L. Geiger Collection, Los Angeles, USA; JTC: Jean
ded. This article is part of a series describing the bio- Trondle Collection, Paris, France; LACM: Los Angeles
diversit)^ oftliis remote archipelago (e.g., Schwabe and County Museum of Natural Histoiy, Los Angeles, USA;
Lozouet, 2006). MNHN: Museum national d'Histoire naturelle, Paris,
Scissurellidae sensu lato comprises lineages of small France; SBMNII: Santa Barbara Mu.seiuii of Natural
basal marine snails in Vetigastropoda (Geiger et al., History, Santa Barbara, USA; USNM: United States Na-
2008). The phylogenetic position ofAnatomidae is cur- tional Museum of Natural Histoiy, Washington (DC),
rently unsettled. Whereas Geiger and Thacker (2005; USA; ZMA: Zoological Museum, Amsterdam, The Neth-
unpubhshed dataj resolved a Lepetodrihis (Lepetodrili- erlands.
dae) + Scismrella, Sinezona, Sukashitrochiis (Scissurel- Other abbreviations used in text are: M: Monotyjiy;
hdae sensu stricto) clade with more distantly related OD: Original designation; SEM: Scanning electron
Anatoma (Anatomidae), Kano (2008) using the same inicroscope/microscopy/micrograph.
Page ISfi THE NAUTILUS, Vol. 122, No. 4
SYSTEMATICS high as wide towards selenizone; approximately 10 spir-
als, distinct cords near suture, diminishing to veiy fine
Scissurellidae Gray, 1847 cords near selenizone; interstices with fine irregular
Sinezona Finlay, 1926 growth lamellae. Base with constriction below seleni-
Type species: Sc]usinoj>e brevis Hedley, 1904 (OD). zone, approximately 15 elevated spiral cords, crossed
and run over by approximately 16 fine spiral lines. Um-
Remarks: The genus has recently been treated by bilicus cone-shaped, moderately wide, wall smooth, at
Marshall (2002) and Geiger (2003). distinct angle to base. Aperture D-shaped, roofoverhan-
ging. Selenizone above peripheiy, keels quite strong,
Sinezona clanicldrcieri new species moderatelyelevated, distinctlunules, elongatedforamen
(Figures 1-9)
closed anteriorly.
Description: Shell small (to 0.77 mm), trochilorm. Pro- Operculum: Thin, llexible, multispiral, with central
toconch of 1 whorl, with strong axial sculpture not
nucleus.
reaching apical suture, apertnral varLx not connected to
smootli embnonic cap, apertural margin straight. Tele- K,\i)ULA (Figures 8-9): Rachidian tooth triangular cusp
oconch I of 0.875 whorls, suture at peripheiy, approxi- with approximately live equal sized denticles. Lateral
mately 9-15 strong, raised axial cords; first spii^als after teeth 1-3 similar; outer edge ofcusp with 4-5 denticles.
0.5 whorls. Teleoconch II of 0.6 whorls, approximately Lateral tootli 4 reduced in size, hook-shaped. Lateral
four fine spiral cords at onset of selenizone between tooth 5 enlarged bv broadening, approximately six, large
selenizone and deep suture belowperipheiy, descending denticles on inner edge, 1-2 small ones on outer edge.
noticeablyon last 0.25whorls; shoulder slightlyconcave, Central denticle ol inner marginal teeth large, appro.xi-
approximateh' 1.3-20 axial cords, raised near suture, as niatcK' three denticles on inner edge, four on outer
Figure 1. HoJotype oi Sinczoiui danieldreieri new species. (SBMNFI 83540). Luniu Kect, Kliiilic Ba\, New Britain, Papiiu New
Guinea, 5.283° S, 150.131° E, 0-5 m. Scale bar, shell = 500 |iin. Scale bar, protoconch = 100 |.nn.
D. L. Geiwr. 2008 Paw ]87
edge; outer marginal teeth spooii-sliaped, hilaterallx Bohol Is, I'annlaean Island, 9.5° N, 123.917° E (AMS
S'sinmetricd with approxiiiiateK' a dozen line dentieles 406342, 1: Figure 4).
on eaeli side. Radnlar interloek moderate.
Type Locality: 0-5 m, Lunm Keel, Kinihe Bav, New
T\pe Material: Holot\pe: SBMNll 83540: Figure 1. 24 Bdtain, Papua New Guinea, 5.283° S, 150.131° E. Col.
Parat\pe.s: .3—t m. Little Santa Cruz Island. Mindanao, D. L. Geiger Oet. 2005.
6.884" N, 122.04'^' E (USNM 8124.53. 1: Figure 2).
1.5 m, Okina\\-a, Okii, Japan, 26.847° N, 128.287° El)inolog)': Tlie name honors Daniel Dreier, son of
E (LACM 77-61, 3: one illustrated Figure 3). 20 m. Off Douglas and Ilaima Dreier ofSanta Barbara, who have
Figures 2—4. ParatN-pes of Sinezona danicldreieri new species. 2. Little Santa Cruz Island, Mindanao, Philippines, 6.884° N,
122.04= E, .3-4 m (USNM 8124.53, 1). 3. Okinawa, Oku, Japan, 26.847° N, 128.287° E, 1.5 ni (LACM 77-61, 3). 4. OIT Bohol
Island, Pamilacan Island, Philippines. 9.5' N, 123.917° E, 20m (AMS 406342, 1). Scalehars, shell = 50(1 \\m. Scalebars, protoconch
= 100 nm.
Page 188 THE NAUTILUS, Vol. 122, No. 4
W
made generous contributions to the Santa Barbara Islands, 27.597° S, 144.227° (MNHN, 4: two illu-
Museum ofNatural Iliston'. strated Figures 5-6). 2-4 m, N ofAtWurapa Island, Rapa,
Austral Islands, 27.572° S, 144.350° (MNHN, 4). 2 m,
DPoilsytnreisbiuat;isohna:lloIwnrdeoe-fMeanl\a'yiarnonmAerncthsi.pelago to southern N144o.f30R3a°pWa I(tiMINsHlaNnd,, 1R)a.p2a,m,AuNstorfalAnIasWtlaaknudrs,i 2Ba7y.,62R0a°paS,,
Other Material E.xamined: French Polynesi.\: m, Austral Islands, 27.623° S, 144.307° (MNHN, 15).
Rapa ItiWIsland, Rapa, Austral Islands, 27.622° S, 3-24 m, WHiri Bay, Rapa, Austral Islands, 27.622° S,
144.302° (MNHN, 1). m, Kotuaie Point, TupuakWi 144.370° (MNHN, 4). 5 m, AnaWrua Bay, Rapa, Austral
Bay, Rapa, Austral Islands, 27.577° S, 144.343° Islands, 27.605° S, 144.378° (MNHN, 7: one
(MNHN, 1). 2 m, Nordi of Puldtarava, Rapa, Austral illustrated Figures 7, 8-9 [radula]). 6 m, Mei Point,
FUi4g2ur2eTs 5W-,7.2 mS(inMeNzHoNna).dan7.ieAlndraeriueariBanye,wRasppeac,ieAsu.st5r-a6l.IsNloarntdlsi,oFlreIn'uckhilPaoialxyan,eslilaa,pa2.7.A6u0s5t°raSl,I1s4l4a.n3ds7,8°FrVVe,n5chinP(olMynNeHsiNa,),2H7a.d59u7l°aoS,f
specimen is shown in Figures 8-9. Scale bar, shell = 500 |im. .Scale bar, protoconch = 100 |.nii.
D. L. Geiser. 200S Page 189
Figures 8-9. Radulaot Sinczoiui danicldrcicri newspecies, from specimen shown in Fi<;;nie 7. Anaiua Bav, Rapa, Anstral Islands,
27.605" S, 144.378° W, 5 m. 8. Lateral teedi 4 (L4) and 5 (L5) plus marginal teeth. 9. Hal 'i"dt"h of radula'with central field. Scale
bars =10 \\.m.
W
Rapa, Austral Islands, 27.637° S, 144.303° (MNHN, 1; Archipelago distribution, is about twice as large, has a
MXHX, 1). 6 m, SW of Gotenaonao Point, Rapa, smooth protoconch with a distinct apertural varix, and
.\ustral Islands, 27.645° S, 144.320° VV (MNHN, 3). >1 teleoconch I whorls. Sinczona globosa Geiger, 2006,
15-20 m,W\^avai, Rapa, Austral Islands, 27.590° S, from New Caledonia and Wallis Island is more rounded
144.381° (MNHN, 1; MNHN, 1). 16-20 m, MeWi in overall appearance, lacks the elevated spiral cords, is
Point, Rapa. Austral Islands, 27.637° S, 144.303° larger (3.1 mm; Geiger, 2006a), and has spiral sculpture
(MNHN, 2). 18 m, RarapaiWIsland, Rapa, Austral on the protoconch. Sinezona niacleani Geiger, 2006,
Islands, 27.572° S, 144.368° (MNHN. 1). 27 m, with broad Indo-Malayan distribution is more globular
Kauira Point, Rapa, Austral Islands, 27.592° S, 144.347° in overall outline, larger (2.3 mm; Geiger, 2006a), has a
W^ (MNHN, 1). 30 m, NW of TaunWa Island, Rapa, protoconch with flocculent sculpture, lacks the raised
Austral Islands, 27.605° S, 144.303° (MNHN, 17). ;L\ial lines and has a wider umbilicus. All the above
36 m, around Rukuaga Point, Rapa, Austral Islands, species grow to much larger size and would be imma-
27.568° S, 144.368° w"(MNHN, 8). ture with open slit at the maximum size of S. chiniel-
Philippines: Canipo Island, Cuyo Islands, Palawan drcieri.
Province, 11° N, 120.948° E (USNM 808195, 1).
Giam: 0.7 m, Ajavan Bav, S. Guam, 13.245° N, Sinezona wilci/i new species
144.717° E (LACM 77-19, 2).' (Figures 10-16)
Remarks: The protoconch sculpture shows some in- Description: Shell medium size (up to 1.08 mm) tro-
traspecific variability in die material examined. More chiform turreted. Protoconch slightly sunken in, with 1
specifically, the strong axial cords are sometimes discon- whorl, fine irregular axials, no apertural varix, apertural
tinuous. This character is not restricted to the present margin straight. Teleoconch I with 0.6-0.7 whorls, su-
species, hence, it does not seem to be ofany systematic tiu-e atperiphery, usuallywith approximately 14-22 faint
\alue. Those axial cords are also somewhat variable in to distinct fine axial cords, usually without spiral lines
widtli, die tliickenings occasionally seeming to form (occasionally faintest spiral threads only visible by SEM
some faint spiral elements. Given the intra- and inter- [Figure 11]), interstices with irregular thickenings. Tele-
specific variability ofprotoconch scidpture at this level oconch II witli up to 1.25 whorls, suture below periph-
ofdetail, the presence/absence offaint spiral elements is ei")'. Shoulder with approximately 32-44 barely
considered irrelevant for systematic purposes. Discrete perceptible to distinct fine commarginal axial cords,
differences can be observed between strong and weak stronger nearsutiu'e becoming less distinct towards sele-
axial cords as utilized previouslv in a svstematic context nizone; approximatelv eight barely perceptible to very
(Geiger 2003). indistinct spiral cords, concentrated on middle ofshoul-
Sinczona plicata (Hedley, 1899) from the Indo-Pacific der; occasional specimens with predominant spiral
has an overall wider and larger shell (2.3 mm: Geiger sculpture (Figure 11). Base distinctly constricted below
and Jansen, 2004b), more pronounced but fewer raised selenizone, axialcords ofsamestrength anddensityas on
axial cords, and a protoconch with spiral lines. Sinezona shoulder starting in lower portion of constriction below
=
ferriezi (Crosse, 1867) (? S. hoeniesi Semper, 1865: selenizone; approximately 17fine, irregularlyspaced spi-
whereabouts of Semper types unknowai. original illu- ral cords, starting in lower portion of constriction widi
stration lacking detail) with broad Indo-Malayan onset of axial lines. Umbilicus wide, walls straight.
Page 190 THE NAUTILUS, Vol. 122, No. 4
Figure 10. Holotvije of Sinezaiia icilci/i new specie.s. Lumu Reef, Kimbe Bav, New Britain, Papua New Guinea, 5.283° S,
150.1.31° E, 0-5 m, (SBMNH 8.3541). Scale bar, shell = 500 |,im. Scale bar, protoconch = 100 |.nn.
smooth, peripheiy at clfstinct angle to base, bordered by just off of Beqa Island (south of \'iti LeMi), 18.300° S,
carina. Aperture subquadratic, D-shaped, roofoverhan- 178.067° E (DLG 279, 10: one illustrated in Figure 16).
ging. Selenizone above peripheiy, keels moderately
strong, quite elevated, lunules distinctatregularinten'al; Tjipe Locality: 0-5 m, Lumu Reef, Kimbe Bav, New
foramen narrow, elongated, margins con\'erging and Britain, Papua New Guinea, 5.283° S, 150.131° E.
touching, without raphe. Animal unknown. EtMiioIogy: The name honors the collector ofthe first
Type Material: Holotype: SBMNH 83541 (Figure 10). known specimens of the species Tony Wiley of River-
35 Paratypes: 0-5 m, Lumu Reef, Kimbe Bay, New Brit- side, California, USA.
ain, Papua New Guinea, 5.283° S, 150.131° E (DLG Di.slriliiilioii: Tropical Indo-Malayan Archipelago;
639, 19: one illustrated in Figure 15). Laisse de plage shallow shelf
e.xterieure, Mururoa, Tuamotu, French Polynesia,
W
21.842° S, 138.895° (JTCW, 2: one illustrated in FigNurWe Other Material Examined: Fkench Polynesia: 36 m.
12). 20 m, Herald Pass, of Ndravuni Lsland, Around RWukuaga Bnv, Rapa, Austral Islands, 27.568° S,
end ofGreat Astrolabe Reef, Fiji, 18.767° S, 178.467° E 144.368° (MNHN, 20: Fi,gin-es II, 13). 2-4 m, N of
(HeLrAaCldMP8a5ss-,13W5, o2:f oNnderaivlulnusitrIastleadndi,n NFiWgureend14)o.f2G0rema.t WAtu(raMpNaHINsl,and1,).R5apma,.WAAunsatrmaal IBsalya,ndRs,ap2a7,.5A7u2s°trSa,l14Is4l.a3n5d0s°,
Astrolabe Reef, Fiji, 18.767° S, 178.467° E (LACM 85- 27.605° S, 144.378° (MNHN, 4). 45 Wm, Haurei Bay,
135, 2). 10-20 m. Off Francis Island in Beqa Lagoon, Rapa,AustralIslands,27.613° S, 144.305° (MNHN, 1).
D. L. Geieer. 2008 Page 191
Figures 11-13. Sincznna wilei/i new species. 11-12. Around Rukuaga Baw Rapa, Austral Islands. French PolvTiesia. 27.568°WS,
144.368= W. 36 rn (MNHN, 20). 1.3. Laisse de plage exterieure, Muraroa.' Tnamotu. French Polynesia, 21.842° S. 138.895°
:Parat\pe: JTC, 2). Scalebars, shell = 500 ^m. Scale bars, protoconeh = 100 |jm.
New C-;ledoni.^: 25-30 m, Santal Bay. Lifon, 20.822° PapuaNewGuinea: 70 ni, offSouth Enia Reef Kimbe
S, 167.173" E (MNHX, 1). .55-57 m, Koumac Sector. Bay, New Britain, 5.202° S, 150.152° E (DLG 768, 3).
20.672° S, 164.195° E (MNH\. 1). 5-25 m, Toiiho Sec-
tor. 20.878= S. 165..325= E (MNHX. 1). 8 m, Tonho Remarks: The organization of tlie foramen in this
Sector. 20.742° S, 165.265° E (MNHN, 1). species seems to be intermediaiy bet\veen the tjpical
Fiji: 10-20 m. OffFrancis Island in Beqa Lagoon,just open slit in Scissurella and tlie closed foramen in Sine-
off of Beqa Island (south of \'iti Levu), 18.300° S, zona. Altliough the margins of tlie slit are converging
178.067= E (DLG 279, 10). and fused anteriorl); a raphe is not evident. The facts
Paee 192 THE NAUTILUS. \'oI. 122, No, 4
that there is a marked downward deflection oi the last The species seems to have variable strengths ofsculp-
quarter whorl and tliat the roof of the peristome ture. Most specimens have predominant axial sculpture
attaches belo^^'the peripheiyofthe pi'eNdous whorl dem- (Figures 10, 12, 14-15), while in occasional specimens
onstrate that tliose specimens are fully grown and sliare (Figure 11) the axial sculpture is barely perceptible and
more similarities witli Sinezona tlian with SciisiircUa the spiral structures, particularly on the adumbilicalpart
with an open slit. Accordingly .S. ici!ci/i is placed in of base, become most prominent. As there are interme-
Sinezona. diate specimens (Figure 13) with distinct adumbilical
Figures 14-K>. Siuciuki uiliij, i\r\\ spicirs,paiuUpr.s, 14. Heiakl Pa.ss, \\ (il Ndravuni Island, NWendul liical A.stidlalH' Hcrl,
Fiji, 18.767° S, 178.467° E, 20 m (LACM 85-135, 2). 15. Lumu Reef, Kimlie Bay, New [Britain. Papua New Guinea, 5.283° S,
150.131° E, 0-5 m (DLG 639, 19). 16. OffFrancis Island in Beqa Lagoon,jnst olTofBeqa Island (sonth ofViti Levn). Fiji, 18.3° S,
178.067" E, 10-20 m (DLG 279, 10). Scale bars, shell = 500 ^ini. Scale bars, protoconch = 100 |.ini.
D. L. Geiger. 2008 Page 193
spiral lines and i"elati\'e!\- weak ;L\ial lines, coniliiiu'd Anatoniidae McLean, 1989
widi identic;il condition of the protoconc-h and \ei\ Aiiafoina Woodward, 18.59
small size, tiiese scnlptm'al differences arc coiisidcrcd
to constitute intraspecitic \ariabilit\. T>pe Species: .SV'/.s.svnv//*/ ciispiitd Fleming, 1828 (M).
There are no similar species in the indo-Pat'llic. Siiic-
zona feniczi (Crosse, 1867) with hroail Indo-Malayan Remarks: The genus has recently been treated by
Archipelago distribution is most similar, but is about .\hirshall (2002), Geiger (2003), and'Ceiger and Jansen
h\ice the size ofS. wileiji. has a smooth protoconch \wth (2()04a).
distinct apertin'al \arix, a teleoconch 1 with more than Anatoina rapacitsis new species
whorl, is more rounded o\'er;rll, and a distinct raphe (Figures 17-23)
anterior to the closed foramen. Siiiczona garciai Geiger,
2006, from the Caribbean, shares the protoconch sculp- Description: .Slu'll ol medium size (to 1.82 mm), tro-
ture, the absence of an apertural varix on the pioto- cliilonii biconical. Protoconchwith0.75whorls, flocculent
conch, the relati\el\' short teleoconch I with 0.6 whorls, scnjptui'e, no apertiu'al varbc, apeiiural margin slightly si-
and die narrow umbilicus. However, in addition to its nusoid. Teleoconch I with 0.3-0.4 whorls, approximate-
occurrence in a separate ocean, S. garciai has a more ly 9-12 tLxial cords, interstices with line flocculent
inflated shell with an oval aperture, which connects to sculpture, occasionall)' (holot)pe) flocculent sculpture
the previous whorl bareK' below the periphen', has onlv somewhat concentrated in position ofselenizone. Teleo-
about 0.6 teleoconch II whorls, and bears a distinct conchIIwithupto2.25whorls, sutm-eimmediatelybelow
raphe anterior to the ioramen. selenizone in early growdi, offset by width ofselenizone
Figure 17. Holot\pe of Anatoina rapaensis new species. St. 43, Haurei Bay. Rapa, Austral Islands, French PoKmesia. 27.61.3° S,
144.30.5^ \\". 4.5 ni. ('MNHX 20S23j. Scale barshell = 1 mm. Scalebarprotoconch = 100 |.un.
Page 194 THE NAUTILUS. Vol. 122. No. 4
Figures 18-20. Aiiatoiiui rapaeiisis new specie.s, parahpes (MNHN). 18-19. St. 4.3. Haiiiei Baw Rapa. .\ustral Lslands. French
Polviiesia. 27.613" S, 144.305" W,45 m (MNHN 20S24). 20. St. 48. around KukuasjaPoint, Rapa. Austral Lslands. French PoKiiesia.
27.568" .S. 144.368" W, 36 m (MNHN, 30). Scale bars, shell = 1 mm. Scale bars, protoconch = 100 ^im.
in fullygrown specimens. Shoulderconvex, approximately a\i;J and spiral cords loiining minute points. Base contin-
5.'3-66 (n = 4)axialcordsonfirstteleoconch IIwhorl,same uously slopingwith narrowumbilicus; axial cords of same
density on remaining whorls; first fine spiral cords after density and strength as on shoulder, approximately 19
0.125 whorls, approximately 7-10 after one teleoconch II spiral cords, fine spiral cords below selenizone tuniing
whorl, appro.ximately 15-22 at apertural margin (jf fully into low steps from mid-base onwards; intersection of
grown specimen, becoming less distinct and more un- spiral and a,xial cords with line points. .Aperture o\oid
evenly spaced towards apertural margin; intersections of D-sh:iped, lool oNcrJKiiigiug, l);is;il ;idunil)ilK';Ll portion