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Nine new species ofMascarene land snails(Mollusca: Gastropoda)Owen Lee Griffiths aa Bioculture (Mtius) Ltd , Senneville, Riviere desAnguilles , MauritiusPublished online: 25 Jun 2013.

To cite this article: Owen Lee Griffiths (2000) Nine new species of Mascareneland snails (Mollusca: Gastropoda), Molluscan Research, 20:2, 37-50, DOI:10.1080/13235818.2000.10673732

To link to this article: http://dx.doi.org/10.1080/13235818.2000.10673732

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Molluscan Research 20(2): 37-50 (2000)

Nine new species ofMascarene land snails (Mollusca: Gastropoda)

OWl'1I L.'/' Grillilils

Billcullure (Mlius) Ltd., S(>nnevillL-,Riviere d('s Anguilles, Mauritius

AbstractSurvey work carried out in the Mascilrene Islands of Rl;union, Mauritius ilnd Rodriguesin the S.W Indian Ocean over the last 10 years have yielded at least 14 new species, 9 ofwhich are described here:- Assimineidae: Omplllliolropis Slc1'II11(1pifchi ; Pomatiasidae:Tropidoplwm l'incl'l1fllorl'lISi; Helicarionidae: Ctl>/wplrila lli:-;rt'tlciaIll1l11; En'pla wl!l1dyslrahmi;Pacllyslyla waylll'pag('i; DlIpolllia affollclrl'lIsis; Streptaxidae: GOllospim jacobsi; GlIlellalIIa/llCIlClIsis: GlIldla argot/di.

Key words: Mascarene, land snails

IntroductionThe land snail fauna of the Mascarene Islands (Reunion, Mauritius andRodrigues) is relatively well known and consists of at least 146 species of which132 are endemic (Griffiths,1996).

However field work over the last 1() years has yielded a number of newspecies some of which are described here. These new species come from areashitherto poorly surveyed and from newly discovered subfossil deposits.

The subfossil sites include Limekiln Cave on Ill' aux Aigrettes in the southeast of Mauritius where deposits yielded shells from 53 species of non marinemolluscs (Griffiths,] 991) and those of Snail Rock in the mountains east of PortLouis (Griffiths, 1990). These deposits were dated by the amino acidracemization dating method (Goodfriend and Mitterer, 1987; Goodfriend, 1(90).The dating for snail shells from Limekiln Cave was between the end of thePleistocene and the first half of the present Holocene warm phase i.e. 15,000­5,000 years old, while shells from Snail Rock are 2,500-1,000 years old(Goodfriend, personal communication 1992). Snail shells from the othersubfossil sites on Reunion, Mauritius and Rodrigues were not dated but arebelieved by the author, on the basis of the state of the shells collected and thl'associated vertebrate remains, to date from the time of native forest clearancemost at 150 years ago.

The leaflitter samples taken were in areas of remnant middle altitude andupland forest in a number of sites on Reunion and Mauritius.

The species described are readily assignable to families occurring on theMascarene Islands and again hi~hlight the remarkable molluscan radiation onthese isolated volcanic islands.

Higher classification used herein follows Smith (1992). All type materialhas been lodged with the Australian Museum, Sydney. The SEM and normalphotos of the types were all done at the Australian Museum

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38

Systematics

O.L. Griffiths

Superfamily RISIOOIDEAFamily ASSIMINEIDAE

Subfamily OphalotropinaeTllis subfamily is confined to southeast Asia, the southwest Pacific and theislands of the lndian Ocean. In the Mascarenes it is represented by 1 genus.

O,nplJalotropis Pfeiffer, 1851This genus has the same distribution as the Subfamily. In the Mascarenes thisgenus is represented by 20 species including that described below.

On'I,I,alofropis stevanovitchi sp.n.(PIate 1, Figs. A, I)

Type triaterial:Holotype: Dead adult in leaflitter sanlple in moist upland native forest justbelow trig station at sunlmit of Piton de la Petite Riviere Noire, S.W.Mauritius,alt: 828 m, colI a.Griffiths (O.G), Jan 1992 (AMS C202885).Paratypes: three adult and subadult shells from the type locality (AMSC202863); one dead shell in leaf litter from moist native upland forest at BassinBlancf Mauritius, coll V. Florens Dec 1994 (AMS C2028(5); one worn juvenilecollected in subfossil deposits at Snail Rock 5.of Port Louis (2(;'11.4'5; 57°30.8'E).Coli. O.G June 1990. These deposits were estimated at 2,500-1,000 BP (AMSC202864). Also collected in Reunion at St Philippe; Tremblet and Takamaka,(Stevanovitch,1994). Specimens viewed before being lodged at the ParisMuseum.

Description: Shell small, conical, thin for genus, covered in thin, light hornybrown periostracum. Whorls 5, regularly increasing, convex, last whorl withvery fine keel on the periphery. Sutures moderately in1pressed. Aperture oval,except along columellar where it is almost straight Unlbilicus narro\tv. Lip thinalong lower part of the columella where it is slightly reflected outwards,otherwise unreflected. Protoconch and embryonic whorls malleated.Subsequent \vhorls covered by promineI1t, equally-spaced spiral ridges cut byirregular growth lines. Paratype from Bassin Blanc is smaller than the holotypewith slightly more angulate whorls.

Dirnensions (~f holotypc: Height: 2.26mm; Dian1eter: 1.65mm.

Anitnal: Fresh dead animal uniformly dark, operculum thin horny withmal1eated appearance.

R.enlarks: This species is readily distinguished fronl all other MascareneOnlpha[otropis by its distinctiv~ spiral sculpture and very small size. O.antelnlei,the only other 0l11plza/otropis of similar size, lacks spiral sculpture, while the onlyother 01111'halotropis with a sculpture of spiral ridges - O.I1I11ltilirata, lacks the

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Nine new Mascarene land snails 39

intersecting growth lines present on O.stevanovitchi and is 8.5mm high.Described from fresh dead specimens collected with a leaflitter sample in nativeforest.

Etymology: Named for Colette Stevanovitch who has worked on Reunion landsnails and first recorded this species on Reunion.

Superfamily LIlTORINOIDEAFamily POMATIASIDAE

This family occurs in Europe, Africa and the southwest Indian Ocean. In theMascarenes it is represented by 2 genera.

Tropidophora Troschel.1847This genus occurs in Africa and the south west Indian Ocean. In the Mascarenesthere are 14 species including that described below.

Tropidophora vincentlloret,si sp.n.(Plate 3, Figs. A, B,O.

Type material:Holotype: Subfossil adult in scree under basaltic rock overhang in degradedforest S. of eastern most peak of Trois Mamelles Mountain, Mauritius. Alt: 490m. 200 18'31''S; 57°26'43"E, coil Vincent Florens 23.5.1996 CAMS C202875).Paratypes: Five adult and subadults from the type locality, (AMS C202878).

Description: Shell depressed, planispiral, thin. Whorls 4, the first 2 raisingmarkt.>dly above the plane of the shell which is formed by the last 2 whorls. Onthe edge of the shell there are 2 prominent spiral keels, 1 forming the shoulderof the shell, the other the periphery. The first one and a half whorls areembryonic with a sculpture of irregular dendritic lines giving way to amalleated appearance. Subsequent whorls above and below have a sculpture oflow spiral ridges crossing fine radial growth lines, giving the shell a trellisedappearance under magnification. On the upper part of the shell on the last whorlthese spiral ridges number 10 between the suture and the first keel. Theunderside has a deep, wide umbilicus edged by a strong spiral ridge. The lowerspiral ridges on the underside are stronger inside the umbilicus.

Lip thin very slightly ret1ected. Shell pale horn coloured except the 2 keelswhich have an alternate dashing of brown and horn. From inside the aperturethese 2 keels appear solid brown.

DimmsiOllS of IlOlotype: Height: 7mm ; Diameter: 13mm

Remarks: Based on the shell sculpture and form, this species clearly belongs tothe genus Tropidoplwrtl. It is readily distinguished from all other MascareneTropidopllOrtl as it is the only one that is planispiral. While planispiralTropidopllOrn occur in Madagascar, all have very different sculpture and thus thisspecies is very different to the described Madagascan TropidopllOra (Fischer-

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40 o.L. Griffiths

Piette el ai, 1993). This species is only known from subfossil deposits at its typelocality. Despite considerable survey effort it has not been found, living anti isthus considered extinct.

Etyrnology: Named for its discoverer, Vincent Plarens.

Order STYLOMMATOPHORASuperfanlily HELICARIONOIDEA

Family HELICARIONIDAESubfamily Ereptinae

This subfamily is endemic to the Mascarenes and Madagascar.! where it isrepresented by nine genera.

Ctenopltila Ancey, 1882This genus occurs in Madagascar where there are two described species(Enlberton, 1994) and the Mascarenes, where there are 3 species including thatdescribed below.

Ctenoplliltt aigretteiatlu,,, sp.n.(Plate 2, Figs A, B, C).

Type I1zaterial:Holotype: Subfossil adult in limestone scree with large numbers of other snailsfrom Limekiln Cave on Ile aux Aigrettes, Grand Port, east Mauritius, coIl O.Gand Carl Jones, Feb 1989 (AMS C202886).Paratypes: 19 adult and subadult shells frOD1 the tyope locality, (AMS C202861).

Description: Shell discoidal, flat, pale glossy white. Whorls 4, regularlyincreasing. Sutures moderately impressed. Aperture oval and depressed, beingslightly below the plane of the shell. UnlbilictlS very wide. Outer lip thin, sharp,unreflected except along the lower part of the columella where it is slightlyreflected outwards. Embryonic whorls 2, smooth. Subsequent whorls \vithirregular colabral growth lines often more pronlinent above at the suture andmargin of the shell.

Dilnensions of holotype: Height: 1.55nl1n; Diameter: 2.4n1rn.

Re1narks: The only Mascarene snail that resembles this species is Ctellophilavorticella "'lith which it shares the same general shell structure and shape.However C. vorticella has very pronlinent radial ribs on both the upper andlower sides of the shell. Such ribs relnain on subfossil specimens that have losttheir periostracum. Such ribs are totally absent on C. aeg-retteianunl. This speciesis only know from the subfossil deposits at its type locality. These subfossildeposits have been dated at 15,000 - 5,000 BP. It has never been found on themainland of Mauritius and despite considerable survey effort has not beenfOllnd living on lie aux Aigrettes and is thus considered extinct.

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Nine new Mascarene land snaifs

Etyl1zology: Nanled for its type locality.

41

Erepta Albers, '1850This genus is endemic to Mauritius andl~eunion,where there are five speciesincluding that described below.

Erepta 'l1.1etldystral1ttli sp.n.(Plate 2, Figs 0, E, F)

T..1fpe 111ateria/:Holotype: Su.bfossil adult in limestone scree with large nunlbers of other snails,from LiInekiln Cave on He aux Aigrettes, Grand J'>ort/' east Mauritius, coli D.Gand Carl Jones, Feb 1989 (AMS C202877).Paratypes: 43 adult and subadult shells froln the type locality (AMS C202857);one adult subfossil shell in basalt scree under rock overhang, S edge of BassinBlanc, call V.Florens, April 1998 (AMS C202858); one adult subfossil shell inbasalt scree in lava pit, 750m SE of Bassi.n Blanc. 20°27.3'5; 57°28.5'E, coll D.G.Jan 1997 (AMS C202859); lline adult subfossiI shells in concretions on roof ofLion Mountain Cave nunlber 2, Treize Cantons, Grand Port, east Mauritius,20°22.73'5; 57°42.89'£, coil. a.G. and J.Hauchler Nov 1997 (AMS C202860).

Description: Shell depressed-conic, solid, periphery angular, pale glossy white.Whorls 5, regularly increasing. Sutures llloderately impressed. Umbilicustninutely open or completely closed by reflected columella. About 20 distinctlow, broad, irregular, radial ridges tlare out in a curved spoke-like form from theumbilicus and disappear near periphery. Outer lip thin, slightly ret1ected exceptalong colunlella where thickened and reflected outwards. Slight callosity ofcolumella near umbilicus. Embryonic whorls with fine spiral HIles. Subsequentwhorls with fine spiral Jines cut by fine, closely-spaced radial lines giving shelldecussate appearance ullder nlagnification. jJaratypes from Lion MountainCave are nlore conical than the type.

DiTnellsioHs of holotypc: l-Ieight: 4.5mnl; Dianleter: 8.5nlffi.

Rel1larks: E.I.velldystrahnli is the fifth species of Erepta in Mauritius. Of these, fouroccur in the subfossil deposits of Linlekiln Cave. E. sty/odon and E. odontina areglobose and lack the decussate sculpture of E. (L?cndystrahnli. E. sefiliris, althoughsilniJar ill shape to E. 'll'clldystaJzl1li, has a broad, deeply excavated umbilicus. E.thirouxi the only Erepta not found in Linlekiln Cave is conical and also lacks adecussate scull-,ture. In addition to the above differences, E. zoelldysfalzTlli is theonly Erepta with the distinctive broad spoke-like ridges on Ule underside of tileshell. Erepta ll)clldyslrall1l1i is only knoWll from subfossil deposits. Despiteconsiderable survey effort has not been found living on Mauritius or lIe atlX

Aigrettes and is thus considercli extinct.

Efytnology: Nanled for Wendy Strahm \'",ho was responsibll' for theestablishment uf lie aux Aigrettes as a properly managed nature reserve.

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42 O.L. Griffiths

Pacl,ystyla Moreh,1852This genus is endemic to ReWlion and Mauritius where there are 3 speciesincluding that described below.

Pac1lystyla 'lvaynepagei sp.n.(Plate 3, Figs. Df E, F).

Type 11laterial:Holotype: Subfossil adult, unique specimen, in limestone scree with largenumbers of other snails, from Limekiln Cave on lIe aux Aigrettes, Grand Port,east Mauritius, coll Wayne I>agc, June 1996 (AMS C 202871).

Description: Shell large, solid, globose with rounded periphery, \vhite on upperwhorls, last whorl orange to hom with 5 mm wide white band just aboveperiphery. Whorls 7, regularly increasing. The suture is not impressed in the first4 whorls and is slightly margined. In subsequent whorls the suture is deeplyimpressed as a result of damage whicll was repaired by the snail at that point.Unlbilicus closed, columela broad with slight excavation down nliddle. Lip thinnot reflected. Shell smooth with faint growth striae visible under highmagnificatioll.

Dbnensio11S of holotype: Height 28mnl; Diameter 39mm.

Remarks: The deposits at Limekiln Cave yiellied only one specimen of P.waynepagei and many specimens of Pachystyla bicolor. All P. bic%r were verylarge (max dialn: 48mm) with a very sharp keel. All retained evidence of thedecussate sculpture that is a feature of the species. All \vere either bleachedwhite or retained their conlplete brown colour. P. waynepagei by contrastcompletely lacks these features. Even allowing for the effect of the injury, thetype's form is very distinct. The orange last whorl with its peripheral white bandis also a feature absent on P. bie%r. P. loaytlepagei has never been found on thenlainland of Mauritius and despite considerable survey effort has not beenfound living on lIe aux Aigrettes and is thus considered extinct.

Etynlology: Nanled for Waylle Page of the Mauritian Wildlife FOllndation whodiscovered the unique specimen of this species.

Dllpolltia God\vin-Austen, 1908This genus is endemic to Madagascar and the Mascarenes. In the Mascarenesthere are 8 species, including that described below.

Dupollfia affollchetlsis sp.n.(Plate 3, Figs. G, H, I)

Type 111aterial:Holotype: Subfossil adult shell, in limestone scree with tortoise and solitairebones, below day-light hole, Caverne L'Affouche, just east of Anse Quittor

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Nine new Mascarene land snails 43

Reserve, Plaine Corail, Rodrigtles. 19°45.40'5; 63°22.12'E, coil ex; and Carl Jones,Dec 1997 (AMS C202887).Paratypes: one adult shell from the type locality (AMS C202872); one adult shellin limestone scree, Caveme Palate, Plaine eOTail, Rodrigues, colI OG and CarlJones June 1989 (AMS C 202873); 18 adult and subadult shells; in limestone screebelow day-light hole, Caverne Bambara no 3, just east of Anse Quittor Reserve,Plaine Corail, Rodrigues. 19u45.36'S; 63n22'E, colI OG and Carl Jones, Dec 1997(AMS C 202874 ).

Description: Shell depressed, thin, periphery rounded, pale glossy white with athin brown band bordering the suture and continuing on the last whorl justabove the periphery. Whorls 4, regularly increasing. Sutures distinctly marginedUmbilicus narrow, partially closed by reflected upper part of the culumella.Outer lip thin, sharp with no peristome. Aperture broader than high, lunatedescending slightly below tIle plane of the shell. Shell appears smooth with finespiral lines apparent under high magnification. In nlany specimens tIle brownbatld is absent.

Dimensions of holotype: Height: 5.5mm; Dianleter: 11 mm.

Remarks: This species has only ever been found in the limestone (Calcarinite)deposits of the South West of Rodrigues, an area of palm savannah that wascompletely burnt over and cleared in the 1830's. While there is an extensiveradiation of Dupontia on Mauritius and Reunion, this is the only knownDUP011tia from Rodrigues. It differs from all other Mascarene Dupontia by it'sslightly larger size, Olore globose shape and glossy white colour. It is also theonly described Dupollfia with a peripheral band. Despite considerable surveyeffort has not been found living on Rodrigues and is thus considered extinct.

Etymology: Named for its type locality.

Superfamily STREPTAXOIDEAFamily STREPTAXIDAE

This family is widely distributed tllroughout the tropical and subtropicalregions of the world. In the Mascarenes there are 6 genera. TI,e extensiveradiation of Streptaxidae in the Mascarenes is one of the features of the fauna,witll at least 39 species already described (Griffiths,1996). While Madge (1938)considered that Gonospira is "already overcrowded with numerous verypolymorphic species", the species described here are very distinct and cannot beassigned to allY existing species.

Gonospira Swainson, 1840This genus is endemic to the Mascarenes, \vhere it is represented by 32 speciesincluding that described below.

Subgenus Microstrophia Mollendorff, 1887Gonospira (Microstropllia) jacobsi sp.n.

(Plate 1, Figs. H, K)

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44 D.L. Griffiths

Type material.'Holotype: Live colJected adult, in dried leaflitter sample collected at base of treein degraded moist upland native forest just below the summit on the easternside of Mt Brise Fer, W. Mauritius at 622 TIl, coli O.G and Vincent Florens June1994 (AMS C202883).Paratypes: three adult alld eight subadult or juvenile shells collected at the typelocality (AMS C202866); one adult and one subadult subfossil shell/ under deeprock piles belo\\r the scarp on the northern side of Snail Rock, south of Port LouisMauritius, 20°11.4'5; 57°30.8'E, call by O.G, June 1990 ( AMS C 202867 ), snailsfrom this site have been dated at 2,..,00 -1,000 BP; one old dead adult shell, underrock at base of scarp, SW side of Le Mome, SW Mauritius, call O.G May 1991(AMS C 202868); one adult subfossil shell, under rock pile, Mt Brise Fer, coIlVincent Aorens, 1997 (AMS C 202869).

Description: Shell cylindrical, but slightly broader near apex, spire flattened,translucent horn to white. Aperture elongate, set to one side and projecting tube­like away from plane of shell. Lip thickened, well reflected. Upper tllird ofaperture nearly separated by strong protruding parietal lanlina which almosttouches thickening within peristolne on right side of aperture. Umbilicus verynarrow, slit-like in adults, extremely broad in juveniles. Whorls 7, regularlyincreasing. Embryonic whorl \vith a nlalleated appearance. Subsequent whorlscovered \-vith regular, prominent, backward reflected" growth ridges. Thesubfossil paratype from Mt Brise Fer is very elongate: Height: 4 nlm and has 9whorls.

Di111C11Sio11S of Izolotype: Height: 2.8 mm; Diameter: 1.4 mm. Aperture height: 0.9mm; width: 0.5 mnl.

Anhllal: Unrecorded.

Renlarks: While there are six Mascarene streptaxids less than 4mm in length noneof them have the flattened spire and cylindrical shape, together \'\lith the boldgrowth ridges, that characterise this species. The species is assigned to thesubgenus Microslrophitl because of its very widely unlbilicate discoidal juvenilestage. Juveniles with their broad umbilicus and discoid shape appear at firstglance to be very different to adults. GOl1ospira s.s. in conlparison, have a verynarrow unlbilicus in the juvenile and adult stage. The 3 other species of thesubgenus Microstrophia are also figured for conlparison. (Plate 1, Figs E, F,G ).This snail has been found living only at one small site on the summit of Mt BriseFer, which is also the only place where the large endt'mic helicarionid ErepfasfylodolI still lives. Given its extremely limited range this species nlust beconsidered (following the IUCN classification) as threatened. Its OCCllrrence insubfossil deposits at Snail Rock in the N.W and at Le Morne in the SW ofMauritius indicates it previously l1ad a much broader range.

Et-yI110Iogy: Named for Jacob Griffiths, the eldest son of its discoverer.

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Nine new Mascarene land snails 45

GlIlella Pfeiffer, 1856"fhis genus occurs in Africa and the south \-vest Indian Ocean. ]n the Mascarenesthere are two species already described as well as G.l1ltll11Cllcnsis and (;.arxoudidescribed below.

ellielfa ",al1lellellsis sp.n.(l)late I, Figs. B, C)

Type fnaterial:

Holotype: Stlbfossil adult shell in scree under basaltic rock overhang indegraded forest at base of northern scarp of Trois Mamelles Mountain, colIVincent Flarens 2.1.199.5 (t-\MS C202884).Paratypes: four adult and subadult shells from tIle type locality (AMS C202870).

Description: Shell cylindrical, 7 \vhorls, with shell 'Alidest at level of third andforth whorls. Protoconch with faint malleations, rest of shell smooth. Apertllreelongate, set to one side and projecting tube-like a\\l'ay from plane of shell. Lipthickened, retlected, projecting further fron1 aperture along colun1cla and base.Much of aperttlre filled by Olle strong protrllding parietallalnina which extendsfrom deep inside aperture to beyond plane of lip. Parietal lamina curves alongnlost of its length towards outer lip, which it nearly joins at point of a stronglabral thickening within peristome on lower right. Subadults finely perforate.

Dil1LCnsiolls of the holotype: I-Ieight 2.6mm; diall1eter:1.3mm

Retnarks: The form of the aperture suggests that it might be placed in GOllospira(Microstrophia). I-Iowever the absence of a broadly umbilicate juvenile stage, thesnlooth shell and nature of the apertural lamina and thickening place it in thegenus Gulella, It differs frolll G. anl'elnzcana (the only Mascarene Gulella withwhich it could be confused) which has a broad rounded aperture and a simplesmall parietal lamina. Despite considerable survey effort this species has notbeen found else\\'here and must be considered extinct.

EtynlolvgtJ: Nan1ed for its type locality.

eulella argoudi sp.n.(Plate 1, Figs. 0, J)

Type luateril1l:J-Iolotype: Subfossil adult shell, buried 10 enl deep in dry soil under basaltic rockoverhang on edge of ravine cutting the old part of Chemin Bnlniquel, E. of LaSaHne Les Bains, Reunion, at 250 n1. 21°4.8'5; 55°15.8'E, coil ().G., C.Stevanovitchand J.J.Argoud, Dec 1992 (AMS C202876).Paratypes: One adult and one subadult shell from the type locality, (AMSC202862).

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46 D.L. Griffiths

Description: Shell cylindrical, 5 whorls, with conical apex. Protoconch faultlymaleated. Rest of shell with strong closely spaced, wavy, slightly obliquecostulae. Aperh.lre rounded at base. Lip thickened, well reflected. Upper part ofaperture with a thickened short parietal lanlina, alnlost llleeting a blunt labraldenticle about half way dOWll Iabrunl, which corresponds to a s111all external pit.Upper part of colunlellar has snlall flat process inside aperture. Unlbilicus slit­like in adults, rounded and faintly perforate in juveniles.

Dinlellsions of holotype: Height: 3.7nlnl; Diameter: 1.8rnnl.

Relnarks: The strong costulate sculpture con1bined with the distinctive aperturaldentition seperates this readily from all other Mascarene streptaxids. I-Ioweverthe features of the shell are cllaracteristic of the Gulella ill.~111S group of SouthernAfrica (Dr van Bnlggen pers comm 1995). According to Dr van Bruggen 1/ in thecase of Reunion, occurrence of a species of the Gil/ella in[tzJls group widelydistributed in southern Africa is at least renlote thus we Blight surmise a sharedancestry of both species". G.argolldi is distinguished from the South Africanmenlbers of the G.infnns group by its slnaller size- 3.7m!11 vs 4.8-6.71nm high fornlembers of the G.illfalls group (fronl Connolly,M.,1939). The "'harls of G.argoudiare also more rounded. This species is thus readily distinguished from G.infal1s.G.l1rgoudi fornls a conlpletely new element in the Mascarene streptaxid faunaand represents a separate, n1uch more recent and llnradiated invasion.Although described from subfossil specinlens, the presence of a Gulella shellfragment (possibly belonging to this species) collected in leatlitter at Cap Noire,Dos-d'Ane Reunion, at 1300m.. in 1992, suggests this species may still survive.

EtY11101ogy: Nanled for its co-discoverer, Jean-Jaques Argoud of ReWlion.

AcknowledgementsI anl nlost grateful to the following ~"leople for their assistance: Vincent FIorensand Carl Jones of Mauritius, Jean-Jacques Argoud of Reunion Wendy StrahlTI ofSwitzerland, Colette Stevanovitch of France and Wayne Page of England, all ofwhom helped me collect material; Dr Winston Ponder, Phil Coleman and IanLock of the Australian Museum and Fred Naggs of the British Museunl whomade helpful comnlents on the l1lanuscript; Stephanie Clarke and Alison Millerof the Australian MuseUlll who prepared the SEM photos and plates and GlennGoodfriend of the USA "vho dclteli subfossil nlaterial.

ReferencesConnolly, M. '1~3Y. A Inonographic survey of South ;\frican non-nlarine n,ollusca. A"l1a/~

of tile South ;\frictlll MliSelllll. 33(1): 669pp.Enlberton, K.C. 1994. Thirty ne\·v species of Madagascan land snails (Mollusca:

Gastropoda). Proct!cdinSs (~l tire Actldtll11Y or l\JallJl"tll SCiel1(~s or Phi/adelphia 145:147-18Q.

Fisher-Piette, E., Blanc, Ch.P, Blanc, F., Salvat, F. 19C)3. Gasteropodes TerrcstresProsobranches. in FaUl1C de Madagascar 80. Museunl National d'Histoirl'Narurelle Paris. 281 pp.

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Nine new Mascarene land snails 47

Goodfriend, G.A., Mitterer, RM. 1987. Late Quaternary Land Snails from the North Coastof Jamaica: Local extinctions and climatic charge. Palaeogeography,Palaeoclimatology, Palaeoecology, 63: 293-311

Goodfriend, G.A. 1990. Patterns of racemization and epimerisation of amino acids in landsnail shells over the course of the Holocene. Geochimica et Cosmochimica Acta55: 293-302.

Griffiths, O.L 1990 Landsnails of Le Pouce Mountain, Mauritius. The Papustyla Manustlllld Snail Society 10/90: 2-3.

Griffiths, O.L. 1991. Landsnails from a Mauritian limestone cave. The PapListyla ManusLand Snail Society 1/91: 12-15.

Griffiths, o.L., Cook, A. & Wells, S.M. 1993. The diet of the introduced carnivorous snailEuglandina Tosea in Mauritius and its implications for threatened islandgastropod faunas. Journal of Zoology, London 229: 79-89.

Griffiths,O.L. 1994. A review of the land snails of Rodrigues Island (Indian Ocean) withnotes on their status. Journal of Conchology, London 35(2): 157-166.

Griffiths, O.L. 1996. Summary of the land snails of the Mascarene Islands with notes ontheir status. Proceedings of the Royal Society of Arts and Sciences of Mauritius VI:37-48.

Madge, E.H. 1938. Notes on some non-marine Mollusca of Mauritius with descriptions offour new species. Mauritius Institute Bulletin 1(3): 15-29.

Smith, B.J. 1992. Non-Marine Mollusca. In Houston, WWK (ed) Zoological Catalogue ofAustralia. Canberra: AGPS 8 (xii). 405pp.

Stevanovitch, C. 1994. Protection des Mollusques terrestres endemiques de la Reunion.Rapport d'etude commande par Ie Ministere de L'Environnement

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48 c.L. Griffiths

Plate 1.A. Omphalotropis stevarzovitchi sp. n. Holotype. B.Gulella n1an1ellel1sis sp.n. Holotype.c. Gll/ella 1nanzcllensis sp.n. Holotype. o. GuleLla argoudi sp.n. !-Iolotype. E. Gonospira(Microstrophia) clavulata (AMS C202880) Piton de la Petite Riviere Noire. E Gonospira(Microstrophia) rnodesta (AMS C202881) Piton de la Petite Riviere Noire. G. Gonospira(Microstrophia) nana (AMS C202882) Nouvelle France, Mauritius. H. Gonospira(Microstrophia) jacobsi sp.n. I-Iolotype. I. OmphaLotropis stt!vanovitchi sp.n. protoconch.Holotype. J. Gulclla argoudi sp.n. protoconch. Holotype. K. GOl1ospira (Microstrophia)jacobsi sp.n. protoconch. Holotype.Seal€.' Bars: A, B, C, 0, G, H: Imm; E, F: 2mn1; I: 200f.lm; J, K: 500J.lm

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Nine new Mascarene land snails 49

Plate 2

A, B, C. Ctenophila aigretteianum sp.n Holotype. 0, E, F. Erepta wendystrahmi sp.n.Holotype.Scale Bars: A, B, C: lmm; 0, E, F: 2mm

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50 O.L. Griffiths

Plate 3A,B, C. Tropidophora l1illcelltflorrnsi sp.n. Holotype. 0, E, F. Pachystyla wayllepagci sp. n.Holotype. G, H, I. DUpoiltia affouchcllsis sp.n. Holotype.Scale Bars: A,G: 5.3mm; 0: 8.9mm

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