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https://doi.org/10.24199/j.mmv.1972.33.13 7 February 1972 TASMANIAN SNAIL REFERRED TO THE GENUS VICTAPHANTA (STYLOMMATOPHORA: PARYPHANTIDAE) By Brian J. Smith Curator of Invertebrates, National Museum of Victoria, and R. C. Kershaw Honorary Associate, Queen Victoria Museum, Launceston, Tasmania Abstract The genus Melavitrina Iredale (1933) is placed in the synonymy of Victaphanta Iredale (1933) and the distribution of the three species of Victaphanta is discussed. The anatomy of the Tasmanian species Victaphanta milligani (Pfeiffer 1853) is described. Introduction mouth' and the surface is shining black. How- ever, the slight enlargement of the last whorl Following recent work on the Victorian compared to the two Victorian Victaphanta paryphantid genus Victaphanta Iredale 1933 species is here considered of specific signifi- (Smith 1969, 1970), the closely similar group cance. The shell being thin, composed mainly of snails from W. Tasmania belonging to the of conchin with very little calcareous material, genus Melavitrina Iredale 1933 were consider- umbilicus nearly closed, glossy with the inner ed. Two species are described for the genus, whorls white to yellow and outer whorl dark M. milligani Pfeiffer (1854) and M. jumosa brown, are all features of the genus Victa- Tenison-Woods (1878) and these have often phanta. been closely compared to the Victaphanta species (Tenison-Woods 1878, Murdoch 1904, With the inclusion of the Tasmanian species Cox and Hedley Davies Iredale's 1911, 1912). in Victaphanta, the number of species increases (1933) description of Melavitrina was not to three and gives a circum-Bass Strait distri- considered sufficient to separate these species bution for the genus (PI. 9, fig. 7). This is from Victaphanta and Tenison-Wood's descrip- further reinforced by the discovery of sub- tion of M. jumosa was not considered sufficient fossil shells very similar to V. milligani in the to separate this species from M. milligani. The dunes of Flinders Island giving a date for the object of this paper is to establish Victaphanta existence of this fauna of up to at least 6,000 milligani as the single Tasmanian species of this years ago (E. D. Gill pers. comm.). All three genus, and to relegate Melavitrina and jumosa species are confined to the wet temperate rain- to the synonymy of these taxa. forest areas. Generic Placement Victaphanta milligani (Pfeiffer, 1853) The genus Victaphanta was redescribed by (PI. 9, figs. 1-6) Smith (1969). Both Iredale's scant description Vitrina milligani Pfeiffer, 1853, Monographia Heli- of the genus Melavitrina, and the shell and ceorum Viventinm, Lipsiae 3: 4 other anatomical features of the type species Vitrina milligani PfeilTer, 1954, Proc. zool. Soc. Lond. 20 (1852): 56 M. milligani fall within that description. Ire- Helicarion milligani Gray, 1855, Cat. Br. Mus. nat. dale (1933) differentiates the genus from Hist., Pulmonata 1: 68 Helicarion Ferussac and Paryphanta Albers Vitrina milligani Pfeiffer, 1856, Malakozoologische because the last whorl is large with an 'open Blatter, Cassel, 2: 116 111 112 B. J. SMITH AND R. C. KERSHAW Vitrina milligani Shuttleworth, 1856, Notitiae Mala- Distribution The animal appears to be cologicae, Leipzig, 1: 16 confined to the W. or N.W. portion of Tas- Paryphanta milligani Albers, 1861, Die Heliceen. mania but the lack Leipzig, p. 48 of comprehensive collecting makes a precise statement of locality impos- Vitrina milligani Reeve, 1862, Conch. Icon. 13, Vitrina sp. 18 sible. Specimens are in museum collections Vitrina milligani Cox, 1868, Monograph of Australi- from the forest areas of the Duck River, an Land Shells, Sydney, p. 82, pi. 14, figs. 2-2a Montague River and Arthur River of the N.W. Helicarion fumosa Tenison-Woods, 1878, Proc. Linn. corner of Tasmania, and from a wide area to Soc. N.S.W. 3: 124, pi. 12, figs. 3-3a the N. and E. of Strahan and Queenstown. In Helicarion milligani Tryon, 1885, Man. Conch. (2) this 1: 172, pi. 26, figs. 11-12 latter area specimens were collected from Paryphanta fumosa Murdoch, 1904, Trans Proc Mt. Zeehan, Mt. Farrell, Mt. Pelion as well as N.Z. Inst. 36: 156, pi. 6 around Queenstown and Macquarie Harbour. Paryphanta milligani Petterd and Hedley, 1909, Rec. They also presumably occur at localities be- A list. Mas. 7 (4): 287 tween these two areas but more collecting is Paryphanta fumosa Petterd and Hedley, 1909, Ibid., needed. Specimens have also p. 287 been reported (A. J. Dartnall pers. comm.) from the Port Paryphanta milligani May, 1921, Check-list of the Mollusca of Tasmania, p. 92. Davey area of S.W. Tasmania so the species Paryphanta milligani var. fumosa May. 1921. Ibid may occur in all the wet forest areas of the p. 92 W. half of that State. Melavitrina milligani Iredale, 1933, Rec. Aust Mus 19 (1): 40 Anatomical Notes Four specimens were Melavitrina milligani Iredale, 1938, Aust. Zool 9 used in this study, two collected from near (2): 116 Montague River by R. C. Kershaw, one Aus- Melavitrina fumosa Iredale, 1938, Ibid., p. 116 tralian Museum specimen collected near Zee- Melavitrina milligani Macpherson, 1958, Illustrated han, and one from J. Index A. Dartnall, collected of Tasmanian Shells, p. 46, pi. 42, fig. 13 between Queenstown and Zeehan. The anatomy Diagnosis Paryphantid snail, shell depress- of M. fumosa has been described by Murdoch edly globose, thin, composed mainly of con- (1904) and both his findings and the present chin, glossy, inner whorls white to yellow to study show the anatomy to be very similar to dark blown, spire nearly flat, suture deeply that described for the other two species of impressed, last whorl wide, aperture large, Victaphanta (Smith 1970). It was therefore oblique, umbilicus almost closed, fine concen- considered necessary to describe only those tric fines on upper surface, lower surface aspects of the anatomy which differ from those almost smooth. Animal black with orange foot described for V. atramentaria and V. compacta. and mantle edge. Pharynx long, cylindrical, Pallial Region This region is similar to radula spatulate, without rachidian, teeth that of the other species, with the lappets aculeate, unicuspid, approximate formula around the pulmonary orifice, the termination 38-0-38 to 41-0-41, of 78-86 rows. Repro- of the rectum in a deep groove just posterior ductive system simple, vas deferens free from to the orifice, and the pseudoureter running common duct, attached to outer wall of vagina, along side of the rectum. The kidney appears running in a loop past genital atrium and larger than in V. atramentaria and there is no entering penis at posterior end, penis longer sign of the mantle than vagina. gland on the posterior margin of the collar as suggested for that Type Material Lectotype, here designated, species by Smith (1970). and two paralectotypes in the British Museum Alimentary System The only difference (Natural History) No. 1969265 collected from in the alimentary system between this species a small island in Macquarie Harbour, Tas- and the two Victorian species is in the radula. mania Cprobably by a Mr. Milligan). Dimen- The radula is spatulate, without a rachidian sions of lectotype (from photograph), max. and the teeth are aculeate, unicuspid with diam. 21.9 mm, min. diam. 15.8 mm. oblong base plates. The teeth formula is TASMANIAN SNAIL SPECIES 113 38-0-38 to 41-0-41 x 78 to 86 rows. The teeth expected the description to appear in the issue increase in size from the margins to a maxi- prior to the publication of the third volume mum about four teeth from the centre, and of his Monographia. The descriptions in both then decrease sharply. This compares with references are identical, but this priority should teeth formula of 64-0-64 to 67-0-67 x 102-105 be borne in mind when dealing with other rows for V. atramentaria and 60-0-60 to species described in these papers. 63-0-63 x 99-103 rows for V. compacta. H. jumosa Teni son-Woods 1878 is here The pharynx is very large and muscular, reduced to the synonymy of V. milligani as the filling the head-foot cavity. The oesophagus minute differences used to separate it from arises as a narrow tube from the dorsal surface milligani fall within the intraspecific variation of the pharynx about a third of the along way of that species. One of us (RCK) has collected its length. The salivary glands are fused into a series of specimens from the one locality on a single almost ovoid body, although its origin the Montague River which show all stages of as two separate bodies can be seen by the variation between the two 'forms'. lobing. Victaphanta milligani differs from the two Reproductive System This system differs Victorian species of the genus in the size and from that of the other two Victaphanta species shape of the shell, the number of teeth per in three respects (PI. 9, fig. 6). 1. The common row in the radula, and the structure of the duct is similar but the prostate gland is mainly reproductive system. The shell is smaller confined to the anterior end of the duct with (maximum diameter approximately 24 mm), only a small amount at the posterior? end. 2. and characterised by its brown colour, the In the Tasmanian species the spermathecal extreme enlargement of the last whorl, and the duct is short. The simple sac-like spermatheca wide oblique aperture approaching that of a is situated in a fold of the anterior end of the vkrinid. The radula averages only 38-41 teeth common duct immediately posterior to a point per half row compared to 60-63 for V. com- where the vas deferens emerges from the com- pacta and 64-67 for V.