Elatonitor montanus Stanisic, 2010

Hyman, Isabel T. & Köhler, Frank, 2022, Homoplasy in shells discombobulated the taxonomy: revision of the larger helicarionid land snails of northern Queensland, Australia (Stylommatophora: Helicarionidae), Journal of Natural History 56 (41 - 44), pp. 1727-1799 : 1791-1792

Elatonitor montanus Stanisic, 2010

( Figures 4 , 22 (a), 23)

Elatonitor montana [sic!] Stanisic, 2010: 298–299.

Material examined

Holotype. QM MO48601 , Bellenden Ker Range , summit TV Stn, north-eastern Qld, Australia (17°03ʹS, 145°42ʹE), rainforest, 1560 m, 29 April 1983, G. Monteith, D. Yeates.

Paratypes. QM MO11240 , QM MO48363 , QM MO48374 , QM MO78930 .

Diagnosis

External morphology. Shell ( Figure 22 (a)) medium-sized (SW 13.9–18 mm), amber, often darker below periphery, 5.3–5.7 whorls, trochoidal with a moderate spire, whorl profile strongly angulate; microsculpture of very fine spirals on protoconch and teleoconch; umbilicus very narrow. Body light brown with cream-coloured lappets (in alcohol). Mantle lobes small; shell lappets long, narrow, tapering. Caudal horn moderately large.

Genital anatomy. Genitalia ( Figure 23 ) with moderately long vagina, internally with longitudinal ridges; bursa copulatrix moderately short, duct narrow, internally with longitudinal ridges; bursa elongate. Penis moderately small, tubular; internally with three longitudinal pilasters, two of them merging basally, internal wall sculptured with longitudinal wrinkles; penis and part of epiphallus enclosed in penial tunica. Epiphallus enters penis through a simple pore; epiphallus longer than penis; epiphallus 2 longer than epiphallus 1; epiphallic caecum absent; flagellum long, slender, without obvious internal cryptae, last third slightly swollen.

Remarks

Elatonitor montanus is known only from montane rainforest on Mt Bellenden Ker and Mt Bartle Frere, above 1200 m elevation. The only material available in the current study was from Mt Bellenden Ker ( Figure 4 ). A close comparison with specimens from Mt Bartle Frere would be of benefit, as these populations are isolated from one another and it is possible that the Mt Bartle Frere population represents a separate species.

This species can be distinguished from its congener E. suturalis by its slightly smaller size and trochoidal shape; it can be distinguished from all other large helicarionid snails of northern Australia by its sharply angulate whorls.

Figures

Figure 4. Distribution map. Grey symbols: Geminitor. Blue symbols: Pravonitor. Red symbols: Elatonitor. Biogeographic barriers are marked in black; A = Normanby Basin, B = Black Mountain Corridor, and C = Atherton Tableland.

Figure 22. Shells of Elatonitor. a) Elatonitor montanus, QM MO48601 (holotype). b) Elatonitor suturalis, NHRM 940 (paralectotype). Scale bar: 10 mm.

Figure 23. Genitalia of Elatonitor montanus. a) QM MO38930, Bellenden Ker Range. Reproductive system. b) QM MO78930, Bellenden Ker Range. Penis interior. c) QM MO11240, Bellenden Ker summit. Penis interior. Scale bars: 1 mm.