Trochomorpha thelecoryphe Vermeulen, Liew & Schilthuizen

Vermeulen, Jaap J., Liew, Thor-Seng & Schilthuizen, Menno, 2015, Additions to the knowledge of the land snails of Sabah (Malaysia, Borneo), including 48 new species, ZooKeys 531, pp. 1-139 : 98-100

Taxon classification Animalia Stylommatophora Trochomorphidae

Trochomorpha thelecoryphe Vermeulen, Liew & Schilthuizen sp. n. Figure 81

Holotype.

Malaysia, Sabah, West Coast Province, Kinabalu N.P., near Summit trail (leg. T.S. Liew et al., BOR/MOL 6047).

Examined material from Sabah.

West Coast Province. Kinabalu N.P., Kotal’s route between 1992 and 2280 m (leg. T.S. Liew, J. Lapidin, Safrie & Jasilin, BOR/ MOL 4395, BOR/MOL 4398); Mesilau trail between 2120-2288 m (leg. T.S. Liew, BOR/MOL 4402, BOR/MOL 4397; leg. T.S. Liew & J. Lapidin, BOR/MOL 4394, BOR/MOL 4234).

Description.

Shell rather small, rather thin, about opaque, yellowish brown, low-conical with somewhat convex sides; apex protruding. Surface with a silky luster above the periphery, shiny below. Whorls: Apical whorls convex, outer slightly convex; suture hardly impressed, coinciding with the periphery; last whorl acutely angular and compressed at the periphery, rounded below the periphery. Protoconch c. 1 7/8 whorls, with dense radial riblets except at the apex, and a spiral striation cutting into the radial riblets towards the teleoconch; transition to teleoconch sculpture gradual. Teleoconch. Radial sculpture: above the periphery rather densely placed, more or less regularly spaced riblets; below the periphery growth lines only. Spiral sculpture: last whorl with a peripheral thread; start of fifth whorl with c. 13 spiral threads: c. 10 rather distinct, rather low and wide threads but with a narrow crest, which are highest, or form nodes over the radial sculpture, and c. 3 similar but less conspicuous threads interspersed; no spiral sculpture below the periphery. Umbilicus closed. Peristome (not present on the material available). Dimensions: Height c. 6 mm; width c. 11 mm; h/w 0.54-0.55; diameters of the first 4 whorls c. 1.7 mm, c. 2.8 mm, c. 5 mm, c. 8 mm respectively; number of whorls c. 5 1/8, height aperture c. 3.5 mm; width aperture c. 6 mm.

Habitat in Sabah and distribution.

Montane forest on sandstone bedrock, 1900-2300 m alt. Sabah: Mount Kinabalu only. Endemic to Sabah.

Cross diagnosis.

Similar to Trochomorpha haptoderma in coiling density and sculpture; differs by having a flatter spire, with a more protruding apex.

Remarks.

The only available shell is a juvenile with the last 1/8 whorl broken. The description needs to be amended once more material becomes available.

Etymology.

The name refers to the protruding apex [thele (Gr.) = nipple; coruphe (Gr.) = summit].