Kaliella eurytrochus 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 : 69-70

Taxon classification Animalia Stylommatophora Euconulidae

Kaliella eurytrochus Vermeulen, Liew & Schilthuizen sp. n. Figure 60

Holotype. Malaysia, Sabah, Interior Province , Gunung Trusmadi slopes , Gua Loloposon ( RMNH.5003922 ).

Examined material from Sabah.

Interior Province. Gunung Trusmadi slopes, Gua Loloposon (leg. J.J. Vermeulen, V 13237). Tawau Province. Danum Valley Conservation Area, 2 km N.W. of Danum Valley Field Centre (leg. H.A. Rutjes, V 13513).

Description.

Shell small, rather thin, somewhat translucent or opaque, pale yellow-corneous to white, depressed-conical with approx. flat or slightly convex sides; apex rounded. Surface shiny. Whorls moderately convex, last whorl angular at the periphery, rounded above and below the periphery. Protoconch whorls convex, with numerous fine, rather densely placed radial riblets, which are most distinct below the suture; numerous approx. equally strong, densely placed spiral grooves cutting into the crests of the radial riblets. Teleoconch: Last whorl with a peripheral spiral thread coinciding with the suture of the penultimate whorl, above and below this numerous fine, moderately and regularly spaced, continuous spiral grooves. Radial sculpture: growth lines above the periphery, at somewhat irregular intervals, which are approx. as strong as the spiral sculpture, and which are most distinct just below the suture. Umbilicus closed. Dimensions: Height up to 2.65 mm; width up to 3.8 mm; diameters of the first four whorls 0.80-0.85 mm, 1.5-1.6 mm, 2.35-2.50 mm, 3.6-3.7 mm respectively; number of whorls up to 4 1/8; height aperture up to 1.5 mm; width aperture up to 2.0 mm.

Habitat in Sabah and distribution.

Primary forest on limestone and sandstone soil. Alt. c. 400-1000 m. Sabah: Gunung Trusmadi; Danum Valley. Two localities. Endemic to Sabah.

Cross diagnosis.

Differs from Kaliella gregaria by its smaller size, at the same number of whorls. In Kaliella eurytrochus , the whorls increase less fast in width; compare the diameters of the third whorl of both species. The shell of Kaliella eurytrochus is also distinctly thicker, and less fragile.

Etymology.

The name refers to the inflated shell shape [eurus (Gr.) = wide; trokhos (Gr.) = wheel, a word often used for the gastropod spire].