Cumberlandica wombeyanensis, Shea & Colgan & Stanisic, 2012

Shea, M., Colgan, D. J. & Stanisic, J., 2012, 3585, Zootaxa 3585, pp. 1-109 : 32

Cumberlandica wombeyanensis n. sp.

( Figs 7H; 8H; 9H; 10G; 11G)

Etymology. Named for the type locality.

Diagnosis. Shell very small, brown, weakly biconcave with tightly coiled whorls. Protoconch sculpture of low, widely spaced, narrow spiral cords, and widely spaced radial ribs, beginning on the final quarter of the protoconch and becoming more pronounced toward the protoconch-teleoconch boundary. Teleoconch sculpture of numerous, widely spaced radial ribs. Umbilicus widely open.

Type material examined. Holotype. AM C.319717, Wombeyan Caves west of Mittagong. Ivy covered slope next to shed, diagonally opposite office, behind cabin on west side of Wombeyan Creek, southern NSW (34° 18.51´S, 149° 58.08´E), 3.ix.1992, coll. M. Shea. Paratypes. Wombeyan Caves: AM C.157314, AM C.355273, AM C.353420, AM C472881 .

Description. Shell very small, light-brown, biconcave with a weakly depressed spire. Whorls 4.00–4.62, tightly coiled, the last descending in front. Sutures impressed. Shell diameter 4.08–4.57 mm (mean 4.33 mm), height 2.31–2.48 mm (mean 2.37 mm), H/D 0.52–0.58 (mean 0.54). Protoconch flat, of 1.25 whorls, diameter 0.6–0.8 mm. Protoconch sculpture consisting of 36 low, widely spaced, narrow spiral cords and widely spaced, orthocline to prosocline prominent radial ribs, beginning on the final quarter of the protoconch and becoming more pronounced toward the protoconch-teleoconch boundary. Teleoconch sculpture of numerous, prominent, quite uniformly spaced, slightly sinuate, orthocline to opisthocline radial ribs. Ribs on body whorl 95–119 (mean 105), every second rib weaker, width of interstices on the first teleoconch whorl equal to width of four to less than width of six ribs; on the penultimate whorl equal to width of four to less than six ribs; each rib with two or more overlapping periostracal blades. Interstitial sculpture of low prominent microradial ribs and low, weaker microspiral cords forming beads at their intersection; number of microradials between ribs on the first teleoconch whorl 8–10; on first quarter of body whorl 10–12; microspirals very low. Aperture narrowly ovately-lunate. Parietal callus prominent, translucent. Umbilicus wide U-shaped, diameter 1.07–1.32 mm (mean 1.14 mm), D/U 3.39–4.05 (mean 3.81). Based on seven measured adults.

Anatomy unknown.

Distribution and habitat. Wombeyan Caves limestone outcrop, Southern Highlands, NSW; found in damp places among the limestone karst in eucalypt forest and woodland, living on the underside of logs and in rock piles.

Remarks: This is the southern-most known species in Cumberlandica and the most geographically isolated of the group. It is endemic to the Wombeyan limestones and is distinguished from other species in the genus by the less sunken spire, more numerous and bolder apical radial ribs, less numerous and more widely spaced teleoconch ribs, and usually proportionately narrower umbilicus.