Caucasocressa schmalzi Hausdorf and Falkner, 2001

Hausdorf, Bernhard, 2003, Revision of the genus Caucasocressa from the eastern Pontic Region (Gastropoda: Hygromiidae), Journal of Natural History 37 (21), pp. 2627-2646 : 2641-2642

Caucasocressa schmalzi Hausdorf and Falkner, 2001

(figures 2, 17–19)

Caucasocressa schmalzi Hausdorf and Falkner, 2001: 45, pl. 6, fig. 1, pl. 7, fig 1. Type locality: ‘Vil. Artvin: rocky hill south of Demirkent, w-slope with Junipero-Pinetum and dry grassland, 1200– 2000 m alt., GF32’, Turkey.

Caucasocressa corrugosa Falkner in Hausdorf and Falkner, 2001: 48, pl. 6, fig. 2, pl. 7, fig. 3. Type locality: ‘Vil. Artvin: rocky hill south of Demirkent, w-slope with Junipero-Pinetum and dry grassland, 1200– 2000 m alt., GF32’, Turkey.

Caucasocressa perspectiva Falkner in Hausdorf and Falkner, 2001: 49, pl. 6, fig. 3, pl. 7, fig. 2, pl. 8, figs 2–3. Type locality: ‘Vil. Artvin: rocky hill south of Demirkent, 2000 –2300 m alt., GF32’, Turkey.

Shell (figures 17–19). Strongly depressed conical; with 5–5.75 convex whorls; teleoconch with wrinkled growth ridges, partly granular; whitish, usually with a brownish band below the periphery and one above the periphery; sometimes the bands are more or less obsolete; body whorl rounded; aperture elliptical or almost circular; upper insertion of the peristome distinctly descending; peristome sharp, slightly or distinctly expanded, with a more or less strong whitish internal rib; umbilicus wide, taking about 15–25% of the shell breadth.

Measurements. Demirkent, 1200– 2000 m alt. (N = 4): D= 16.4–17.5 mm, B = 17.0 mm; H= 8.1–10.4 mm, B = 9.3 mm; D/H=1.66–2.02, B =1.83. Demirkent, 2000 –2300 m alt. (N =8): D= 13.5–14.4 mm, B =14.0 mm; H= 7.1–9.5 mm, B = 8.2 mm; D/H=1.49–1.99, B =1.71.

Remarks. Caucasocressa schmalzi differs from the other Caucasocressa species in the wider umbilicus. See also C. phasiana .

The measurements of the distal sections of the genitalia were listed by Hausdorf and Falkner (2001).

The specimens from Demirkent, 2000 –2300 m alt. (C. perspectiva, figure 19), constantly differ from those from Demirkent, 1200–2000 m alt., in the smaller shells (see measurements) with a wider umbilicus (20–25% of the shell breadth versus 15–20%). Further investigations are necessary to decide whether these differences are altitudinal modifications, or in how far the populations are genetically distinct and the morphological differences indicate a subspecific differentiation.

Distribution and material (figure 2). C. schmalzi is known only from the mountains near Demirkent.

Turkey: V. Artvin: rocky hill south of Demirkent, W-slope with Junipero-Pinetum and dry grassland, 1200– 2000 m alt., GF 32 (det. anat.; holotype of C. schmalzi ZMH 2880; holotype of C. corrugosa ZMH 2881; paratypes of C. corrugosa FAL); rocky hill south of Demirkent, 2000–2300 m alt., GF32 (holotype of C. perspectiva ZMH 2882; paratypes of C. perspectiva ZMH 2883; FAL).