Bythiospeum hrustovoensis, Glöer & Grego, 2015

Glöer, Peter & Grego, Jozef, 2015, New subterranean freshwater Molluscs from Bosnia & Hercegovina (Mollusca: Hydrobiidae), Ecologica Montenegrina 2 (4), pp. 307-314 : 310

Bythiospeum hrustovoensis n. sp.

( Figs 13-17)

Holotype: from spring 1: shell height 2.1 mm, width 1.1 mm, HNHM 99423 .

Paratypes: 5 specimen (spring 1), HNHM 99424 , 2 specimen from spring 3 in coll. Glöer; 3 specimens from spring 3 in coll. Jozef Grego.

Locus typicus: Bosnian Fedeartion, Bihać district, Hrustovo, 1.5 km E of village, at bottom of valley below entrance of cave Hrustovačka pećina- spring 1 under dense vegetation coming from large debriss with sand deposits at bottom of spring zone and at side of spring rivulet; N44.674682°, E16.700246°; 04.05.2015 Jozef and Maroš Grego leg.

Remark: Between spring 1 (closest to cave entrance) and spring No. 3 150 m E of spring 1 is a spring No. 2 with cleaned out sediments, weak flow rate and stagnant water in a flooded cave entrance during our visit. The species had been found only in spring 1 and 3 so far ( Figs. 1, 6).

Etymology: Named after village of Hrustovo in which vicinity the locus typicus is located.

Description

Shell. The whitish and silky shell is elongate-conic with 5.5 convex whorls, apex blunt. The umbilicus is closed, aperture oval, slightly sinuated outer lip from lateral view. Axis of aperture inclined. Shell height 2.1–2.3 mm, width 1.0– 1.2 mm.

Differentiating features: Bythiospeum hrustovoensis n. sp. is smaller than B. blihensis n. sp. and B. plivensis n. sp. In B. hrustovoensis n. sp. the axis of aperture is inclined while it is in B. maroskoi n. sp. and B. petroedei n. sp. it is nearly vertical. In addition the outer lip of the aperture is only slightly sinuated.

Distribution: Only known from type locality.

Associated species: Ancylus fluviatilis O.F. Müller, 1774 .