Pontohoratia smyri, Vinarski & Palatov & Glöer, 2014

Vinarski, Maxim V., Palatov, Dmitry M. & Glöer, Peter, 2014, Revision of ‘ Horatia’ snails (Mollusca: Gastropoda: Hydrobiidae sensu lato) from South Caucasus with description of two new genera, Journal of Natural History (J. Nat. Hist.) 48 (37 - 38), pp. 2237-2253 : 2247-2248

Pontohoratia smyri sp. nov.

( Figure 5B ; 7D )

Type locality

Anatolia Lake in the Novoafonskaya Cave, Abkhazia (see Table 1).

Type series

ZIN, accession number 1 (the holotype), and 2 (seven paratypes) . 25 paratypes in the collection of the Museum of Siberian Aquatic Mollusks (Omsk State Pedagogical University), accession number 07-033. The snails from the type series were collected in 2009 .

Other material studied

39 specimens sampled in 2010 in the collection of Dmitry Palatov (Moscow) .

Holotype shell dimensions at 3.25 whorls (in mm)

SH 1.2; SW 1.4; SpH 0.6; BWH 0.9; AH 0.7; AW 0.6.

Morphological description

Shell very small (up to 1.4 mm), almost planispiral, yellowish-white or corneous, with very wide body whorl and relatively low spire. Shell walls moderately thick. Umbilicus wide and deep, opened. Whorls number up to 3.50. Whorls convex, separated by deep suture. Aperture angular, visibly deflected.

Penis simple, without a lobe (see Figure 5B ).

Etymology

The species is named after Givi Smyr, a speleologist, who discovered the Novoafonskaya Cave in 1961.

Differential diagnosis

Pontohoratia smyri differs from P. birsteini by much lower spire and much wider body whorl (see Figure 7 ). SW is 1.15–1.45 times more than SH, whereas in P. birsteini this ratio is around 1.00 (see Table 3). Whorls number in P. smyri is lower than in P. birsteini . The honeycomb-like pits on the protoconch surface of the new species are somewhat wider than those of P. birsteini (see Figure 4 ).

Distribution and ecology

Pontohoratia smyri is known from the type locality and the closest vicinities of the Novoafonskaya Cave (floodplain of the Psyrtskha River). Perhaps, the original habitat of P. smyri is an underground brook inflowing to the lake Anatolia and the shells were carried out by its flow. The same is true also for empty shells of this species found in several springs in the floodplain of the Psyrtskha River. Empty shells of two other gastropod species were collected along with P. smyri : Paladilhiopsis shadini Starobogatov, 1962 and Belgrandiella (?) abchasica Starobogatov, 1962 . The invertebrate community of this cave is very specific and includes some crustacean taxa: amphipods Niphargus spp. (Niphargidae) and Anopogammarus sp. (Typhlogammaridae) , and decapod Troglocaris (Xiphocaridinella) fagei Birstein, 1939 .

Figures

Figure 4. The protoconch sculpture of the species studied. Scale bars 100 μm.

Figure 5. The penis morphology in Caucasian ‘Horatia’. (A) Motsametia borutzkii (Tskhal- Tsiteli Cave); (B) Pontohoratia smyri; (C) ‘Horatia’ sokolovi = Pontohoratia birsteini (Nizhneshakuranskaya Cave). Scale bar 0.5 mm.

Figure 7. Shells of Motsametia and Pontohoratia. (A, B) Pontohoratia birsteini comb. nov., Tsebeldinskaya Cave; (C) Pontohoratia birsteini comb. nov., Niznheshakuranskaya Cave; (D) Pontohoratia smyri, holotype (Novoafonskaya Cave); (E) Motsametia borutzkii, topotype (Tskhal-Tsiteli Cave). Scale bars 300 μm.