Grossuana thracica Glöer & Georgiev, 2009

Georgiev, Dilian, 2011, New localities of four Bulgarian endemic Hydrobiidae species (Mollusca: Gastropoda: Risooidea), ZooNotes 2011 (16), pp. 1-4 : 3

Grossuana thracica Glöer & Georgiev, 2009

Distribution in Bulgaria: Species known only from the type locality – the source of a small river emerging from Chirpan Bunar cave near village of Bolyarino, Upper Thracian Lowland ( Glöer & Georgiev 2009).

Material examined: 17 adults (2 males dissected) and 2 juveniles, 11.06.2010, and 8 adults, 19.12.2009, spring at Tri Voditsi fish farms near the base station of the farms, near village of Hadzievo, water temperature 14ºC, oxygen 6 mg /l, UTM KG96 Angel Tsekov leg. ; 4 shells, 08.06.2010, deposits of the stream inside the Chirpan Bunar cave , D. Georgiev leg.

Diagnosis: According to Glöer & Georgiev (2009) G. thracica differs from G. codreanui (Grossu, 1946) and G. angeltsekovi Glöer & Georgiev, 2009 in the penis morphology (the penis of the first species is not strongly tapered as it is in G. thracica , and in the second the penis is more tapered than it) and the shell of G. codreanui is glossy vs. silky in G. thracica . The aperture of G. codreanui is rounded oval and not angled at the top, as it is in G. thracica .

Discussion: The species G. thracica was described from the area where the water emerging from Chirpan Bunar cave. Our finding of shells into the cave stream deposits indicates that there is cave population of this species or at least part of the cave waters are coming from surface where other populations live.