Microcondylaea bonelli (Férussac 1827) inhabits rivers in the northern and eastern region of the adriatic sea. Actual IUCN conservation status is VU (vulnerable), it is listed in Annex V of the Flora-Fauna-Habitat directive of the EU. Due to construction works, frequent severe flooding and habitat changes the species is in rapid decline in its whole area. Conservation status should therefore be altered to CR (Critically Endangered) and the habitats of the remaining populations especially in Croatia managed to stop the decline.

The junior authors collected in the Bükk Mountains in the rivulet in Kács a Bythinella species new to science. From this region only B. pannonica was known which is endemic to the southeastern part of the Northern Carapthian Mountains (Fehér et al. 2013). This rivulet is fed by two springs, a cold one and a hypothermal spring. Only in the hypothermal branch the new Bythinella sp., described here as Bythinella thermophila n. sp., occurs. Both species are in its shell shape very different from other Bythinella spp. known from Europe and Asia Minor so far. In addition to the description the shells of the holotype and paratypes are depicted, as well as the type localities and living specimens. For comparison a photo of B. pannonica is provided.

A new representative of a new genus and a new Bythinella species have been found in Macedonia, Sumia macedonica n. gen. n. sp. and Bythinella golemoensis n. sp. The shells of the holotypes and paratypes as well as the penis morphology are depicted.

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