Boros István (szerk.): A Magyar Természettudományi Múzeum évkönyve 52. (Budapest 1960)

Agócsy, P. ; Pócs, T.: Data to the mollusk fauna of Hungary

One of our more interesting finds concerns the showing of Bythinella austriaca and Sadleriana pannonica, living beside each other in the small rivulets feeding the artifical lake in Jávorkút. The two species meet only at this one point, their areas being otherwise, as shown also by the map, well separated and defined. And as a matter of fact, we have found Sadleriana pannonica, also in the warm waters of Kácsfürdő at the southern foot of the Mts. Bükk, — an unusual occurrence for this species, inhabiting explicity cold springs and brooks. Fig. 1. The ranges of Bythinella austriaca Frauenfeld (1) and Sadleriana pannonica Frauenfeld (2) in Hungary. Bythinella occurs also in Western Hungary, at a point not shown on the map, in the Mts. Kőszeg. The white signs indicated by ,,a" designate data known up to now, the black ones indicate the new localities found by the authors. The signs, with the same interpretation, recur also on fig. 2 and 3. The highest points of the Mts. Pilis, — the Vaskapu above Pilisszentkereszt, Kétbükkfanyereg, the Feketekő above Pilisszentlélek and Simon-halála — hid numerous montane snail species in their rocky forests and on their open cliffs. The new localities emphasize further the connections of the northeastern half of the Hungarian Central Mountains and their Transdanubian parts. Several montane species range to the Mts. Pilis in the SW, from over the Carpathians (Cochlodina orthostoma, Clausula cruciata, Goniodiscus ruderatus, Trichia unidentata, etc.). This is a parallel occurrence with the range of numerous flowering plants, supporting the existence of the Central-Danubian floristic divide, traced back to climatic causes. In this connection, we may mention the following vascular plants : Helleborus purpurascens, Valeriana tripteris, etc. The Mts. Bakony is less well known from a malacological point of view. There is, for instance, a slope covered by dense shrubs above the shore of the