Najdba vrste Bythinella austriaca	(Gastropoda:
Hydrobiidae) na Goričkem (severovzhodna Slovenija)
RECORD OF BYTHINELLA AUSTRIACA (GASTROPODA: HYDROBIIDAE) AT GORIČKO (NORTH-EASTERN SLOVENIA)
Marjan VAUPOTIČ, Ulica generala Maistra 5, SI-9000 Murska Sobota, Slovenija; E-mail: marjan.vaupotic@guest.arnes.si
Hydrobiidae constitute one of the largest freshwater snail families in Slovenia. Many species are subterranean, many are endemic (Velkovrh 2003). Till now the distribution of Hydrobiid taxa in Slovenia has showed that they are absent only from its north-eastern part (Fig. 1). Vaupotič and Velkovrh (1997) reported only about a remainder of a shell from this part of Slovenia, which could not be precisely determined. They presume that the reason for a lack of Hydrobiidae snails in this region is in relation with the absence of limestone. Representatives of Hydrobiidae are mostly calciphiles.
The second reason seems to be that this area is too poorly malacologically researched. This can be seen in the accidental finding of Hydrobiidae at the time of the terrestrial snail sampling. During the inventarization of Vertigo angustior at Goričko (Vaupotič 2006), empty Hydrobiidae shells were found in two of the samples (a meadow near the Črnec stream, Krašči, Zg. Črnci, WM77 and a riverine forest along the Ledava river, Sv. Jurij, WM78). Both localities spread in the river basin of Ledava. In each sample, only one shell belonging to Hydrobiidae was found. According to the conchological signs (Bole 1969, Gloer 2002), it seems that the specimens belong to Bythinella austriaca (Frauenfeld 1859). Dr. Rajko Slapnik shares the same opinion. The zoogeographical distribution of this species is East Alpine and Carpathian.
It goes without saying that we must proceed with further intensive investigation of the distribution of Hydrobiidae snails in north-eastern Slovenia. Further research should be focused on finding living animals, given that such findings enable a more precise determination.
Literature
Bole J. (1969): Ključi za določevanje živali -Mehkužci. Inštitut za biologijo Univerze v Ljubljani in Društvo biologov Slovenije, 115 pp.
Fechter R., Falkner G. (1990): Steinbach's Naturführer: Weichtiere. Mosaik Verlag, München, pp. 124.
Glöer P. (2002): Die Süßwassergastropoden Nord-und Mitteleuropas. ConchBooks, Hackenheim, pp. 92-178.
Vaupotič M. (2006): Popis potočnega škržka (Unio crassus) in ozkega vrtenca (Vertigo angustior) s predlogom conacije Natura 2000 območja Goričko (SI3000221). (Projekt: »Zasnova conacij izbranih Natura 2000 območij« (7174201-01-01-0002) Phare čezmejno sodelovanje Slovenija-Avstrija 2003). Center za kartografijo favne in flore, Miklavž na Dravskem polju, 27 pp.
Vaupotič M., Velkovrh F. (1997): Prispevek k poznavanju favne mehkužcev (Mollusca) v severovzhodni Sloveniji. Acta Biologica Slovenica 41(1): 37-45.
Velkovrh F. (2003): Mehkužci - Mollusca. In: Sket B., Gogala M., Kuštor V. (Eds.), Živalstvo Slovenije. Tehniška založba Slovenije, Ljubljana, pp. 109-132.
Slika 1. Razširjenost hidrobid v Sloveniji. Figure 1. Distribution of Hydrobiidae in Slovenia.