Habitat requirements of the pulmonate land snailsTrochulus oreinos oreinosandCylindrus obtususendemic to the Northern Calcareous Alps, Austria.
The habitat needs and potential threats toTrochulus oreinos oreinos(Wagner 1915) andCylindrus obtusus(Draparnaud 1805) were assessed by comparing vegetation maps and our own records. We selected four sites from which we had adequate samples and for which exact vegetation maps were available: the mountains Hoch-schwab, Schneealpe, Rax and Schneeberg. Both taxa prefer open dry alpine grassland with diggable soil and/or stones.T. oreinos oreinosis restricted to subalpine and alpine boulder societies andCaricetum firmae. WhileC. obtususdwells on several communities of plants, it seems to be bound to unconsolidated stony ground. As both taxa prefer naturally forest-free areas, they are not affected by structural changes of the habitat, such as reforestation caused by the abandonment of grazing and the shift of vegetation zones. But it has to be considered thatT. oreinos oreinosandC. obtususare limited by microclimatic factors, as they prefer cooler habitats. The mountains Schneealpe, Rax and Schneeberg, reaching barely 2000 m in height, are on the climatic limit of the species distribution. Therefore, the investigated taxa are vulnerable to the upward shift of climate zones.T. oreinos oreinosshows striking similarities in its habitat preference to the Swiss endemicT. biconicus, as both taxa prefer the same dry alpine habitats which are quite different to those of other representatives of the genus, which prefer damp habitats.
3 Zoological Department, Museum of Natural History Vienna, Burgring 7, 1010 Vienna, Austria.
Michael
M
Duda
luise.kruckenhauser@nhm-wien.ac.at , 1 Zoological Department, Museum of Natural History Vienna, Burgring 7, 1010 Vienna, Austria.
Luise
L
Kruckenhauser
elisabeth.haring@nhm-wien.ac.at , 1 Zoological Department, Museum of Natural History Vienna, Burgring 7, 1010 Vienna, Austria.
Elisabeth
E
Haring
helmut.sattmann@nhm-wien.ac.at , 3 Zoological Department, Museum of Natural History Vienna, Burgring 7, 1010 Vienna, Austria.
Helmut
H
Sattmann
Alpine endemics; Cylindrus obtusus; Gastropoda; Mollusca; Trochulus oreinos; climate change; habitat preferences