L. Forró szerk.: Miscellanea Zoologica Hungarica 12. 1998 (Budapest, 1998)

Szinetár, Cs., Gál, Zs.; Eichardt, J.: Spiders in snail shells in different Hungarian habitats

MISCELLANEA ZOOLOGICA HUNGARICA Tomus 12. 1998 p. 67-75 Spiders in snail shells in different Hungarian habitats by Cs. Szinetár, Zs. Gál and J. Eichardt (Received May 28, 1998) Abstract: With the aim of examining the spider fauna, 7197 empty snail shells have been collected and examined from 12 collecting localities in Hungary. The 723 spiders found represented at least 37 species. Beside the 6 most frequent taxa (Pellenes nigrociliatus, Euryopis quinqueguttata, Heliophanus spp., Euophrys spp., Pellenes tripunctatus) several rare species were also found. Among these, Ballus rufipes (Simon, 1868) and Euophrys aperta Miller, 1971 are new to the Hungarian fauna. Keywords: spiders, overwintering, empty snail shells Introduction Numerous examples are known about arthropods using empty snail shells. For example, in the case of hermit crabs (Paguridae), mason bees (Osmia spp.) as well as caddis-flies (Trichoptera), this phenomenon is well known. In the case of some tropical spiders, there were reports on permanent snail shell and spider relation (Horn 1980). There is only a few data in the European literature on spiders living in snail shells. The majority of the references relate to the water spider {Argyroneta aquaticd), in which wintering in empty snail shells is a frequent phenomenon (Wagner 1894, Lampert 1904, Wesenberg-Lund 1939, Horn 1980). Some further publications are dealing with the relation between empty snail shells and jumping spiders (Salticidae) (Bellmann 1976, 1991, Horn 1980, Bauchhenss 1995). Studies of Horn (1980) and Bauchhenss (1995) showed that in the grassy associations where the empty shells of some snail species are occurring in high number, high percentage of shells (10-40%) are occupied by spiders. Among these, some jumping spider species (Salticidae) are the most frequent. Horn (1980) performed observations beyond the wintering period too and studied the breeding behavior of Pellenes nigrociliatus connected to the snail shells. Numerous xerothermic ecosystems are known in Hungary, where some thermophil snail species occur in large numbers. In this respect the most characteristic are the south-facing rocky swards on southern slopes of our mountains as well as the sandy grassland prairies of the Great Hungarian Plain. In these grass communities the empty snail shells can be found during the whole year on the soil surface. The most frequent species are Zebrina detrita and Helicella obvia. In the light of the above mentioned facts, it seemed promising to collect data on spider occupancy of shells, especially because such data collection has not been carried out in our country yet. We wanted to answer the following questions: 1. In what extent are the spiders using empty snail shells as shelters during winter? 2. Are the spiders living in snail shells only during the winter? 3. What kind of spider species could be collected effectively this way? 4. Which are those habitats where this method could be used effectively for faunistical data collection?