Notes on the Italian distribution of Dolomedes plantarius (Clerck, 1757), species assessed for the IUCN red list (Araneae: Pisauridae)

Abstract

The great raft spider, Dolomedes plantarius, is a semi-aquatic spider species with an Eurosiberian distribution. As a result of habitat loss and degradation, in 1996 the species was classified as Vulnerable in the IUCN Red List of Threatened Species, but since then the status has never been updated. We present the frame of the existing knowledge on the distribution of this rare spider species in Italy, based on literature data and on original records gathered in recent years. Finally, we discuss the conservation value of the Italian populations, in light of their peripheral position within the species range and in light of the future reduction of the bioclimatic range of the species due to climate and land cover changes associated with anthropic disturbance.