Regional catalogue of the spiders (Arachnida, Araneae) of Aosta Valley (NW Italy)

Abstract

We provide the regional catalogue of the spider species of Aosta Valley (NW Italy, Graian and Pennine Alps) based on literature records and original material collected from 2011 to 2013 in the frame of a collaboration project between the University of Torino and the Regional Museum of Natural Sciences of Aosta Valley. The revision of 1162 literature records scattered in 37 papers published between 1878 and 2015 provided a list of 382 species potentially occurring in this region. On the base of taxonomical and faunistic arguments discussed in the text, we here revise the literature and exclude 74 species from the list, of which seven of unlikely occurrence and 67 in need of verification. The original data here presented raise the total number of species occurring in this region to 384, grouped in 182 genera and 36 families. For each species reported in the catalogue, we provide new collection data, previous literature records, the known distribution and the habitat in which they occurred. Compared with other northern Italian regions and considering its extent, Aosta Valley presents a moderately high number of species, hosting 26% of the species recorded in Italy. In terms of species richness, linyphiids dominate with 99 species (26%), followed by gnaphosids (50 species, 13%), lycosids (45 species, 11%) and salticids (30 species, 7%). Wetlands host cumulatively the highest number of species, followed by shrublands, broadleaved forests and riparian habitats. Regarding chorotypes, most of the species have Palearctic distribution, followed by European and Holarctic species. Alpine endemic species represents 5% of the total.