Les araignées (Arachnida, Araneae) de la réserve naturelle nationale de Chastreix-Sancy (Puy-de-Dôme)

A first survey of spiders in the Chastreix-Sancy national nature reserve including the montagne du Mont (espace naturel sensible) was carried out in 2021 and 2022. Eight sampling stations have been defined: raised bog, sphagnum bog, beech-fir forest, dry perennial grassland, subalpine meadow, mountain heath as well as a forest wetland and a recent grassland after spruce clear-cutting restoration on the montagne du Mont area. In addition, surveys on various habitats were carried out (alder-ash forest, willow forest, beech forest, subalpine bog, scree, riparian forest, etc.) and made it possible to largely complete this inventory. Overall 302 species of spiders (including three at the generic level) have been identified. In view of their rarity, their degree of specialization and/or the level of threat that weighs on them, 23 species can be considered remarkable, including 14 on the list of threatened spider species (eight EN [endangered] including two specifically in the Massif central and six NT [near-threatened]). Forty species are cited for the first time from Auvergne, four from Auvergne-Rhône-Alpes. The species observed are mainly associated with open environments. The community associated with peat bogs and wetlands are among the most remarkable. The ungrazed dry perennial lawns contribute to the list of the reserve by a rich community and with xerophilic affinity. Mountain species, some of Pyrenean origin, have been identified. Some, present only on the summits, are threatened in the medium term by climate change. Finally, the absence of specialist and relict taxa among the forest corteges seems to reflect the strong anthropogenic pressure suffered by these environments in the 19th century.