Données nouvelles sur les mollusques (Mollusca, Gastropoda) du Parc national du Mercantour (France)

Since 2001, the molluscan fauna of the Mercantour National Park has been surveyed in the framework of a convention between the Park and the National Museum of Natural History (Paris). This has yielded 270 sampled localities representing 1094 data of species occurrences, of which 955 are situated within the Park. A total of 119 terminal taxa have been recorded from the Park, a quarter of which are of biological importance for France, confirming the high biodiversity value of the Park. At least 4 species, and possibly 6, are strictly endemic to the Park, with an additional 11 terminal taxa having most of their global populations within the Park. The peripheral zone is the richest part of the Park and the most important for the protection of remarkable species or subspecies, harbouring 93% of the total fauna and all but two of the (sub)endemic taxa. Here we provide new data on the distribution and ecology of 24 terminal taxa, some of which were previously only known from their original description, more than one century ago. Cochlostoma (Turritus) acutum (Caziot, 1908) is separated as an independent species from C. (T.) simrothi (Caziot, 1908), as well as Monacha (Eutheba) martensiana (Tiberi, 1869) from M. (E.) cemenelea (Risso, 1826). Clausilia euzieriana Bourguignat, 1869 is synonymised with Macrogastra (Pyrostoma) mellae mellae (Stabile, 1864), while former citations of this taxon are referred to M. (P.) mellae leia (Bourguignat, 1877). Chilostoma (Cingulifera) cingulatum liguricum (Kobelt, 1876) is transferred as a subspecies of Ch. (C.) frigidum (Mortillet, 1861) and is added to the French fauna. Arianta arbustorum vareliensis Ripken & Falkner, 2000 is added to the Italian fauna, as well as a mountainous species of Urticicola to which a name has yet to be applied. Evaluation of the IUCN criteria for redlisting concludes that Cochlostoma acutum, Macrogastra mellae leia and Chilostoma frigidum liguricum should be redlisted as VU D2.