Revising museum collections help to fill knowledge gaps in the Italian mammal fauna: the case of Sorex araneus and Sorex antinorii from South Tyrol

In Italy, after the elevation to species rank of the Valais shrew Sorex antinorii, all collection specimens from the museums previously attributed to the Eurasian shrew Sores araneus were assigned to the former species. But no official verification of this "automatic" species attribution has ever been attempted. In our work we did the revision of 14 specimens of the Sorex araneus group from the Autonomous Province of Bolzano-South Tyrol in the north-east of Italy, by using molecular markers. The study was based on cytochrome b sequences, that allowed to assign unambiguously the analyzed specimens to one of the Sorex species. Among these South Tyrolean Sorex records we unexpectedly found only one specimen of S. antinorii, whereas the other 13 specimens could all be assigned to S. araneus. In this way, we were able to prove the occurrence of both S. antinorii and S. araneus for South Tyrol. Our work furthermore shows that S. araneus in Italy was never "gone" and it has to be added to the list of Italian mammals again. These findings thus stress the importance of a revision of museum collections by using modern technologies, to estimate the correct level of diversity of the small mammal fauna at regional and national level and, as in the case of S. antinorii, to better define its actual northern distribution limit in the Alps.