In or Out of the Checklist? DNA Barcoding and Distribution Modelling Unveil a New Species of Crocidura Shrew for Italy

The genus Crocidura (Eulipotyphla, Soricidae) is the most speciose genus amongst mammals,i.e., it includes the highest number of species. Dierent species are distinguished by skull morphology,which often prevents the identification of individuals in the field and limits research on these species'ecology and biology. We combined species distribution models and molecular analyses to assess thedistribution of cryptic Crocidura shrews in Italy, confirming the occurrence of the greater white-toothedshrew Crocidura russula in the northwest of the country. The molecular identification ascertainedthe species' presence in two distinct Italian regions. Accordingly, species distribution modellinghighlighted the occurrence of areas suitable for C. russula in the westernmost part of northern Italy.Our results confirm the role of Italy as a mammal hotspot in the Mediterranean; additionally, theyalso show the need to include C. russula in Italian faunal checklists. To conclude, we highlight theusefulness of combining dierent approaches to explore the presence of cryptic species outside theirknown ranges. Since the similar, smaller C. suaveolens may be displaced by the larger C. russulathrough competitive exclusion, the latter might be the species actually present where C. suaveolenshad been reported previously. A comprehensive and detailed survey is therefore required to assessthe current distribution of these species.