Mustelids (Carnivora, Mammalia) from Monte Tuttavista fissure fillings (Early and Middle Pleistocene; Orosei, Sardinia): Taxonomy and evolution of the insular Sardinian Galictini

The insular environment of Sardinia is renowned for its extensive palaeontological Palaeogene record, extending from the Eocene until recent times. In Sardinia, one of the most important localities for Quaternary faunas is the fillings of the karst fissures of the Monte Tuttavista site complex, which contain an impressive amount of fossil remains of around 70 vertebrate taxa. Several studies that have examined the network of the karst fissure cavities and their fossils have revealed some issues regarding the biochronological ordering, as well as some peculiarities in the recovered faunal associations (such as the presence of several carnivores). In this study, we analysed the record of the two large mustelids from this site, the genera Pannonictis and Enhydrictis. Our analyses point out several singular morphological and morphometric features of these taxa that suggest their attribution to two new species, Pannonictis baroniensis nov. sp. and Enhydrictis praegalictoides nov. sp. The proportions and the robust morphologies of P. baroniensis resemble those of other European taxa, such as P. pliocaenica, although other dentognatic and cranial features exclude a conspecific identity with previously known taxa. Conversely, E. praegalictoides represents the earliest member of the genus and shows a mixed pattern of derived features that are shared with the peculiar E. galictoides recovered from other Middle-Late Pleistocene Sardinian localities, as well as other more primitive characteristics that do not occur in this endemic mustelid. Considering the controversial debate regarding the evolutionary history of the tribe Galictini, the record of these new endemic species expands our knowledge of the systematics and the biogeography of the galictines and enriches the diversity of the tribe during the Early and Middle Pleistocene.