Analisi dello smalto dentario di Microtus (Tyrrhenicola) (Arvicolidae, Rodentia, Mammalia) dal Monte Tuttavista (Sardegna, Italia): nuove prospettive biocronologiche

The Microtus (Tyrrhenicola) is an endemic Pleistocene and Holocene, arvicolid (Rodentia, Mammalia) of Sardinia and Corsica, but on his origin and evolution numerous problems and controversies still stay. A detailed knowledge of the evolutionary tendencies of this arvicolid could reveal extremely useful for the improvement of biochronology of the Sardinian faunal complexes. Measurements of the enamel thickness of the first inferior and third superior molars of the populations of Tyrrhenicola recovered in nine different fissure fillings of the Monte Tuttavista (Orosei, Western Sardinia) have been performed and the index of enamel differentiation has been calculated. The results of the first inferior molars have been compared with different continental subgenera of the genus Microtus and the tendency to the reduction of the thickness of I enamel in the back part of the molar triangles has been evidenced also for M. (Tyrrhenicola).