Rongeurs de la localité éocène de Cos (Tarn-et-Garonne, Quercy, France). Comparaison avec les rongeurs de localités de la transition Éocène inférieur/Éocène moyen

Rodents from the Eocene locality of Cos (Tarn-et-Garonne, Quercy, France). Comparison with rodents localities transition lower Eocene/middle Eocene. This article describes new fauna Quercy) whose primates were first studied and published (Godinot et al. 2021) Among these poorly diversified rodent assemblage, smallest species is assigned to Eogliravus wildi. All Hartenberger, 1971 are redescribed here their diagnoses emended. Two specimens designated as a small-sized indeterminate theridomorph. The largest most abundant represents Theridomorph genus Masillamys namely M. cosensis n. sp. analysis its morphological morphometric variability enables highlight high upper premolars, whereas molars lower. compared late Ypresian early Lutetian Masillamys. It more derived evolutionary grade than mattaueri 1975, Mas de Gimel (Hérault; MP10) especially by slightly larger size, less stage that Messel (Hesse; MP11), still weaker hypocone relative protocone on molars. also occurs in Viélase (Aveyron). These pointe toward time interval comprised between European reference levels MP10 MP11, near Ypresian-Lutetian transition, contribute discussion about biochronology this interval.