Parallelism in the evolution of dental pattern and systematic implications: The case of Protechimys major Schlosser, 1884 (Theridomyinae, Rodentia, Mammalia) and its associated rodents

Abundant remains of Protechimys major Schlosser (1884) (Rodentia, Theridomyinae) from Mas-de-Pauffié (Lot, France; standard–locality MP26, e.g., BiochroM’1997; Early Chattian) are described and their morphological and dimensional variability are analyzed. At this locality, and also at Les-Milles (Bouches-du-Rhône), P. major is associated with a few teeth of Archaeomys-Blainvillimys sp. Due to this scarcity and to similar evolutionary trends in the pattern of lower molars, it is not possible to find accurate features likely to distinguish Protechimys from Archaeomys or advanced Blainvillimys, but lines of research are given. Their co-occurrence with Issiodoromys pauffiensis Vianey-Liaud (1976) is documented at localities with different depositional conditions; together with the analysis of precise and focused samples made in the limited outcrop, it contributes to demonstrate the temporal homogeneity of the MP26 rodent assemblage from Mas-de-Pauffié.