Fossil polecat Mustela putorius and Mustela eversmanii (Carnivora: Mustelidae) cranio-dental remains from the Pleistocene record in South-Eastern France and comments on Mustela lutreola skull l’Observatoire

Abstract

Among Pleistocene carnivore communities, the smallest species are often the least well documented. This imbalance in knowledge between large and small carnivores is often the result of a less rich paleontological record for the latter, or difficulties in identifying them, particularly post-cephalic remains. However, these small species are highly informative, particularly when it comes to characterizing paleoenvironmental contexts. Among these, the polecats Mustela spp. are mustelids of prime importance, as discrimination between the typical Mustela putorius and the steppe one Mustela eversmanii contributes to the recognition of ancient ecosystems. We present here a synthesis of data concerning polecats in South-Eastern France and Principality of Monaco. This morphometric study, based on unpublished data (Les Auzières n° 1, Aven des Planes n° 1, Abri Moula, Grand Abri aux Puces, Grotte de l'Observatoire) and a bibliographical synthesis (including Coulet des Roches and Aven de l'Arquet), aims to document the criteria of differential diagnosis between the two taxa. The revision of the skull l’Observatoire cave site at Monaco, assigned to Mustela lutreola at the beginning of the 20th century, has revealed several diagnostic features. Compared with the remains of the polecat Mustela spp. we have produced an initial grid of cranio-dental criteria for specific identification. In addition, since the chronological framework covers the last 100 millennia (MIS 5 to Holocene), we are attempting here to qualify the morphometric evolution of polecats in a diachronic framework where chronoclimatic variations can have a significant impact on odonto- and osteological proportions.