Rongeurs (Mammalia, Rodentia) du Miocène de Beni-Mellal

Jean-Jacques Jaeger

Cite this article: Jaeger J.-J., 1977. Rongeurs (Mammalia, Rodentia) du Miocène de Beni-Mellal. Palaeovertebrata 7 (4): 91-125.

Abstract

The rodent fauna of Beni-Mellal is characterized by the abundance of ctenodactylids and cricetids. The latter are represented by four distinct species, among which a new form. Dakkamys zaiani nov. gen., nov. sp. is described. A detailed morphological analysis shows that, contrary to that which had been established before, « Cricetodon ›› atlasi Lavocat, 1961, is not closely related to any European form known; this species is attributed, in consequence, to the new genus Mellalomys. A simple biometric analysis has shown that the genus Myocricetodon Lavocat, 1952, is represented in this locality by two distinct species. The systematic homogeneity of the Beni-Mellal cricetids is also demonstrated: they can, as a matter of fact, all be referred to the subfamily Myocricetodontinae. The definition of this subfamily is completed. The sciurids and glirids are also reviewed in the light of new systematic and biogeographic information established ln Europe. A new species of Atlantoxevus from the early Pleistocene of Morocco, A. huvelini nov. sp., is described. It is probably the descendant of A. tadlae from Beni-Mellal. Biogeographic analysis leads one to consider this fauna as the result of geographic isolation in the Maghreb since the late Oligocene or the early Miocene. In particular no direct European influence can be discerned. Stratigraphic considerations resulting from the discovery of new localities in North Africa lead to the confirmation of the ante-Vallesian age of this fauna and to its parallelism with the faunas of La Grive in Western Europe and Fort Ternan in East Africa. The peculiar geologic nature of this locality is discussed.