Compléments à l'étude des rongeurs (Mammalia, Rodentia, Cricetidae, Eomyidae, Sciuridae) du gisement karstique de Blanquatère 1 (Miocène moyen, sud de la France)

Blanquatere 1 is the filling of a fissure opened in a limestone that had already provided a rich fauna (more than 6300 isolated teeth, 33 species) of small mammals including mainly rodents among which several new species of Cricetidae and Gliridae, referred to the Middle Miocene. The present paper brings an addition to this fauna with the description of the Cricetidae Eumyarion, Democricetodon, and Pseudofahlbuschia, of the Eomyidae Ligerimys et Keramidomys, and of the Sciuridae Spermophilinus and Heteroxerus. This highly diverse fauna must be definitely considered as a reference for the first part of the Middle Miocene (MN 4/5) in South Western Europe. It testifies of the occurrence of both new taxa and allochtonous ones, as the gerbillid Dakkamys sp. the occurrence of which being likely related to the closure of the Tethys in the Middle East during the Langhian. The co-occurrence of Ligerimys and Keramidomys is also documented as the oldest one. This fauna also illustrates the interest of karstic fissure fillings when they are exceptionally rich: they can deliver remains of species either very rare or of short duration.