Bivalves from the upper carboniferous of Chubut, Argentina

Abstract

?Bivalves from the upper carboniferous of Chubut, Argentina?. Bivalves from the ?lower section? of the Tepuel Group, in the Central Patagonian Basin are here described and figured. Seven new species are proposed: Palaeoneilo amosi, Quadratonucula parva, Leptodesma variabilis, Shizodus paucus, Sanguinolites freytesi, Sanguinolites turneri and Myofossa antiqua. Other eight species are left nomina aperta because of insufficient material and diagnostic elements; they are: Phestia sp. IV, Phestia sp. V, Nuculopsis? sp., Naiadites? sp., Promitilus? sp. I, Streblochondria? sp. Prothyris? or Citothyris sp. and Megadesmus? sp. Finally, a previously described species: Phestia tepuelensis González (1969) has been identified. The constitutive elements of this bivalve fauna show both, nordic and gondwanic affinities. Most of them are associated with the brachiopod Levipustula levis, that indicates a Late Carboniferous age.