OSTRACODOS DE LA FORMACION CARMEN SILVIA, MIEMBRO SUPERIOR (MIOCENO INFERIOR), ISLA GRANDE DE TIERRA DEL FUEGO, ARGENTINA. PARTE I

Abstract

"The study of ostracodes from one sample of fue Upper Member of the Carmen Silva Formatíon is started. Fourteen species representing 13 genera are described. Four species are proposed: Cyamocytheridea rossiae nov. p., Copytus malomiarü nov. sp., Cytheropteron fueguensis nov. sp., Hemicutherura carmensílvaensís nov. sp. and one taxon has previously been proposed: Argenticytheretta miocenica Rossi de Carda 1969, Because of scarse material nine species have not been named. One of them has defíníte affínítes with an australian species: Kangarina sp, (Mckenzie, 1974). Two taxa are questionable placed in their respective genera. The microfauna is generally well preserved but it is poor in number of specimens. Most caparaces are moderately to strongly calcified and medium in length. The ostracodes appear to be closely related with microfaunas from the upper Míocene of Entre Ríos nnd Santa Fe and the Pliocene of R;o Negro provinces. This suggests a possible interchange north-south, Besides there are species which have close affinity with taxa from Chile, Brazil and Australia. The microfauna seerns to have inhabited shallow water environment."