LAS TORTUGAS CASIQUELIDIAS DE LAS CALIZAS LITOGRAFICAS TITONIANAS DEL AREA LOS CATUTOS, NEUQUEN, ARGENTINA

Abstract

CASICHELYDIAN TURTLES FROM THE TITHONIAN LITHOGRAPHIC LIMESTONE OF LOS CATUTOS AREA. NEUQUEN. ARGENTINA. The Tithonian lithographic limestone of the Vaca Muerta Formation (Late Jurassic) of Neuquén province, Argentina yielded cryptodiran (Eurysternum? neuquinum Fernández and Fuente, 1988) and pleurodian (Notoemys laticentralis Cattoi and Freiberg, 1961) turtles. Eurysternum? neuquina is tentatively referred to the Plesiochelyidae and placed in a new genus, Neusticemys. Neusticemys neuquina exhibits the shell of a pelagic sea turtle including an antero-posterior elongation of the carapace, extensive fontanelles between the pleural and peripheral bones, and elongate forearm (antebracial) elements that form a flipper. We suggest that both taxa inhabited offshore environments. The Los Catutos turtles belong to generic and perhaps family taxa different from those of the Kimmeridgian-Tithonian of Europe.