The Rudist Fauna of the Cárdenas Formation, Maastrichtian, San Luis Potosí State, Mexico

摘要: A Maastrichtian rudist fauna composed of the radiolitids Biradiolites aguilerae Bose, B. Cardenasensis Huasteca ojanchalensis (Myers), Tampsia floriformis Myers, and Trechmannites rudissimus (Trechmann), hippuritids Caribbea muellerriedi (Vermunt) Praebarrettia sparcilirata (Whitfield) sensu lato, plagioptychids Coralliochama gbohemi Bose Mitrocaprina tschoppi (Palmer) is described from Cardenas Formation in San Luis Potosi State, Mexico. Abundant fossil material excellent preservation a number specimens allowed observation both internal external shell characters their ontogenetic eco-phenotypic variability. The description some hitherto insufficiently known species has been enhanced and/or completed, making easier subsequent identification allowing unequivocal generic assignation. Two new genera, Trechmannites, are proposed for two already radiolitids. exhibits continuously exposed sequence vicinity Cardenas. Thus, precise stratigraphic location all localities associations, ranging early to late Maastrichtian, possible.