MICROFITOPLANCTON ORGÁNICO DEL CRETÁCICO INFERIOR DE LA CUENCA DE SAN LUIS. PARTE I: SCENEDESMACEAE Y CHLOROCOCCACEAE

Abstract

The systematic study of organic microphytoplancton from the Aptian-Lower Albian La Cantera Formation, San Luis Basin, central western Argentina, is presented. Species of the genera: Scenedesmus, Tetrastrum, Crucigeniella? and Tetraedron, all belonging to the families Scenedesmaceae and Chlorococcaceae, are described. This is the first record of Tetrastrum, Crucigeniella? and Tetraedron fossils from the Lower Cretaceous of Argentina. The microphytoplanctonic assemblage was associated to a lacustrine environment that includes evaporitic facies. KEY WORDS. Argentina. San Luis. Lower Cretaceous. Organic microphytoplancton. Scenedesmaceae. Chlorococcaceae.