THE FIRST PALYNOLOGICAL RECORD OF THE SAUCE GRANDE FORMATION (PENNSYLVANIAN-CISURALIAN)AT THE AUSTRALES RANGE, BUENOS AIRES PROVINCE, ARGENTINE

Abstract

The first palynological assemblage recovered from a sample of the Middle Member of the Sauce Grande Formation is presented. Palynomorphs are small (among 20 ?m - 50 ?m) and poorly preserved. Exines are fragmented, highly carbonized (dark gray or black in colour) and affected by framboidal pyrite. Eleven species of palynomorphs are described and illustrated: nine trilete spores (Apiculiretusispora sp., Cyclogranisporites sp., Granulatisporites austroamericanus Archangelsky and Gamerro, Lophotriletes sp., Horriditriletes sp. cf. H. gondwanensis (Tiwari and Moiz) Foster, Horriditriletes sp. cf. H. ramosus (Balme and Hennelly) Bharadwaj and Salujha, Raistrickia sp., Lundbladispora sp., Cristatisporites sp.), one pollen grain and one acritarch. The assemblage is referred to the Late Pennsylvanian -Cisuralian based on the stratigraphic range of the species recognized that additionally are widely distributed in Gondwana (e.g., Chacoparaná, Paraná, Paganzo, Karroo). The dominance of spores, and the presence of framboidal pyrite and an acritarch suggest a marine littoral palaeoenvironment for the assemblage.