CONTRIBUTION TO THE KNOWLEDGE OF THE FOSSIL FUNGI RECORD BASED ON PALYNOMYCOLOGICAL STUDIES FROM THE EL FOYEL GROUP, ÑIRIHUAU BASIN, PALEOGENE FROM PATAGONIA ARGENTINA

Spores, conidiophores, and hyphae of fossil fungi recovered from nine outcropping siltstone and shale samples belonging to the Troncoso, Salto del Macho, and Río Foyel formations in the El Foyel Group at the Río Foyel Section, are described and illustrated. Representatives of 16 genera were recognized. Among the 26 species described, one is proposed as a new species, Inapertisporites lacrimaformis. Amerospores are the most abundant type of spores recovered. Based on the palynostratigraphical analysis of the non-pollinic (fungal) remains, a Paleogene age for the El Foyel Group is suggested. Of the three formations, Troncoso shows the highest abundance and diversity of fungal remains, which is believed to be representative of a period of optimal climatic conditions characterized as warm temperate and humid, probably related to the Middle Eocene Climate Optimum (MECO). Based on the paleoeological preferences of the specimens recovered from the El Foyel Group, a riparian or lacustrine environment in a woodland setting is inferred.