ESPECIES NUEVAS DE RUTSTROEMIA, (ASCOMYCOTINA, SCLEROTINIACEAE) DE TIERRA DEL FUEGO, ARGENTINA.

Species of Rutstroemia Karst. recorded for the Andean-Patagoman and Fuegian forests (Argentina) are: R. megalospora, R. microsperma, R beaglensis nov sp and R nothofagi nov sp The concept of the genus here accepted includes species with a complex excipulum and an evident substratal stroma, but the gelatinization of the excipulum is not stressed, due to the variability observed in collections of the same species in identical habitat and localities The new species are described and illustrated. [ABSTRACT FROM AUTHOR]