ABSTRACTComparative isozyme analyses were performed on three species ofTremellato test their utility as a taxonomic tool and to genetically characterize these fungi. A total of 28 enzymes were surveyed from 86 basidiocarps ofT. moriformis, 11 basidiocarps ofT. indecorata, and 35 basidiocarps ofT. globospora.Twenty-one enzymes (22 loci) retained sufficient activity to be useful in this survey. Twelve enzymes were monomorphic among all three species yet retained species-specific mobilities; of these only 1-glycerophosphate dehydrogenase showed too little interspecies variation to be useful taxonomically. Nine polymorphic enzymes were identified (10 loci); of these only the pair of electromorphs of alcohol dehydrogenase and one electromorph of isocitric dehydrogenase were common to two species.The predominance of monomorphic enzymes and the clear distinction of electromorphs between species suggests isozyme analysis is well suited as a taxonomic tool within the genus.