Morphology and ecology of Didymium subreticulosporum

A new description of Didymium subreticulosporum is provided that highlights its unique taxonomic characters-a discontinuous peridial wall, lack of did ymioid capillitium, and the presence of an irregular membranous structure i nside the sporotheca, filled with crystals. This species is considered succ ulenticolous due to its consistent fruiting on Opuntia cladodia in early st ages of decay and restriction to this microhabitat. Spore dispersal is appa rently by cactophilic Drosophila flies.