Species ofAlatosporaandMargaritisporahave been studied in pure culture. The conidial morphology of 33Alatosporaisolates was examined. The conceptof Alatospora acuminatais broadened to embrace strains with a high percentage of unbranched and triradiate conidia as well as those with large conidia with an arcuate axis and narrow branch insertion.Alatospora constrictais neotypified, and a new generic name is introduced to accommodate a species with similar conidia but different conidiogenesis.Margaritispora aquaticais neotypified andM. monticolais neotypified and recombined in a new genus.