An ophiosphaerella-like species was collected from dead stems of a grass (Poaceae) in Northern Thailand. Combined analysis of LSU, SSU and RPB2 gene data, showed that the species clusters with Lentithecium arundinaceum, Setoseptoria phragmitis and Stagonospora macropycnidia in the family Lentitheciaceae and is close to Katumotoa bambusicola and Ophiosphaerella sasicola. Therefore, a monotypic genus, Poaceascoma is introduced to accommodate the scolecosporous species Poaceascoma helicoides. The species has similar morphological characters to the genera Acanthophiobolus, Leptospora and Ophiosphaerella and these genera are compared.