Abstract
During our ongoing investigations of freshwater fungi in Thailand, Cylindroconidiis aquaticus gen. et sp. nov. is described in family Sclerococcaceae (Eurotiomycetes), based on morphological characters and analyses of LSU, SSU and ITS sequence data. Its closest relatives are Rhopalophora and Fusichalara minuta. The new genus is characterized by mononematous, unbranched conidiophores, polyblastic, terminal or intercalary conidiogenous cells, and cylindrical,1-septate conidia. It is the first report of freshwater fungi encountered in Sclerococcaceae.