Mycoenterolobium aquadictyosporiumsp. nov. (Pleosporomycetidae, Dothideomycetes) from a freshwater habitat in Thailand

A study of freshwater fungi in Thailand led to the discovery ofMycoenterolobium aquadictyosporiumsp. nov. Evidence for the novelty and placement inMycoenterolobiumis based on comparison of morphological data. The new species differs from the type species,M. platysporum, in having shorter and wider conidia, and fromM. flabelliformein having much longer and wider conidia. The hyphomycetous genusMycoenterolobiumis similar toCancellidiumbut differs in the arrangement of conidial rows of cells at the attachment point to the conidiophores. The conidia of the former are made up of rows of cells, radiating in a linear pattern from a single cell attached to the conidiophore, while inCancellidium, adherent rows of septate branches radiate from the conidiophore.Cancellidiumconidia also contain branched chains of blastic monilioid cells arising from the conidia, while these are lacking inMycoenterolobium. At maturity inMycoenterolobium, the two conidial lobes unite and are closely appressed. Phylogenetic analyses based on a combined LSU, SSU, ITS,TEF1-alpha, andRPB2loci sequence data support the placement ofMycoenterolobium aquadictyosporiumclose to the family Testudinaceae within Pleosporomycetidae, Dothideomycetes. The novel speciesMycoenterolobium aquadictyosporiumis described and illustrated and is compared with other morphologically similar taxa.