Freshwater fungi in the karst plateau wetlands from Guizhou Province, China: taxonomic novelties in Melanommataceae (Pleosporales).

Abstract

Three isolates of interest were collected during an investigation of freshwater fungi from wetlands in the karst regions of Guizhou Province, Southwest China. Phylogenetic analyses using ITS, LSU, SSU, and tef-1α gene regions have revealed the placements of these isolates in Melanommataceae (Pleosporales, Dothideomycetes). Based on the morphological and phylogenetic evidence, three new species are introduced: Byssosphaeriachishuiensis sp. nov., Camposporiumguizhouense sp. nov., and C.aquaticum sp. nov. Byssosphaeriachishuiensis is sister to B.villosa and forms a basal branch of Byssosphaeria within Melanommataceae. Byssosphaeriachishuiense is similar to B.villosa in ascal size but differs in the ascomata and ascospore sizes, and the ascospores lack appendages. Camposporiumaquaticum is sister to C.guizhouense, and they form a distinct lineage within the genus. Morphologically, C.aquaticum resembles C.guizhouense in its conidial shape but differs in conidial size. Additionally, PHI analysis is performed to further reveal that C.aquaticum and C.guizhouense have no significant recombination with related taxa. Neobyssosphaeria is synonymized under Byssosphaeria, and accordingly, Byssosphaeriaclematidis comb. nov. is proposed to accommodate Neobyssosphaeriaclematidis. The descriptions, illustrations, and notes of the novel taxa are provided along with an updated phylogenetic tree of Melanommataceae. Two synopses of the species in Byssosphaeria and Camposporium are also provided.