New fungal genus, three novel species and one new record from mangroves, with reclassification of Melanconiella (Melanconiellaceae) species

Mangrove ecosystems, located in the land-sea interface, host a diverse array of fungi. In this paper, we introduce a novel genus, three novel species and one new record of fungi collected from mangrove environments in Pranburi, Prachuap Khiri Khan, Thailand. We establish <i>Pseudomelanconiella</i> as a new genus in Melanconiellaceae, to accommodate <i>Pseudomelanconiellamangrovei</i>, a saprobe from submerged decomposing wood of <i>Avicenniamarina</i>. Phylogenetic analysis indicates its close relation with <i>Septomelanconiella</i>, but they differ in the morphology of the conidia. Additionally, our analysis of Melanconiellaceae led to the reclassification of <i>Melanconiellaloropetali</i> to <i>Sinodisculaloropetali</i> and synonymizing <i>Sinodisculacamellicola</i> and <i>Melanconiellacamelliae</i>. This paper also introduces two other novel species: <i>Peroneutypahibisci</i>, a saprobe found on <i>Hibiscustiliaceus</i> and <i>Pseudochaetosphaeronemabruguierae</i> from <i>Bruguieracylindrica</i>, the first species in this genus reported as a mangrove fungus. A new record of <i>Rimoramangrovei</i> from <i>Ceriopstagal</i> is also reported. These discoveries emphasize the rich fungal diversity in mangrove ecosystems supporting further exploration of this unique environment.