Parafuscosporella garethii, a new freshwater taxon, is described and illustrated from submerged decaying twigs in a Thai community forest located in Chiang Mai Province. The species is recognized as the third species in the genus, and markedly differs from those previously accepted in the genus by its conidial size and shape and having two forms of conidiogenous cells. Phylogenetic analysis based on combined LSU, SSU and RPB2 sequence data place P. garethii in Fuscosporellales, Hypocreomycetidae, Sordariomycetes. The novel taxon is compared with morphologically and phylogenetically similar species in the genus and a taxonomic comparison to accepted Parafuscosporella species is also provided.
Key words -E.B. Gareth Jones -freshwater fungi -Fuscosporellaceae -phylogeny -taxonomy
IntroductionParafuscosporella (Fuscosporellaceae, Fuscosporellales, Hypocreomycetidae and Sordariomycetes) was introduced by Yang et al. (2016) with P. moniliformis and P. mucosa, as the type and second species in the genus, respectively. These two species were isolated from unidentified submerged twigs in a freshwater stream of Prachuap Khiri Khan Province, Thailand. The genus is characterized by partly immersed, partly superficial, septate, hyaline to pale brown mycelium; semi-macronematous, mononematous, branched, monoblastic, globose to subglobose, smooth-walled, hyaline conidiophores; and conidia that are ellipsoidal to broadly obpyriform, 1-septate, with a septum near the base, sometimes with a protuberance, and a smooth, dark brown to black, pale brown at basal cell (Yang et al. 2016).During a mycological survey of microfungi at a small stream located in a community forest in Chiang Mai Province, northern Thailand, P. garethii was found on submerged decaying twigs and is described as a new species here. The new taxon differs from other Parafuscosporella species in having two conidiophore types and in conidial shape and size. Phylogenetic evidence place the taxon in Fuscosporellales with strong bootstrap support. Parafuscosporella garethii is therefore introduced as a third species in the genus and is a novel freshwater taxon from Thailand.