Neocotylidia gen. nov. (Hymenochaetales, Basidiomycota) Segregated from Cotylidia Based on Morphological, Phylogenetic, and Ecological Evidence.

Abstract

Taxonomic and phylogenetic studies of Cotylidia (Hymenochaetales, Basidiomycota) were performed. A phylogenetic estimate based on six genetic markers revealed that Cotylidia in the current sense includes species belonging to three distantly related clades in the Hymenochaetales. Based on morphology, phylogeny, and ecological habitat, the name Cotylidia s.s. is proposed for the first clade, including the type species C. undulata and C. carpatica. Neocotylidia gen. nov. is proposed for the second clade, which includes N. diaphana, N. fibrae, the new species N. bambusicola, and two accessions recorded as Cotylidia aurantiaca var. alba and C. aurantiaca. Contrary to the findings in earlier studies, C. pannosa demonstrated a weak grouping affinity with Globulicium hiemale, Hastodontia hastata, Atheloderma mirabile, Tsugacorticium kenaicum, Lawrynomyces capitatus, and Lyoathelia laxa. The morphological characteristics of Cotylidia s.s. are restricted to species with hymenial cystidia, pileocystidia, and caulocystidia, as well as a muscicolous habitat. Neocotylidia species differ from Cotylidia s.s. in the lack of pileocystidia and caulocystidia and substrate preference for soil or wood. Illustrated descriptions of the new species and genus, as well as an identification key to the worldwide species of Cotylidia s.l. are provided.