Two new genera of gymnopoid/marasmioid euagarics
Ronald H. Petersen, Karen W. Hughes
Abstract
Two new genera, Paramycetinis and Pseudomarasmius , are placed phylogenetically within the /omphalotaceae among genera allied with Gymnopus . Paramycetinis comprises two Antipodal taxa related to Mycetinis . Both Paramycetinis species are characterized by luxuriant rhizomorphs, with basidiomata arising occasionally as side branches but also separately from rhizomorphs. Pseudomarasmius accommodates four new species plus four others previously placed in Marasmius . Pseudomarasmius encompasses significant basidiomatal variation, but nrLSU- and ITS-based phylogenies support its taxa in a monophyletic clade that occupies a position related to some Rhodocollybia. All Pseudomarasmius and Paramycetinis species are described (or redescribed) and illustrated. Both genera exhibit characters also found in other superficially similar lineages, making non-molecular based diagnoses of genera in the /gymnopus/marasmiellus clades difficult.