Abstract:
Mycoleptodiscus includes plant pathogens, animal opportunists, saprobic and endophytic fungi. The
present study presents the first molecular phylogeny and revision of the genus based on four loci, including ITS,
LSU, rpb2, and tef1. An extensive collection of Mycoleptodiscus cultures, including ex-type strains from the CBS,
IMI, MUCL, BRIP, clinical isolates from the USA, and fresh isolates from Brazil and Spain, was studied morphologically
and phylogenetically to resolve their taxonomy. The study showed that Mycoleptodiscus sensu lato is
polyphyletic. Phylogenetic analysis places Mycoleptodiscus in Muyocopronales (Dothideomycetes), together with
Arxiella, Leptodiscella, Muyocopron, Neocochlearomyces, and Paramycoleptodiscus. Mycoleptodiscus terrestris,
the type species, and M. sphaericus are reduced to synonyms, and one new species is introduced, M. suttonii.
Mycoleptodiscus atromaculans, M. coloratus, M. freycinetiae, M. geniculatus, M. indicus, M. lateralis (including
M. unilateralis and M. variabilis as its synonyms) and M. taiwanensis belong to Muyocopron (Muyocopronales,
Dothideomycetes), and M. affinis, and M. lunatus to Omnidemptus (Magnaporthales, Sordariomycetes). Based on
phylogenetic analyses we propose Muyocopron alcornii sp. nov., a fungus associated with leaf spots on Epidendrum
sp. (Orchidaceae) in Australia, Muyocopron zamiae sp. nov. associated with leaf spots on Zamia (Zamiaceae) in the
USA, and Omnidemptus graminis sp. nov. isolated from a grass (Poaceae) in Spain. Furthermore, Neomycoleptodiscus
venezuelense gen. & sp. nov. is introduced for a genus similar to Mycoleptodiscus in Muyocopronaceae.
