Thelephora versatilis and Thelephora pseudoversatilis: two new cryptic species with polymorphic basidiomes inhabiting tropical deciduous and sub-perennial forests of the Mexican Pacific coast

Thelephora is a genus of ectomycorrhizal basidiomycetes with basidiomes of varied shape which has been poorly studied in tropical ecosystems. In this paper, we present Thelephora versatilis and Thelephora pseudoversatilis, two new species collected in the same localities of deciduous and sub-perennial tropical forests of Jalisco, Mexico. Basidiomes of both species are brownish gray to violet brown with clavarioid-mesopodal, sub-resupinate or completely resupinate growth forms. In turn, phylogenetic analyses using nrDNA ITS sequences showed that these species are not closed related, nevertheless they are part of a well-supported clade conformed by several species of Thelephora, Tomentella and some undescribed Thelephorales. Morphological segregation of these species was attained by analyzing spore and hyphae characters using a wide sample. Significant statistical differences between the new species were observed regarding spore size, spine size and context hyphae width. This work exemplifies the relevance of integrating both morphological and molecular data, as well of the use of an appropriate sample size in order to discriminate among morphological cryptic species.