Species delimitation in the Gloeocystidiellum porosum-clavuligerum complex inferred from compatibility studies and nuclear rDNA sequence data

Abstract

Gloeocystidiellum porosum and Gloeocystidiellum clavuligerum are corticioid homobasidiomycetes with minor morphological differences and are generally regarded as a complex of closely related taxa. To infer phylogenetic relationships and to aid in species delimitation, sequences of the internal transcribed spacer 2 and the 5′ end of the large subunit nuclear ribosomal DNA were obtained for 25 representatives of the species complex. Inter-and intracompatibility tests between cultured representatives for all specimen groups were performed. Results of phylogenetic analyses based on DNA sequences were congruent with compatibility results. Gloeocystidiellum clavuligerum consists of two distinct taxa, and G. porosum includes at least two intersterile groups of uncertain taxonomic status.