An Asian edible mushroom, Macrocybe gigantea: Its distribution and ITS-rDNA based phylogeny

Abstract

An updated phylogeny of Macrocybe, a rare pantropical genus, is presented, and new insights regarding the distribution of M. gigantea are given. At the end of last century, this genus was segregated from Tricholoma on morphological and molecular data yet it is still being treated under Tricholoma. In the phylogenetic analysis based on ITS-rDNA, we observed the monophyletic lineage of Macrocybe from the closely related genera Calocybe and Tricholoma. Six collections of M. gigantea, a syntype, re-collected and sequenced from Pakistan, clustered with Chinese and Indian collections which are available in GenBank under Tricholoma giganteum, an older name. The purpose of this work is to support Macrocybe as a separate genus from Tricholoma and Calocybe using ITS-rDNA based phylogeny.