Morphological and phylogenetic evidence for two new species of Russula subg. Heterophyllidia from Guangdong Province of China

Abstract

Two new species of Russula subg. Heterophyllidia from Guangdong Province of China were described and illustrated based on morphological characters, and their identity supported by molecular phylogeny. R. luofuensis is morphologically characterized by a grayish yellow to brownish orange pileus center with a purplish gray to grayish magenta margin, a surface that is cracked and broken into small golden-brown patches, subglobose to broadly ellipsoid basidiospores with warts fused in short or long chains and a suprapellis composed of hyphal extremities with inflated, ellipsoid or globose cells and attenuated terminal cell. R. subbubalina is distinguished by the blanched almond to dark salmon pileus that is cracked with age, subglobose to broadly ellipsoid basidiospores with wart fused in short or long chains and frequently connected by line connections, a suprapellis with hyphal ends composed of inflated or ellipsoid cells and attenuated terminal cell, and pileocystidia that are mainly clavate and sometimes with round or ellipsoid appendage. The phylogenetic analyses based on ITS-nrLSU-mtSSU-TEF1 dataset were performed using maximum likelihood and Bayesian analysis. In terms of morphological features and molecular data, the former species belongs to subsect. Virescentinae, whereas the latter comes under subsect. Heterophyllinae.