Russula griseopurpurata, a novel taxon of Russula subsect. Cyanoxanthinae (Russulaceae) from India

Abstract

A new species of Russula subsect. Cyanoxanthinae within subg. Heterophyllidiae, growing under the Shorea robusta tree in West Bengal and Meghalaya, India, is described based on macro- and micromorphological characteristics and molecular phylogeny. The taxon is distinguished macroscopically by having a medium-sized pileus coloured greyish to purple that cracks at maturity; the presence of lamellae furcations near the stipe; and microscopically by fusiform to lanceolate hymenial cystidia on the sides of the lamellae with a long appendage, globose to subglobose basidiospores with subreticulate ornamentation, and habitat in association with the Shorea robusta plant. A comprehensive morphological description, phylogenetic tree, illustrations of microstructures, and photographs of the novel taxon are provided.