Russula brunneoaurantiaca, a novel taxon of Russula subg. Crassotunicata from West Bengal, India, with morpho-molecular analysis and scanning electron microscopy

This paper describes a new Russula species, R. brunneoaurantiaca, from India with morphological and molecular sequence (nrITS) data, field pictures of basidiocarps, and comparisons with close relatives. Russula brunneoaurantiaca has a brownish orange pileus with a mucilaginous surface, sub-decurrent lamellae that are white to pale orange, a white stipe that turns yellowish brown to brown when bruised, a strong, unpleasant smell, globose to subglobose basidiospores (5.0-9.0 5.0-7.8 m) with an inamyloid suprahilar spot and ornamentation of small isolated conical warts, fusiform hymenial cystidia on gill sides (62.5-82 x 7.5-12.5 mu m) and lageniform to sub-lageniform cystidia with filiform apex near the gill edge (80-113 x 7.5-10 mu m), fusiform to spindle-shaped pileocystidia, and habitat in association with Castanopsis sp. A complete morphological description, photographs, and molecular sequence-based phylogenetic trees demarcating the position of the novel taxon are provided.