Morphological and phylogenetic evidence for Russula butyroindica sp nov (Russulaceae) from the Indian Himalaya

A novel and first species belonging to Russula subg. Archaea was collected from West and South districts of Sikkim and is proposed here as Russula butyroindica. It is typically characterized by its butter-to straw-colored, eroded and deeply sulcate pileus surface that occasionally changes to reddish orange with maturity; distant, thick and brittle lamellae of unequal lengths; concolorous (to pileus) stipe; chalky white spores; globose to ellipsoid basidiospores [4-5.09-5.59-6.7(7) x 3.4-4.07-4.35-5(6) mu m]; pileipellis of both slender and inflated hyphal extremities and pileocystidia and occurrence under Castanopsis sp. Morphological details of this undescribed species are provided along with the phylogenetic placement based on nrITS phylogeny.