Two new species of genus Lactarius Pers. (Russulaceae) from Arunachal Pradesh, India

Lactarius Pers. is one of the most frequently encountered ectomycorrhizal genera of the family Russulaceae. Because of its cosmopolitan nature, several taxa belonging to its three subgenera, Lactarius subg. Lactarius (Fr. ex J.Kickx f.) Kauffman, L. subg. Russularia (Fr.) Kauffman, and L. subg. Plinthogalus (Berk.) Hesler & A.H.Sm., have been documented worldwide portraying its diversity. Routine macrofungal explorations concentrating on Lactarius in two districts of Arunachal Pradesh (West Kameng and Tawang) have accounted for many species in temperate to subalpine forests. Recent observations have revealed two interesting species belonging to subgenera Lactarius and Russularia. Morphological features along with nrITS-LSU based phylogenetic analysis inferred these two species as new to science. Lactarius kamengensis sp. nov. (subg. Lactarius) is characterized as a medium-sized Lactarius with bitter to acrid taste, pale yellowish, vaguely zonate pileus, scrobiculate stipe, white latex turning pale yellowish and occurrence under Castanopsis (D.Don) Spach. Whereas, Lactarius madhuriensis sp. nov. is a unique high-altitude species belonging to subg. Russularia with brownish orange coloured, umbonate pileus, and watery white latex that turns yellowish.