 A multi-gene molecular analysis published in 2008 demonstrated that species then distributed in the genera Lactarius and Russula actually consisted of four distinct lineages. The subsequent reorganization of Russulaceae species — a taxonomic change needed to make Russula and Lactarius monophyletic — required that a new type species be defined for Lactarius, since the previous type, L. piperatus, belonged to the clade that will be transferred to genus Lactifluus. A proposal to conserve Lactarius with L. torminosus as the type was accepted by the Nomenclatural Committee for Fungi and passed at the 2011 International Botanical Congress. The change minimizes "taxonomic disruption", allowing most of the common and well-known Lactarius species to retain their names.
