A phylogenetic and taxonomic revision of sequestrate Russulaceae in Mediterranean and temperate Europe

A comprehensive morphological and genetic study of type material and new collections of sequestrate Russulales species formerly belonging to the genera Arcangeliella, Elasmomyces, Gymnomyces, Hydnangium, Hymenogaster, Macowanites, Martellia, Secotium and Zelleromyces is here undertaken, for the purpose of providing a complete taxonomical revision of sequestrate Russulaceae species in the Mediterranean and temperate regions of Europe. As a result, seven distinct taxa in the genus Lactarius and 18 in the genus Russula are identified. Six of them are new species: L. populicola, L. subgiennensis, R. bavarica, R. candidissima, R. hobartiae and R. mediterraneensis, and seven represent new combinations: L. josserandii (equivalent to Zelleromyces josserandii), L. soehneri (equivalent to Hydnangium soehneri), R. candida (equivalent to Hydnangium candidum), R. cerea (equivalent to Hydnangium cereum), R. messapica var. messapicoides (equivalent to Macowanites messapicoides), R. meridionalis (equivalent to Zelleromyces meridionalis) and R. neuhoffii (equivalent to Hydnangium neuhoffii). Twenty-two of the 25 taxa are illustrated, while descriptions, microscopy images, as well as extensive information on the ecology, chorology and phylogeny for all taxa are provided. A key is further included to facilitate their identification.