New data on morphology, physiology, and geographical distribution of Lignomyces vetlinianus , its identity with Lentinus pilososquamulosus , and sufficient phylogenetic distance from Le. martianoffianus

Several specimens of putative Lentinus pilososquamulosus (including the type specimen) and Le. martianoffianus from Siberia and the Russian Far East associated with different hosts and collected during the past two decades were studied. Morphological examination of the studied specimens showed a close similarity to specimens of Lignomyces vetlinianus , a species originally described from Central Europe, but later discovered in European Russia, the Caucasus (Abkhazia), and the Urals. Cultures of Li. vetlinianus were characterized by growth and morphology, and their adaptation to various temperatures was evaluated. Growth rate of the strains at 25 °C varied between 1.2 and 3.1 mm/day; the majority of them could survive freezing at −20 °C and grew at temperature ranging from 5 to 35 °C. Comparative culture characters, mating compatibility, and ITS sequencing revealed that the specimens earlier identified as Le. pilososquamulosus or Far East Russian Le. martianoffianus (misapplied name) were identical to Li. vetlinianus . It was shown that the distribution area of Li. vetlinianus extends from Central Europe to the South (Caucasus) and through Western Siberia to the Russian Far East. Since several attempts of Le. pilososquamulosus holotype sequencing were unsuccessful, an epitype of this taxon, represented by a successfully sequenced old topotype specimen, was proposed. Le. pilososquamulosus is considered as synonym of Li. vetlinianus , following the principle of priority. A molecular study of true Le. martianoffianus (type specimen) supported its conspecificity with Panus lecomtei .