Inocybe leiocephala, a species with an intercontinental distribution range - Disentangling the I. leiocephala - Subbrunnea - catalaunica morphological species complex

Abstract

Sequence data and morphological characteristics of specimens determined as Inocybe leiocephala were compared with six type specimens. We confirm I. leiocephala, I. lind-rothii, I. subbrunnea, I. fuscescentipes, I. subpaleacea and I. catalaunica as separate independent species. All species except I. subpaleacea and I. catalaunica were shown to have a broad intercontinental distribution range. Inocybe leiocephala has its main distribution in arctic-alpine and subalpine habitats, and I. lindrothii in hemiboreal - boreal zones. Inocybe subbrunnea is confined to nutrient rich, often more calcareous soils and mixed coniferous forests. Both I. fuscescentipes and I. subpaleacea, described from the alpine zone, also grow in boreal forests. Inocybe catalaunica is a species well separated from I. leiocephala, I. lindrothii and I. subbrunnea in molecular data and it appears to be more related to I. tjallingiorum and I. phaeoleuca despite macro-morphological similarities to the I. leiocephala group. The new species I. ohenojae is described here based on material from the alpine zone in Canada. The new combination Inocybe lindrothii is proposed and an epitype is designated. Inocybe saponacea is regarded as a synonym of I. lindrothii. A key to the species is provided.