Telamonioid Cortinarius species of the C-puellaris group from calcareous Tilia forests

Four species belonging to the Cortinarius puellaris group are presented, including the two new species C. biriensis, C. subpuellaris and the recently described C. puellaris. Based on type studies, it is shown that the fourth species in the group should be named C. intempestivus (=C. cristatosporus). The species co-occur and are all studied mainly from SE Norwegian calcareous Tilia forests, but at least some of them also occur in Quercus(-Carpinus) forests in temperate-mediterranean areas of C-S Europe, and are apparently widespread and much overlooked. These are all tiny, small, ochre-redbrown telamonioid cortinarii with strongly to spiny ornamented spores. Phylogenetically, the taxa are well-distinguished by 8 to 22 ITS differences. Together with two taxa only known from ectomycorrhizal ITS sequences, they constitute an apparently well-supported Glade with uncertain affinity.