Psilocybe caeruleorhiza

ABSTRACT

Psilocybe caeruleorhiza is described as a new, bluing, wood-rotting species from the midwestern United States fruiting in the late fall and winter. Morphological features place it in Psilocybe section Cyanescens or Semilanceata but near section Aztecorum based on micromorphological characters (i.e., ellipsoid to subellipsoid spores and ventricose-rostrate to langeniform cheilocystidia) while it most closely resembles P. ovoideocystidiata macroscopically. This new species can be distinguished from similar species by its stature and thin, subcortinate partial veil which leaves no annulus. Multigene phylogenetic analysis (nrITS, nrLSU, rpb1, rpb2, tef1) supports the novelty of the species and placement in section Aztecorum. A full description is provided along with photographs of fresh specimens and phylogenetic analysis.