Toxic Fungi of Western North America

by Thomas J. Duffy, MD

The genus Cortinarius in general

The genus Cortinarius has a variety of shapes, but the common feature is a spider-web like veil, the "cortina", in the early stages. The cortina later collapses on the stipe, usually leaving a band colored by rust-brown roughened spores. The genus is subdivided into a number of subgenera using cap and stipe features of dry or viscid and base of the stipe bulbous or non-bulbous. Added to these are pigmentary differences, microscopic cap features and differences in ultraviolet fluorescence. This genus, fortunately, has never been high on the list of edibles, except for Cortinarius (Rozites) caperatus, which has an atypical membranous ring.

Dr. Rolf Singer in his Agaricales 4th edition gave over the difficult task of Cortinarius classification to Dr. Meinhard Moser of the Institute for Microbiology (University of Innsbruck, Austria). (126) Dr. Moser placed the two toxic species considered Cortinarius orellanoides in the sub-genus Leprocybe, section Orellani. These species are dry-capped, usually 3-8.5 cm in cap width and fluoresce blue or blue-green under ultraviolet light. Cortinarius gentilis Fr., a species described from Europe by Fries, also occurs commonly in Western North America. This member of sub-genus Leprocybe may also contain orellanine or a similar toxin.