E-Flora BC: Electronic Atlas of the Flora of British Columbia

Summary:
Section Viscosae (Smith), Section Hygrocyboideae (Maas Geesteranus). Features include 1) a glutinous, faintly striate cap that is olive to olive brown to clove brown becoming blackish or sometimes dark grayish citrine becoming greenish brown, 2) white gills with a greenish tinge that are soon greenish gray and become spotted with reddish brown stains, 3) a very viscid, greenish yellow stem that is usually dingy purplish brown toward the base, 4) a strong cucumber or disagreeable odor, 5) growth in oak or pine woods, at low elevations in the fall, and 6) microscopic characters including cystidia that have one or more prominent thorn-like projections and are often quite irregular in shape. |Smith(1) emphasizes the cheilocystidia in differentiating from varieties of M. epipterygia given here: there are color differences, but colors are quite variable within the species. |Maas Geesteranus includes Smith''s M. griseoviridis as a subspecies of Mycena epipterygia, but wonders if supporting material found under pine rather than oak "near melting snowbanks in the mountains in the summer" was the source of the additional color description "dark grayish citrine becoming greenish brown in age" and could represent a different variety. He didn''t examine that material however, basing the variety on the type and another collection found under oak. [Those collections may represent Mycena nivicola, described later.] |The following is adapted from Smith''s description. |Maas Geesteranus also includes in his M. epipterygia var. griseoviridis Smith''s M. griseoviridis var. cascadensis which differs in more intense colors, habitat (conifer logs of Abies fir in WA), simple or seldom branched cystidia, and coarser excrescences of both cheilocystidia and terminal cells, but Maas Geesteranus is not sure whether it is an independent variety. |The name Mycena griseoviridis has been used in California for a spring snowbank species that was described in 2016 as Mycena nivicola. MykoWeb said in 2012 "In the past we have referred to this species as Mycena griseoviridis. Mycena nivicola [a provisional name at that time] from the Sierra Nevada differs in several respects from Smith''s original description of Mycena griseoviridis, which was based on material collected under oak in the fall in Michigan. These differences, along with DNA evidence, makes this taxon worthy of species recognition. The differences include a dissimilar habitat and fruiting season, a glabrous, not pruinose cap, lamellae lacking olivaceous tints, and a faint, rather than strong farinaceous odor and taste." (MykoWeb accessed April 7, 2012, Latin names italicized).

Smith reported Mycena griseoviridis from at least OR, QC, CA, MI, and TN. There is a Scott Redhead collection from just north of Hope, BC at the University of British Columbia (as M. griseoviridis) from a Populus tree October 14, 1973. At the University of Washington there is a collection from Skamania County, Washington on October 7, 1982 by S. Carpenter. Other collections are in spring and early summer and could represent Mycena nivicola.

Gills:
adnate, ascending, with slight decurrent tooth when old, close to subdistant, 16-22 reaching stem, moderately broad; white with a greenish tinge, soon greenish gray and becoming spotted with reddish brown stains, edges pallid

Stem:
(3)5-9cm x 0.1-0.25(0.35)cm, equal, round in cross-section or compressed, tenacious; "light dull green yellow" to "courge green", sometimes rather bright yellowish fading to pearly gray and usually dingy purplish brown toward base; very viscid, densely white pruinose overall at first, becoming bald and shining, base somewhat white-strigose

Odor:
strong of green cucumbers or more disagreeable

Taste:
strong of green cucumbers or more disagreeable

Microscopic spores:
spores 9-11 x 5-6.5 microns, elliptic, weakly amyloid, [presumably smooth]; basidia four-spored, 32-36 x 7-8 microns; pleurocystidia absent, cheilocystidia 30-60 x 6-11 microns, colorless, clavate at first but soon fusoid, with one to four long needle-like projections 15-30 x 2-3 microns, the projections simple or forked, the enlarged part of the cystidium sometimes covered with obtuse, irregular protuberances in addition to the needle-like projections (a few cheilocystidia are clavate and more or less contorted)

Spore deposit:
[presumably white to pale buff]