Summary:
Subgenus Dermocybe. Features include dry, dull yellowish olive to dull olive-brown cap, olivaceous flesh; adnexed, broad gills that are olive to olive-brown; dull yellow to olive or olive brown stem; growth among Sphagnum; dark brown to fuscous olive KOH reaction on cap and dark brown KOH reaction on gills; and microscopic characters. Note that the Breitenbach(5) description gives ocher-brown to reddish brown cap surface and flesh. Cortinarius tubarius var. luteofolius has young gills distinctly yellow and stipe apex yellow.

Cap:
2.5-5cm across, obtusely bell-shaped becoming flat or flat-umbonate; dull yellowish olive (near "Isabella color") when young, becoming dull olive-brown ("tawny olive") or duller; "dry, appressed-fibrillose", margin lacerate when old, "sometimes sulcate-striate", (Ammirati), 1.5-5cm across, conic to hemispheric when young, later convex to flat and often with low, obtuse umbo, "margin incurved for a long time, even, acute"; ocher brown to reddish brown; "finely radially fibrillose to tomentose, sometimes slightly appressed-squamose when old", (Breitenbach)

Flesh:
in cap olivaceous (more or less "Isabella color"); in stem colored as in cap, darkening to olive-brown in base, (Ammirati), thin; light ocher to reddish brown, (Breitenbach)

Gills:
"adnexed, broad, close to subdistant"; at first dull light yellowish green ("reed yellow") to dull yellowish olive ("Isabella color") "becoming dingy dark yellow-brown to dull fulvous", (Ammirati), notched and narrowly attached, broad, 38-44 gills reaching stem, 3-6 subgills between neighboring gills; "olive to yellow-olive when young, later olive-brown"; "edges slightly crenate, in part paler than the faces", (Breitenbach)

Stem:
6-14cm x 0.6-1.2cm, equal; "dull yellow and not overlaid by a distinctly colored layer of fibrils", apex colored as young gills, when old stem between dull yellowish olive ("Isabella color") and dull olive-brown ("tawny olive") lower down; appressed-fibrillose, (Ammirati), 5-8cm x 0.3-0.7cm, cylindric, "stiff, flexible, solid when young, hollow when old"; "cream-yellow with an olive tint when young", later increasingly olive brown to reddish brown; "finely fibrillose over the entire length, base sometimes white-tomentose", (Breitenbach)

Odor:
slightly grass-like (Breitenbach)

Taste:
mild, rather unpleasant, (Breitenbach)

Microscopic spores:
spores 9.2-11.5 x 5-6 microns, in side view elliptic, ornamented, pale brown to pale fulvous, (Ammirati), spores 7.5-12 x 4.5-6.5 microns, oval to elliptic, weakly verrucose, light reddish ocher; basidia 4-spored, 23-34 x 7.5-9.5 microns, clavate, clamp connection at base, basidia colorless in KOH, without brown pigments; septa with clamp connections, (Breitenbach)

Spore deposit:
reddish brown (Breitenbach)

Notes:
Cortinarius tubarius in North America is primarily an eastern species (Ammirati(9)). Harrower(1) assigned a BC collection sequence 91 to Cortinarius tubarius. Morphological correlation is desirable. It is also found in Europe including Switzerland (Breitenbach(5)).

EDIBILITY

Synonyms and Alternate Names:
Dermocybe tubaria (Ammirati & A.H. Sm.) Ammirati