Summary:
Subgenus Dermocybe. Cortinarius croceus is a variable species showing variations in size and shape of the fruiting body and color of cap, stem and gills - gills are never bright orange (as in Cortinarius cinnamomeus), (Hoiland). Other features in Hoiland''s concept are brown cap, often with olivaceous tints, lemon-yellow to mustard-yellow gills (now and then with olivaceous or orange tint), yellowish, grey-brown, or reddish brown veil, and pale yellow cortina. |Siegel(2) gives the following helpful aid to diagnosis (with Latin italicized): "This widespread and common Dermocybe is fairly easy to identify when you have a large collection of young to old specimens; older specimens by themselves can be nearly indistinguishable from similar species. The cap color is generally cinnamon brown to orange-brown but can be dark brown to olive-brown or even reddish brown in age. The mustard yellow to greenish yellow color of the young gills (often best observed when still in button stage) is the most helpful identifying feature. However, the gills quickly become more orange in age, leading to confusion with the very similar C. cinnamomeus group." |The following description is derived (except where noted) from Hoiland(1). Moser''s concept of Dermocybe crocea could be somewhat different. |Kauffman(2) reported Cortinarius fucatophyllus Lasch-Ricken from Oregon and Hoiland gives C. fucatophyllus (Lasch) Fr. as a synonym of C. croceus, but the online Species Fungorum, accessed December 31, 2015, gives Cortinarius fucatophyllus (Lasch) Fr. as a synonym of C. cinnamomeus.

Cap:
1.4-5.6(6.1)cm across, convex, hemispheric, flat or umbonate; "first olivaceous-yellow with yellow-brown center or olivaceous yellow-brown all over, then pale to dark yellow-brown, olivaceous-brown, reddish brown, or hazel-brown, the margin usually more or less olivaceous-yellow"; radially fibrillose-felty, sometimes with minute squamules [fine scales], especially toward margin, seldom somewhat silky

Flesh:
in cap pale yellow, pale ochraceous-yellow, or pale ochraceous-grey, in stem "yellow to ochraceous, more olivaceous towards the base, seldom with an orange tint"

Gills:
adnexed to adnate; "first lemon-yellow to mustard-yellow, now and then with an olivaceous or orange tint, then dirty yellow to cinnamon-brown"; the edges somewhat paler and sometimes slightly serrulate

Stem:
3-8cm x 0.3-1cm, solid to somewhat fistulose [hollow]; "ground color sulphur-yellow, pale ochraceous, or pale ochraceous-grey, the top usually more yellow"; "silky-fibrillose, with more or less significant grey-brown to reddish brown veil remnants, sometimes as prominent slanting belts, sometimes only as weak threads", "the base with whitish yellow, pale olivaceous-yellow, or seldom pale orange-yellow mycelial felt"

Veil:
"yellowish, grey-brown, or reddish brown", cortina pale yellow

Odor:
with a slight smell of iodoform (Hoiland), typically has a radish odor (Trudell)

Microscopic spores:
spores (5.5)6.5-9(10) x (3.5)4-5.5(6) microns, oval, elliptic or amygdaloid [almond-shaped], punctate, yellow brown; basidia 2- or 4-spored, 20-31 x 5-6.5 microns, colorless or with bright yellow, granular content; gill edge fertile or sterile, with clavate, thin-walled, colorless cheilocystidia, 8-19 x (3)4.5-8 microns

Spore deposit:
[presumably brownish]

Notes:
Cortinarius croceus is a European species reported at least in WA (Jumpponen). Collections from BC are deposited at Pacific Forestry Centre. It has been reported from ID by Andrew Parker, pers. comm. A collection from BC had DNA that matched closely with some DNA used by Cortinarius experts for this species, (D. Miller, pers. comm.).

EDIBILITY

Synonyms and Alternate Names:
Cortinarius fucatophyllus (Lasch) Fr.
Cortinarius incognitus Ammirati & A.H. Sm.
Dermocybe crocea (Schaeff.) M.M. Moser
Dermocybe incognita (Ammirati & A.H. Sm.) Ammirati