Summary:
Subgenus Phlegmacium. Cortinarius scaurus is a member of the Cortinarius scaurus group. Features of C. scaurus in the Brandrud description include 1) a viscid grayish to somewhat olivaceous brown cap (the center tinged darker brown and the young margin olivaceous gray to grayish green), 2) green to olivaceous brown gills, 3) a presumably dry stem that is bluish green to bluish gray then yellowish gray, with a marginate bulb that has pale yellowish green veil remnants, and 4) a lilac reaction of the flesh to Lugol''s iodine. The Brandrud et al. description is for the typical variety: they also describe var. sphagnophilus (Peck) Brandr. (differing from others in the lack of green color on cap margin and gills, usually darker brown cap, and growth preferentially in deep Sphagnum moss along bog rims) and var. herpeticus (Fr.) Quel. (differing in larger and greener fruit bodies, paler and when young greener cap, and blue-green gills, and growth preferentially in young forests). Kauffman(3) presents as separate species both of these, Cortinarius sphagnophilus Peck (for New York), and Cortinarius herpeticus Fr. (for Michigan and Washington). Cortinarius scaurus is not common.

Cap:
2.5-5(6)cm across, (hemi-)spheric, then flat-convex, sometimes with a low umbo; (pale) grayish-brown to somewhat olivaceous brown, at center tinged darker brown, margin pale olivaceous gray to distinctly grayish green when young; "viscid and somewhat greasy", "margin often with hygrophanous veins or drop-like spots, rarely with a complete hygrophanous zone at margin", (Brandrud), 2-5(7)cm across, "olive-green with brown spots in margin zone or completely brown (margin often darker)", (Moser), up to 6cm across, "dark brown on a chocolate brown ground", not very viscid, fibrillose-innately streaky (Courtecuisse), 3-6(8)cm across, convex, obtuse or broadly subumbonate [somewhat umbonate], at first with margin incurved, at length flat or depressed, commonly small, with width much less that length of stem; "Dresden-brown" at first or darker, at length "tawny"; viscid, bald, sometimes when dry spotted on disc from drying gluten, margin at first slightly fibrillose from the citrine-yellow cortina, even or short-striate on margin when old, (Kauffman), 5-7.5cm across, dark olive brown when young, fading to brownish tawny, (Stuntz), 2-6cm across, "convex; browny olive-green with brown spots near the margin" (illustration looks brown overall); greasy rather than glutinous, (Phillips)

Flesh:
whitish to brownish white, in stem pale blue-violet to bluish green, when young sometimes lilac when bruised, (Brandrud), +/- olivaceous or bluish-gray (Courtecuisse), moderately thick on disc, thin on margin, rather soft, moist; strongly tinged by the color of the cap; in stem "Russian-blue" except at pallid or soon whitish base, (Kauffman), not violet or lavender in cap, even when young, (Stuntz), "pallid with possible hints of violet" (Phillips)

Gills:
"crowded; green to olivaceous green, soon olivaceous brown", with a persistent olivaceous tinge towards top of stem, (Brandrud), olive-greenish to blue-greenish (Moser), olive (Courtecuisse), adnexed, becoming emarginate, crowded, narrow, 0.3-0.5cm; at first "mignonette-green" then "tawny-olive"; transversely rivulose [with river-like lines] at times, the edge entire, (Kauffman), lavender very soon becoming yellow-green, (Stuntz), "adnate; yellowish to olive-greenish", (Phillips)

Stem:
4-8cm x 0.5-0.8(1)cm, with more or less marginate bulb (up to 2cm wide); pale bluish green to bluish gray, then yellowish gray; glossy, veil at bulb margin pale yellowish green, mycelial felt yellowish green, (Brandrud), usually slender, bulb usually indistinct; stem olive-greenish to blue-greenish, (Moser), up to 10cm long and up to 1(2.5)cm wide, bulb not very marginate; violaceous blue to olive yellow, (Courtecuisse), 6-10cm x 0.8-1cm at top, equal or widening downward toward "rather narrow, hemispheric, marginate, subdepressed bulb" which is 1.5-2.5cm wide, "at first solid or firmly stuffed, becoming soft and spongy"; "Russian-blue" except the pallid or soon whitish base, fading and then shining, the bulb at first covered by the "straw-yellow" to "citron-yellow" remnants of the universal veil; innately fibrillose-silky, becoming bald, (Kauffman), 5-10cm x 1.2cm, blue in upper half, fading to pallid, greenish yellow cortina, sulphur yellow bulb with margin "narrow and flanged not wide and flat", (Stuntz), 5-13cm x 0.8-1.2cm, "the base bulbous sometimes only slightly; whitish or flushed greenish or violaceous; fibrous", (Phillips)

Veil:
"at bulb margin pale yellowish green" (Brandrud), universal veil "straw-yellow" to "citron-yellow", leaving remnants at first on margin of cap and on bulb of stem, (Kauffman)

Odor:
distinct, honey-like when cut (Brandrud), not distinctive (Phillips)

Taste:
slight (Phillips)

Microscopic spores:
spores 9-10.5 x 6-7 microns, elliptic, finely to distinctly and densely verrucose; gill edge more or less fertile, (Brandrud), spores 10-13 x 6.5-7.2 microns, (Moser), spores 8.5-10 x 5-6 microns, elliptic, subinequilateral, rough and subreticulate by interrupted ridges under highest magnification, (Kauffman), 9.5-11.5 x 6-6.5 microns, almond-shaped, rough, (Phillips), spores 9-12.5 x 6-7.2 microns, elliptic to pip-shaped, moderately verrucose, light yellow; basidia 4-spored, 25-30 x 9.5-12 microns, clavate, with basal clamp connection; no pleurocystidia, marginal cells 17-33 x 6-13 microns, clavate; cap cuticle of periclinal to irregularly ascending hyphae 2-8 microns wide, colorless to faintly light brown and in part somewhat encrusted, all gelatinized, septa with clamp connections, (Breitenbach)

Spore deposit:
rusty brown (Phillips)

Notes:
Kauffman(3) records Cortinarius scaurus for WA. It was found in the Olympic Mts. of WA by Smith in 1937 (Smith(22)) and 1941 (Smith(12)). Phillips(1) gives it for Pacific Northwest and NY. It occurs in BC according to Paul Kroeger (pers. comm.). Harrower(1) assigned a BC collection sequence 14 to Cortinarius scaurus and it is close to a type. Liimatainen(2) consider it to date to be known only from eastern North America and Europe in 2014. It is also found in Europe.

EDIBILITY

no (Phillips)

Synonyms and Alternate Names:
Cortinarius scaurus var. notandus Bidaud