Summary:
{See also Xeromphalina Table.} Features include 1) a dry, yellow-brown to orange-brown cap, which develops a central depression, 2) yellow to orange decurrent gills, 3) a thin, polished, tough, curved stem that is yellowish on the upper part and brown to reddish-brown on the lower part, the stem base with tawny hairs, and 4) growth on rotting conifers. The Xeromphalina campanella group is common throughout the Pacific Northwest. Molecular and mating studies by Johnson(1) and Aldrovandi(1) support the existence of a cryptic species given the new name Xeromphalina enigmatica K.W. Hughes & R.H. Petersen, closely related to Xeromphalina campanella and at present macroscopically and microscopically indistinguishable from it. Xeromphalina campanella sensu stricto occurs also in the Pacific Northwest but it appears to be a cold-tolerant species in North America - in the Pacific Northwest and northern California it was collected during winter or at higher altitudes. The implication is that the common lowland fall taxon is likely to be Xeromphalina enigmatica. "The ecological niche of X. campanella may be boreal and/or cold tolerant." (Aldrovandi(1), with Latin name italicized in the quotation).

Cap:
0.3-2.5cm across, convex becoming broadly convex with depressed center; "yellow-brown to tawny to orange-brown or cinnamon-brown"; smooth, not viscid, margin striate when moist, (Arora), 0.3-2.5cm across, convex to broadly convex, usually depressed in center when old, inrolled at first; 'dull orange "ochraceous tawny" to orange-brown "cinnamon-brown" in age, yellowish "yellow ocher" on the margin'; moist, bald, striate when fresh near margin, (Miller), 0.5-2.5cm across, flat-convex to concave, umbilicate from young stage; somewhat hygrophanous, orange-brown, umbilicus darker, margin paler to yellowish; smooth, shiny as if covered with fat, striate up to 3/4 distance to center, (Breitenbach)

Flesh:
thin, pliant; yellowish, (Arora), thin, pliant; yellowish, (Miller), thin, watery; brownish, (Breitenbach)

Gills:
decurrent, fairly well-spaced, with veins in between; yellowish to dull orange, (Arora), short decurrent to decurrent, subdistant, interveined; yellowish to dull orange, (Miller), arcuate-adnate at first, becoming deeply decurrent, (Smith), decurrent, sickle-shaped, 12-15 reaching stem, 1-3 between each pair of gills, some forked and with anastomoses; cream when young, becoming ocher-brownish; edges blunt and smooth, (Breitenbach)

Stem:
1-5cm x 0.05-0.3cm, equal or widened at base, pliant, tough, horny, usually curved; "yellowish above, brown to reddish-brown below"; smooth, often polished, base with bright tawny hairs, (Arora), 1-4(5)cm x 0.05-0.25cm, nearly equal, widening somewhat toward base, horny, cartilaginous, curved; yellowish just at apex, reddish brown in lower part, ending in a basal bulb that is covered with strigose tawny hairs, (Miller), 1.5-3cm x 0.1-0.15cm, equal or wider at top, base sometimes slightly bulbous, stem cartilaginous, hollow, often bent; orange-cream at top, red-brown in lower part, to dark brown at base; finely dark-pubescent, base with orange tomentum, (Breitenbach)

Odor:
insignificant (Breitenbach), may have faint odor of household geranium, may have carrot odor, (Redhead), not distinctive (Smith), not distinctive (Miller)

Taste:
mild, somewhat mushroomy, (Breitenbach), not distinctive (Miller)

Microscopic spores:
spores 5-8 x 3-4 microns, elliptic, smooth, amyloid, (Arora), spores 5.8-7.8 x 3.1-3.4 microns, cylindric to elliptic, (Redhead), spores 5-7(9.5) x 3.0-3.5(4.0) microns, elliptic, amyloid (blue) with light yellowish contents in Melzer''s reagent, thin-walled; basidia 4-spored, 17-28 x 3.5-5.5 microns, clavate, thin-walled, colorless in KOH, yellow in Melzer''s reagent; pleurocystidia "the same as cheilocystidia but infrequently found, usually near gill edge", cheilocystidia protruding 1/3 to 1/2 of total length beyond hymenium, 29-55 x 6.0-13.5 microns, "fusoid, ventricose, subventricose, narrowly fusiform to clavate", colorless in KOH and in Melzer''s reagent, thin-walled, usually numerous; gill trama of irregular to loosely interwoven hyphae 2.5-10 microns wide, yellow-brown to light yellowish near apex in KOH, with thickened walls (0.9-1.7 microns thick); cap trama of erect hyphae 4.2-21.0 microns wide, walls thickened (0.5-1.0 microns), yellow-brown with incrustations on the walls in KOH, red-brown in Melzer''s reagent; cap cuticle composed of occasional pileocystidia 33-50 x 10-15 microns, narrowly clavate, clavate to fusiform, colorless to yellow-brown in KOH, embedded in the cap trama; stem cuticle of hyphae 3-15 microns wide, thick-walled (1-1.5 microns thick), with little pigment, usually light yellowish in KOH, caulocystidia 25-40(75) x (8.5)11-15 microns, clavate, subventricose, fusiform, colorless, thin-walled, often with clamp connection at base, protruding 1/3 of length, single or in small fascicles, (Miller), spores 5.6-7.4 x 3-3.3 microns; elliptic to cylindric-elliptic, smooth, colorless; basidia 4-spored, clavate, 19-25 x 5-6 microns, narrowly clavate, with basal clamp connection; pleurocystidia none, cheilocystidia 35-55 x 9-15 microns, clavate to ventricose; cap cuticle of +/- irregular hyphae 3-20 microns wide, with epimembranal brownish pigments, septa with clamp connections; caulocystidia 30-70 x 10-25 microns, clavate to fusiform-ventricose, (Breitenbach)

Spore deposit:
white to pale buff (Arora), ''yellow "light buff"'', (Miller), cream-whitish (Breitenbach)

Notes:
Collections of Xeromphalina enigmatica include 9 from WA, 5 from BC, and 5 from ID, as well as others from NL, QC, CA, FL, MS, NC, NY, TN, Mexico, Finland, Germany, Russia, Spain, Japan, and China. (Aldrovandi(1)). Two of the collections used were from Pacific Spirit Park in BC and two from Capilano River Park in BC (Shannon Berch, pers. comm.). Xeromphalina campanella sensu stricto collections were from BC (3 collections), WA (8 collections), ID (1 collection), NB, AK, CA, TN, UT, VA, Czech Republic, Finland, France, Germany, Sweden, and Russia. Collections were examined as Xeromphalina campanella from BC, WA, OR, ID, AB, MB, NB, NL, NS, NT, ON, QC, YT, AK, CA, CO, CT, DC, FL, IN, MA, MD, ME, MI, MN, MT, NC, NH, NJ, NM, NY, PA, TN, TX, UT, VA, VT, WY, United Kingdom (England), Poland, Sweden, Switzerland, USSR, and Algeria, (Redhead(2)). It was reported (as X. campanella) also from Mexico (Laferriere(1)).

EDIBILITY

no (Phillips)