Summary:
{See also Xeromphalina Table.} Features include 1) a dry reddish-brown to ochraceous-tawny cap that fades to yellowish, and often has a central depression, 2) short decurrent yellow to yellow ocher gills, 3) a tough stem that is tawny or yellowish on the upper part and dark brown on the lower part, the base of the stem with tawny mycelium, 4) a bitter taste, 5) growth on conifer needles and debris, 6) a white spore deposit, and 7) microscopic characters. The microscopic characters include relatively small spores, a relatively smooth, non-incrusted cap cuticle hyphae embedded in a gel layer 1-3 hyphae deep in immature fruitbodies, and colorless pileocystidia around the cap margin, (Redhead(2) for both subspecies). Redhead(2) says that Xeromphalina cauticinalis sensu A.H. Sm.(1953) is mainly Xeromphalina cornui, and moreover that Xeromphalina cauticinalis var. cauticinalis sensu O.K. Miller (1968) is mainly Xeromphalina cornui and that Xeromphalina cauticinalis var. acida O.K. Miller is Xeromphalina parvibulbosa (Kauffman & A.H. Sm.) Redhead. The Redhead(2) description abstracted here is for ssp. cauticinalis.

Cap:
1-2cm across, convex with incurved margin, becoming flat-convex to flat and centrally depressed with recurved margin; ochreous with fulvous disc and amber to pale luteous [pale yellow] edges; moist, margin obscurely translucent-striate, (Redhead), 0.5-2.5cm across, convex becoming flat or with small central depression, reddish brown "to tawny or ochraceous-tawny, fading to yellowish"; smooth, not viscid, (Arora)

Flesh:
colored as cap (Redhead), very thin, pliant, (Arora)

Gills:
short decurrent, moderately spaced, 2-3 tiers of subgills; pale luteous to yellowish ochreous, (Redhead), adnate to decurrent, interveined; yellow, (Arora)

Stem:
2.5-7.2cm x 0.06-0.1cm, "strict except for the base, horny, stuffed"; ochreous to luteous at top, dark brick to chestnut in lower part, with ochreous to fulvous base; tomentose, powdered at top with ochreous-colored cystidia, (Redhead), 2-8cm x 0.1-0.25cm, equal or more often with small bulb at base, pliant, tough; tawny or yellowish in upper part, dark brown in lower part; base with tawny mycelium, (Arora)

Veil:
none (Arora)

Odor:
not distinctive (Redhead)

Taste:
immediately to tardily bitter (Redhead), mild (Arora)

Microscopic spores:
spores 4.8-6.8 x 3-3.5 microns, elliptic to broadly oval, smooth, amyloid, colorless, thin-walled; basidia 4-spored, 22-25 x 4.8-5 microns, narrowly clavate, with clamp connections; cheilocystidia "usually conspicuous, abundant", 29-39 x 6-8 microns, fusoid to clavate, usually undulate [wavy], with 1-3 irregular finger-like processes at top; cap trama duplex, "the subpellis composed of swollen, orangish to reddish brown or yellowish (in KOH) hyphae" (2)2-22(40) microns wide, "with smooth to tardily incrusted, slightly thickened walls", subtended by a layer of finely to moderately incrusted, more filamentous hyphae 3-7 microns wide, "yellowish to orangish or reddish in KOH (depending upon age and geographic location)"; cap cuticle a thin layer of repent, smooth, filamentous hyphae 3-4 microns wide, "embedded in a thin ephemeral gelatinous layer", giving rise to circumcystidia [cystidia around the margin] or cystidioform ends; pileocystidia around cap margin "initially filamentous, although in older specimens they can swell considerably", thin-walled, sometimes refringent, colorless, smooth, with a few obtuse diverticula at top, 22-55 x 3-4 (expanding to 8) microns; stem cuticle hyphae 3-4 microns wide, colorless in apical region, reddish brown in lower stem with roughened thickened walls, "bearing dense clusters of caulocystidia apically and scattered or clustered cystidia and hairs below"; caulocystidia 45-55 x 5-6 microns, "filamentous, substrangulate to subfusoid or occasionally lobed or forked", thick-walled, (Redhead), spores 5.5-7 x 3-4 microns, elliptic, smooth, amyloid, (Arora)

Spore deposit:
white (Arora)

Notes:
Collections were examined from BC, WA, OR, ID, AK, CA, CO, MT, NM, WY, Finland, France, Sweden, Switzerland, United Kingdom (England), and USSR, (ssp. cauticinalis), and ON, QC, AL, FL, MD, MI, TN, Finland, Sweden, and Japan, (ssp. pubescentipes), (Redhead(2)).

EDIBILITY

unknown (Arora)

Synonyms and Alternate Names:
Marasmius cauticinalis "Fr., Xeromphalina fulvobulbillosa (R.E. Fr.) Maire"