Summary:
Features include 1) small size, 2) a hygrophanous, reddish brown, subviscid to lubricous cap, 3) adnate, often mottled gills that are fuscous gray to dull buff or dark violaceous brown, with white edges, 4) a whitish or almost cap-colored stem, 5) growth on dung, in grassland, 6) a dark purple brown spore deposit, and 7) microscopic characters including angular spores. Deconica argentina is rare in the Pacific Northwest.

Gills:
broadly adnate; "fuscous gray to dull buff or dark violaceous brown, with white edges", frequently mottled

Stem:
(1.5)2-4.5(5)cm x (0.13)0.2-0.3cm, equal or eventually somewhat widened at top, hollow; whitish or almost cap-colored or more reddish brown; smooth or slightly fibrillose

Veil:
arachnoid [cobwebby] white mass when young, but stem without remains when mature

Odor:
slightly fungoid

Taste:
slightly fungoid

Microscopic spores:
spores (11)12-15(18.6) x (9)9.6-10.2(12) x 7-8.5 microns, "strongly subhexagonal or subrhomboid in face view", subelliptic in side view, light to dark yellowish brown, thick-walled, with broad truncate germ pore; basidia 4-spored, 24-32 x 10-13 microns, colorless, ventricose subpyriform, [somewhat pear-shaped and wider in middle], sometimes with a slight medial constriction; pleurocystidia absent, cheilocystidia abundant, 22-45 x 4.5-10 microns, colorless, thin-walled, "fusoid-ventricose or sublageniform to lageniform", with long neck 3-8 microns broad "and with obtuse, subglobose to globose apex"

Spore deposit:
dark violaceous brown or dark purple brown

Notes:
Deconica argentina has been found in WA, CA, MI, Mexico, Argentina, Brazil, Colombia, Venezuela, and Switzerland, (Guzman(1)). A Paul Kroeger collection from BC is deposited at the University of British Columbia (as Psilocybe).

EDIBILITY

Synonyms and Alternate Names:
Psilocybe argentina (Speg.) Singer Beih.