Name: Leratiomyces ceres
Author: (Cooke & Massee) Spooner & Bridge
Citation: Mycotaxon 103: 109-121 (2008)
Deprecated Synonyms: Stropharia aurantiaca (Cooke) M. Imai, Hypholoma aurantiacum (Cooke) Faus, Leratiomyces aurantiaca, Psilocybe ceres (Cooke & Massee) Sacc., Nematoloma aurantiacum (Cooke) Guzmán, Stropholoma aurantiacum (Cooke) Balletto, Psilocybe aurantiaca (Cooke) Noordel., Stropharia aurantiaca sensu Taylor, Hypholoma aurantiacum sensu Moncalvo
The cited Mycotaxon article is titled “Taxonomy of the fungus commonly known as Stropharia aurantiaca, with new combinations in Leratiomyces”. The paper clearly demonstrates the close relationship between “the fungus commonly known as Stropharia aurantiaca” and the type for Leratiomyces. The equivalence of this species with the species Psilocybe ceres is a bit less satisfying, but seems reasonable. The challenge there is “The holotype collection comprises sectioned, rather fragmentary fruitbodies not suitable for DNA study.” They also couldn’t find any cheilocystidia, but again the implication is that this is the result of the condition of the type.
Cap: 2-6 cm; convex, becoming broadly convex, broadly bell-shaped, or nearly flat; sticky when fresh, but soon dry; scarlet to reddish orange or reddish brown; smooth; when young adorned with white partial veil remnants.
Gills: Attached to the stem, often by a notch; close; pale yellow at first, later purplish gray to purple-black; with whitish to pale yellow edges when mature.
Stem: 3-7 cm long; up to 1 cm thick; dry; with or without a ring zone; fairly smooth or finely hairy; whitish to yellowish, staining reddish orange with maturity; base often with whitish to yellowish mycelial threads.
Odor and Taste: Not distinctive.
Spore Print: Dark purple-brown to purple-gray.
Chemical Reactions: KOH on cap surface dark gray.
Microscopic Features: Spores 9-14 × 5.5-9 µ; smooth; elliptical; with a germ pore; brown in KOH. Chrysocystidia present on edges and faces of gills; scattered to abundant; to about 50 × 15 µ; clavate to mucronate; thin-walled; contents hyaline to yellow in KOH. Cheilocystidia to about 60 × 10 µ; cylindric to fusoid; sometimes capitate. Pileipellis a thin ixocutis of cylindric elements over a nearly cellular subpellis.