Psilocybe cyanofibrillosa, also known as rhododendron psilocybe and blue-haired psilocybe, is a psilocybin mushroom of the family Hymenogastraceae having psilocybin and psilocin as main active compounds. First documented in 1980 in the Pacific Northwest, it is relatively uncommon and can be distinguished from other closely related species by its smaller spores and forking cheilocystidia. Psilocybe cyanescens also has forking cheilocystidia, but less often than Psilocybe cyanofibrillosa. Psilocybe cyanofibrillosa is also distinguished from Psilocybe cyanescens by an absence of pleurocystidia. The name of this species refers to the fibrils on the Stipe (mycology) that turn bluish in age, or when handled.
This species is closely related to Psilocybe subfimetaria.
Psilocybe cyanofibrillosa has a smell and taste.
The Pileus is 1.4âÂÂ3.5 cm in diameter and conic to to broadly convex then becoming flat in age. It is not usually . The pileus is deep chestnut brown and hygrophanous, fading to yellowish brown or grayish white when dry. The surface is when moist from the separable gelatinous pellicle.
The gills are to to slightly in age. It is light grayish, becoming purplish brown with age while the edges remain whitish.
Psilocybe cyanofibrillosa spores are purplish brown in deposit, in shape, and (9)9.5âÂÂ11(12) x (5.5)6âÂÂ6.6(7) üm.
The stipe is 3âÂÂ8 cm long and 0.5 cm thick. It has an equal structure only enlarging near the base. The stipe is , pallid to yellow brown with fine fibrils that stain blue when handled. The stipe has a that sometimes leaves a fragile . White rhizomorphs are at the base. The flesh is brownish and bruises bluish to indigo-black.
Psilocybe cyanofibrillosa basidia each produce four spores, and rarely only two spores. The cheilocystidia are to and 22âÂÂ33 x 5.5âÂÂ7 üm, with an elongated, forking neck and are 1âÂÂ1.5 üm thick at its apex. Pleurocystidia are absent in Psilocybe cyanofibrillosa.
Psilocybe cyanofibrillosa is found growing scattered to gregarious, from September to December from Northern California to British Columbia, Canada. It is found in soils enriched with deciduous wood debris, among bush lupines, in Alder and Willow wood chips and bark mulch, Fir sawdust, in coastal regions, in rhododendron gardens and nurseries, and in flood plains in river estuaries.
Both psilocybin and psilocin (0.05 mg per gram dry weight and 1.4 mg per gram psilocin) were detected by Beug and Bigwood.