Psilocybe ruiliensis

Psilocybe ruiliensis is a species of psilocybin mushroom in the family Hymenogastraceae. Described as new to science in 2016, it is found in Yunnan province of southwest China. The species epithet, 'ruiliensis', is a reference to the location Ruili where the type collections were found. The type specimens were growing solitary to scattered in grasslands in which cows and horses had previously grazed.

Description

 * Cap: 10–20 mm in diameter; conic to almost plane, with or without umbo or small acutely papillate at the disk; brownish-yellow (often with reddish tinge); hygrophanous and translucently striate when moist, watery brown when wet; sometimes bruising blue when damaged or mature; cortinate white veil and sometimes small scales when young.
 * Gills: Yellowish or beige when young, chocolate brown in age (gray-purple or purple tinge), with adnate to subsinuate or adnexed attachment; edges serrulate and slightly wavy.
 * Spores: Brown with purple tinge (in water); ellipsoid to subhexagonal; smooth and slightly thick-walled, sometimes containing 1–2 oil drops; 9–11 by 6–7.5 μm.
 * Stipe: 27–62 mm long, 1.5–3.5 mm thick; yellow-white to brownish, sometimes bruising bluish when damaged; central or occasionally slightly eccentric; fibrillose; hollow; annulus absent; equal to slightly enlarged bulbous base. Stem base with rhizomorphic white mycelium.
 * Odor: Slightly grassy.
 * Microscopic features: Larger hexagonal and subrhomboid basidiospores (9.6–12.0 by 6.4–8.4 μm); ventricose-lageniform cheilocystidia and pleurocystidia.