The species was first identified in 1958 by Japanese mycologist Tsuguo Hongo. It is known as Hikageshibiretake ("shadow numbness mushroom") in Japanese.
Description
The fruit bodies of Psilocybe subcaerulipes have caps that are 2.5 to 6 cm (1.0 to 2.4 in) in diameter, initially conic or bell-shaped but expanding to become convex, then finally somewhat flattened in maturity. A well-defined umbo (a rounded elevation resembling a nipple) is typically present. The cap color is chestnut brown when wet, but the species is hygrophanous, and when dried, changes color to become a lighter shade of brown. As is characteristic of psilocybin-containing species, P. subcaerulipes stains blue where it has been bruised or injured. The cap margins of young specimens are usually curved inwards, and have irregular, wavy edges; young specimens may also have fragments of the partial veil hanging off the margin. The whitish partial veil is similar to those of the genus Cortinarius—cobwebby, and made of silky fibrils. When the cap expands and the veil rips, the fibrils remains briefly as an annular zone on the stem, before fading into nothing.[4]
The gills have an adnate or adnexed attachment to the stem, which later becomes seceding (pulled away from the stem). The gills are a grayish-orange color initially, later turning purple-brown with whitish edges. The stem is 6 to 8 cm (2.4 to 3.1 in) long and 0.2 to 0.4 cm (0.1 to 0.2 in) thick, and has roughly the same width throughout its length, except for a widening at the base due to the whitish rhizomorphs present. Initially a whitish color, it matures to become yellowish, then brown or reddish brown. It may have white veil fragments attached to the lower two-thirds of its length, and has a pseudorhiza at the base.[1]
Microscopic features
Viewed in deposit, as with a spore print, the spores are a dark purple-brown color. Viewed microscopically, spores are roughly ellipsoid in shape, with dimensions of (5-) 6–7.5 (-8) by (3-) 4-4.5 (-5) by (3-) 3.5–4 μm. The spore-bearing cells, the basidia, are four-spored. The pleurocystidia are (11‒) 15‒20(‒32) × (3‒) 4‒6 (‒10.5) μm, hyaline, polymorphous with many forms - ventricose-capitate or broadly globose, subclavate, subfusoid to sublageniform, sometimes subcylindric or ventricose, usually a short neck but sometimes with two or three necks, occasionally irregularly branching. The cheilocystidia (cystidia located on the gill edge) are (11‒) 14‒22 (‒40) × (3‒) (4‒) 5‒7 (19) μm, and are shaped like the pleurocystidia. The pileocystidia (cystidia located on the cap surface) are hyaline, (8‒) 10‒30 (‒40) × (4‒) 5‒7 (‒10) μm and have very irregular forms - globose, subglobose, capitate or ventricose. The caulocystidia (cystidia located on the gill stipe) are (11‒) 14‒22 (‒40) × (3‒) (4‒) 5‒7 (19) μm, and are shaped like the pleurocystidia. The pileocystidia are hyaline, (13‒) 15‒38 (‒46) × 4‒8 (‒9.5) μm, polymorphous, subglageniform, clavate or fusoid.[1]
There have been several Japanese reports of intoxication following accidental consumption of this species. In a report of five cases of unintentional ingestion in Miyagi Prefecture from the period 1980–84, anxiety and panic were common to all poisoning victims, even if the anxiety was preceded by an initial period of euphoria.[8] In a later analysis of 10 cases of poisoning by this species, Musha and colleagues noted that poisoning "produced alterations of consciousness but also disturbances of consciousness such as strong drowsiness, short-term sleeping, fluctuation of vigilance and stuporous state with amnesia."[9]
The effects of P. subcaerulipes consumption on obsessive-compulsive disorder (OCD) have been tested using marble-burying behavior in mice, a commonly used animal model of OCD. When presented with an aversive stimulus such as shocks, puffs of air, or noxious food, rodents will exhibit a behavior called "defensive burying", where they will displace bedding material with their nose and forepaws; the marble-burying test takes advantage of this behavior by measuring how many glass marbles a rodent will bury under the effect of different stimuli.[10] In the experiments, when mice consumed P. subcaerulipes, it significantly inhibited their marble-burying behavior, but, unlike an equivalent dose of purified psilocybin, did not affect locomotor activity. Further, the mushroom was more effective than purified psilocybin in inhibiting the behavior, and lower doses were required. Based on these results, the authors suggest that the mushroom has the potential "to be efficient in clinical obsessive-compulsive disorder therapy".[11]
References
^ abcdGuzmán, Gastón; Cortes-Perez, Alonso; Ramirez-Guillen, Florencia (2013). "The Japanese hallucinogenic mushrooms Psilocybe and a new synonym of P. subcaerulipes with three asiatic species belong to section Zapotecorum (Higher Basidiomycetes)". International Journal of Medicinal Mushrooms. 15 (6): 607–615. doi:10.1615/intjmedmushr.v15.i6.90. PMID24266384.
^Yokoyama T. (1976). "A new hallucinogenic mushroom, Psilocybe argentipes K. Yokoyama sp. nov. from Japan". Transactions of the Mycological Society of Japan. 17: 349–54.
^Koike Y, Wada K, Kusano G, Nozoe S (1981). "Isolation of psilocybin from Psilocybe argentipes and its determination in specimens of some mushrooms". Journal of Natural Products. 44 (3): 362–65. doi:10.1021/np50015a023.
^Musha M, Kusano G, Tanaka F, Gotoh Y, Ishii A (1988). "Poisoning by the hallucinogenic mushroom Hikageshibiretake Psilocybe argentipes with special regard to the subjective experiences during psilocybin intoxication". Psychiatria et Neurologia Japonica. 90 (4): 313–33. PMID3413259.
