A tropical Psilocybe cubensis isolate collected from Koh Samui island, Thailand; part of John W. Allen's Southeast Asian field survey of the early 1990s.
§ 01Morphology
Thai Koh Samui produces caramel-to-tan caps of 25–55 mm, typically smaller than continental cubensis varieties. The stipe is slim and tapering, and fruiting bodies develop to maturity more rapidly than in comparable lines.
Flushes are numerous but individually modest in specimen size; total yield per substrate is compensated by the count and frequency of flushes rather than by specimen heft. Bruising and spore colour are standard for the species.
§ 02Origin & Naming
Koh Samui — the second-largest island in the Gulf of Thailand — was among several Southeast Asian sites surveyed by John W. Allen during his ethnomycological fieldwork of the early 1990s. Allen documented and distributed multiple regional Thai isolates, of which Koh Samui is the most widely circulated.
Several Thai isolates are in contemporary circulation (Ban Hua Thanon, Thai Elephant Dung, and others) and should not be assumed to share genetic identity with Koh Samui stocks despite superficial morphological similarity.
§ 03Cultivation Temperament
Thai Koh Samui prefers warmer incubation than temperate heritage varieties, fruiting most readily at 24–28 °C. Colonisation speed is average for the species; the variety's distinguishing cultivation trait is the rapidity and frequency of flushes rather than the speed of establishment.
Yields are reliable if modest on a per-specimen basis. The variety fruits readily on CVG and standard bulk preparations; substrate tolerance is typical of the species.
§ 04Safety Profile
As with all psilocybin-containing species, Thai Koh Samui carries significant contraindications. Psilocybin is a serotonergic compound and interacts with a range of medications and mental-health conditions.
⚠ Contraindications
Not suitable for individuals with personal or family history of psychotic disorders, schizophrenia, or bipolar I; those taking SSRIs, MAOIs, or lithium; pregnant or breastfeeding persons; or those with unmanaged cardiovascular conditions. Always review the full safety codex before use.