Psilocybe Semilanceata - Similar Species

Similar Species

There are several other Psilocybe species that may be confused with P. semilanceata due to similarities in physical appearance. P. strictipes is a slender grassland species that is differentiated macroscopically from P. semilanceata by the lack of a prominent papilla. P. mexicana, commonly known as the "Mexican liberty cap", is also similar in appearance, but is found in manure-rich soil in subtropical grasslands in Mexico. It has somewhat smaller spores than P. semilanceata, typically 8–9.9 by 5.5–7.7 μm. Another lookalike species is P. samuiensis, found in Thailand, where it grows in well-manured clay-like soils or among rice paddies. This mushroom can be distinguished from P. semilanceata by its smaller cap, up to 1.5 cm (0.6 in) in diameter, and its rhomboid-shaped spores. P. pelliculosa is physically similar to such a degree that it may be indistinguishable in the field. It differs from P. semilanceata by virtue of its smaller spores, measuring 9–13 by 5–7 μm.

The toxic species Cortinarius rubellus (formerly known as C. orellanoides) has been confused with P. semilanceata by novice collectors looking to consume the mushrooms for hallucinogenic effects, sometimes with drastic consequences. The expanded and bluntly umbonate cap of C. rubellus is orange-brown with a larger diameter than P. semilanceata, typically ranging from 2–6 cm (0.8–2.4 in). The gills are adnate to sinuate in attachment to the stem, and cinnamon-brown in color (rather than dark gray to purple-brown). Its stem is roughly the same color as the cap, 5–8 cm (2.0–3.1 in) long and much thicker than P. semilanceata—usually 0.6–1 cm (0.2–0.4 in), and sometimes bears lemon-yellow bands. It is a mycorrhizal species that grows on acidic soil among mosses, usually in wet coniferous forests. P. semilanceata has also been confused with the toxic muscarine-containing species Inocybe geophylla, a whitish mushroom with a silky cap, yellowish-brown to pale grayish gills, and a dull yellowish-brown spore print.