What Psilocybe cubensis looks like and where it grows

The specimen label

Sources for the table: the morphological description by Singer and Smith as summarised in a 2025 review in the Journal of Fungi (Kurzbaum et al., 2025), and the species summary on Wikipedia for stem length and spore size. Published measurements differ a little between authors, as they do for most fungi: cultivated and wild material, young and old mushrooms, and fresh and dried specimens are not the same.

Cap and gills

Young caps are rounded to conical and often carry a small raised point in the centre. As the mushroom matures, the cap opens out and flattens, and the colour fades from a darker brown centre to paler margins. The gills start pale grey and deepen to sepia and darker as the spores ripen, so mature specimens look dark underneath.

The ring and the spore print

The partial veil covers the gills of a young mushroom and tears as the cap expands, leaving a white ring on the upper stem. To take a spore print, a cap is placed gill side down on paper for several hours. In P. cubensis the print is dark purple-black; spore colour is one of the standard features mycologists use to tell dark-spored genera such as Psilocybe apart from brown- or rust-spored ones.

Why it turns blue

Damaged tissue turns blue quickly. Researchers at the Hans Knöll Institute in Jena identified the cause in P. cubensis in 2019: two enzymes act in sequence. A phosphatase called PsiP converts psilocybin to psilocin, and a second enzyme, PsiL, oxidises psilocin so that it links into chains of three to thirteen units. Those chains are the blue pigment (Lenz et al., 2020).

Habitat

P. cubensis is coprophilous: it grows on the dung of herbivores. The usual substrates are cow dung, occasionally horse dung, sugar cane mulch and rich pasture soil; in Asia it is also found on water buffalo dung. The review cited above describes humid subtropical areas, river valleys in particular, as typical habitat. In the northern hemisphere fruiting is reported from February to December, in the southern hemisphere from November to April.

The relationship with grazing animals runs deep. Its closest known wild relative, Psilocybe ochraceocentrata from sub-Saharan Africa, also grows on the dung of large herbivores (Bradshaw et al., 2026). More on that in name and origin.

Where it has been recorded

The Global Biodiversity Information Facility held 3,931 occurrence records of P. cubensis on 10 October 2026 (GBIF occurrence search). The countries with the most records:

Records also come from the Caribbean, Central America, India, Thailand, Vietnam and South Africa, among others. These numbers show where people photograph and log the mushroom; they are not a measure of how common it is. In the United States the species is reported from the Gulf Coast and south-eastern states. GBIF does not separate wild from cultivated material, so records from cooler countries, such as the 13 from the United Kingdom, may well come from indoor cultivation.

The Australian population is a well studied case. Genome data show it was introduced at some point and has since become naturalised, with more genetic variation than the cultivated lines (McTaggart et al., 2023).

A word on picking

A description and a table are not enough to identify a wild mushroom safely. Several genera grow in the same pastures, some brown mushrooms with dark spores are hard to separate without a microscope, and picking or possessing psilocybin mushrooms is illegal in most countries. This page describes the species; it is not an identification guide for foraging. The legal position by country is set out in legal status.