Psilocybe mexicana is a psychedelic mushroom. Its first known usage was by the natives of North and Central America over 2,000 years ago. Known to the Aztecs as teotlnanácatl, from the Nahuatl teotl ("god") + nanácatl ("fungus"). This species was categorized by French botanist Roger Heim.

Psilocybin mushrooms, commonly known as magic mushrooms or shrooms, are a polyphyletic informal group of fungi that contain psilocybin, which turns into psilocin upon ingestion. Biological genera containing psilocybin mushrooms include Psilocybe, Panaeolus, Inocybe, Pluteus, Gymnopilus, and Pholiotina.