Panaeolus papilionaceus, also known as Agaricus calosus, Panaeolus campanulatus, Panaeolus retirugis,[1] and Panaeolus sphinctrinus,[1] and commonly known as Petticoat mottlegill, is a very common and widely distributed little brown mushroom that feeds on dung.
Cap: 1–5 cm across, obtusely conic, grayish brown,[1] not hygrophanous, becoming campanulate in age, margin adorned with white toothlike partial veil fragments when young or towards the edge,[1] flesh thin.
Gills: adnate to adnexed close to crowded, one or two tiers of intermediate gills, pale gray, acquiring a mottled, blackish appearance in age, with whitish edges.
Spores: 12–18 x 7–10 μm, elliptical, smooth, with an apical pore, spore print black.
Stipe: 6–12 cm by 2–4 mm, gray-brown to reddish brown, darker where handled, paler toward the apex, brittle,[1] fibrous, and pruinose.
Odor: Mild.
Taste: Unappetizing.
Microscopic features: Basidia 4-sterigmate; abruptly clavate. Cheilocystidia abundant; subcylindric, often subcapitate or capitate.
Panaeolus papilionaceus is inedible,[4] and is neither choice in flavor nor substantial in mass. While similar looking species, such as Psilocybe mexicana, do contain psilocybin, Panaeolus papilionaceus does not.[5]
^Phillips, Roger (2010). Mushrooms and Other Fungi of North America. Buffalo, NY: Firefly Books. p. 236. ISBN978-1-55407-651-2.
^Allen, John W. (2013). Ethnomycological Journals: Sacred Mushroom Studies Volume IX. Santa Cruz, California and Seattle, Washington, respectively: MAPS and Exotic Furays. pp. 130–175. ISBN978-158-214-396-5.