Small to large agaric, growing on the ground, litter, mulch or dung (rarely on very rotted wood), with a black or rarely purple-brown spore print. Pileus white, pale, brown, grey or black, not or rarely viscid or glutinous. Lamellae adnexed or adnate. Stipe central. Partial veil remnants absent or rarely a membranous annulus. Spores brown, grey or black, smooth or rarely very finely ornamented; germ pore broad. Cheilocystidia present. Chrysocystidia present or absent. Lamellar trama regular. Pileipellis a hymeniderm or an epithelium; sometimes with pileocystidia. Clamp connections present, rarely absent.

The genus Psathyrella is similar, sharing the black spore print and the pileipellis composed of globose or short elements. However, Psathyrella rarely occurs on dung, and it differs in the rather fragile texture of the fruit-body. Furthermore, chrysocystidia are never present, and spores become paler in concentrated sulphuric acid (a test only to be undertaken while following appropriate safety procedures). Other agarics producing a black spore print include Coprinellus (usually deliquescent), Coprinopsis (always deliquescent), Lacrymaria (with coarsely fibrillose pileus surface and very rough spores) and Stropharia (with a pileipellis that is a cutis or, rarely, a trichoderm). Some species of Psilocybe grow on dung , but the spore print is dark brown or purple-brown (not black), the pileipellis is a cutis, composed of cylindrical, gelatinised hyphae, and chrysocystidia are absent. Panaeolina is similar in appearance, but it has a dark brown rather than black spore print, grows in lawns (not on dung) and has rough spores, whereas in Panaeolus only P. olivaceus has ornamented spores (which are very finely ornamented). Panaeolus cyanescens is keyed out separately because it is distinctive in having a blue-staining fruit-body and the presence of metuloid (thick-walled) cystidia.

Eleven species in three subgenera:

Subgenus Panaeolus (pileus mostly dry, hygrophanous or not, not blueing, annulus absent): P. acuminatus (= P. rickenii), P. bernicis, P. cinctulus (= P. subbalteatus), P. fimicola (= P. ater), P. olivaceus (with very finely ornamented spores), P. paludosus, P. papilionaceus (= P. retirugis, P. sphinctrinus and P. campanulatus in the sense of many authors) with var. papilionaceus and var. parvisporus, P. reticulatus.

Subgenus Anellaria (fruit-bodies robust, pileus viscid, not hygrophanous, annulus present or absent): P. antillarum and P. semiovatus (= Anellaria) with var. semiovatus and var. phalaenarum.

Subgenus Copelandia (fruit-body blueing, thick-walled cystidia present): P. cyanescens. This species is keyed out separately due to the very distinctive combination of blueing fruit-bodies and the presence of thick-walled cystidia.

W.A., S.A., Qld, N.S.W., Vic. and Tas. (and probably also N.T.).

In native forests and in plantations, pastures, parks and gardens.

On dung or manured soil, or on the ground, rarely on rotted wood.

Saprotrophic.

Bougher, N.L. (2009a), Fungi of the Perth region and beyond: a self-managed field book, Western Australian Naturalists' Club (Inc.), Perth. [Description and Illustration of P. fimicola and P. papilionaceus]

Bougher, N.L. & Syme, K. (1998), Fungi of Southern Australia. University of Western Australia Press, Nedlands. [Description, Illustration and Microcharacters of P. papilionaceus (as P. campanulatus)]

Breitenbach, J. & Kranzlin, F. (eds) (1995), Fungi of Swizerland. Volume 4. Agarics 2nd part. Edition Mykologia, Lucerne. [Description, Illustration and Microcharacters of P. fimicola and P. papilionaceus and seven other species from Europe]

Fuhrer, B. (2005), A Field Guide to Australian Fungi. Bloomings Books, Hawthorn. [Description and Illustration of P. papilionaceus (under this name and also as P. sphinctrinus)]

Gerhardt, E. (1996), Taxonomische Revision der Gattungen Panaeolus und Panaeolina (Fungi, Agaricales, Coprinaceae), Bibliotheca Botanica, Heft 147, E. Schweizetbart'sche Verlagsbuchhandlung, Stuttgart. [Description, B&W Illustration and Microcharacters of P. acuminatus, P. antillarum, P. cinctulus, P. fimicola, P. olivaceus, P. papilionaceus var. papilionaceus and var. parvisporus, P. reticulatus, P. semiovatus var. semiovatus and var. phalaenarum and Description and Microcharacters of P. bernicis and P. paludosus]

McCann, I.R. (2003), Australian Fungi Illustrated. Macdown Productions, Vermont. [Illustration of P. acuminatus (as P. rickenii) and P. papilionaceus (as P. sphinctrinus)]

Watling, R. & Gregory, N. (1987), British Fungus Flora. Agarics and Boleti. 5 / Strophariaceae & Coprinaceae p.p. Hypholoma, Melanotus, Psilocybe, Stropharia, Lacrymaria & Panaeolus. Royal Botanic Garden, Edinburgh. [Description and Microcharacters of P. acuminatus (as P. rickenii), P. antillarum, P. fimicola, P. papilionaceus (as P. sphinctrinus) and P. semiovatus, and B&W Illustration of P. acuminatus (as P. rickenii), P. papilionaceus (as P. sphinctrinus and P. campanulatus sensu auct.) and P. semiovatus]

Young, A.M. (1989a), The Panaeoloideae (Fungi, Basidiomycetes) of Australia, Austral. Syst. Bot. 2: 75–97. [Description and Microcharacters of P. acuminatus (as P. rickenii), P. antillarum, P. bernicis, P. fimicola (and as P. ater), P. paludosus and P. papilionaceus (as P. sphinctrinus) and B&W Illustration of P. acuminatus (as P. rickenii), P. antillarum, P. bernicis, P. fimicola and P. papilionaceus (as P. sphinctrinus)]

Young, T. (1997b), Panaeolina, Panaeolus and Copelandia, in C.A. Grgurinovic, Larger Fungi of South Australia, 482–489. The Botanic Gardens of Adelaide and State Herbarium and The Flora and Fauna of South Australia Handbooks Committee, Adelaide. [Description and Microcharacters of P. acuminatus (as P. rickenii), P. antillarum, P. fimicola, P. paludosus and P. papilionaceus (as P. sphinctrinus), and Illustration of P. antillarum and P. papilionaceus (as P. sphinctrinus)]

Young, A.M. (2005b), A Field Guide to the Fungi of Australia. University of New South Wales Press, Sydney. [Description and Illustration of P. papilionaceus, and Description and B&W Illustration of P. antillarum]