Small agaric, growing on the ground (particularly among grass) or on litter or mulch, with a black spore print. Pileus elongate, not expanding, pale, with a darker marginal band, not viscid. Lamellae adnate. Stipe central. Partial veil remnants absent. Spores brown or black, smooth; germ pore broad. Cheilocystidia present. Lamellar trama regular. Pileipellis an epithelium. Clamp connections present.

The pileus, which does not expand but remains elongate, is a very distinctive feature that separates Panaeolopsis from Panaeolus, with which it is otherwise shares the dark spores and the pileipellis of globose or short elements. Panaeolina also occurs among grass, but the pileus expands and the spores are roughened.

Panaeolopsis Singer, Beih. Nova Hedwigia 29: 367 (1969).

One species: Panaeolopsis nirimbii.

Panaeolopsis nirimbii Watling & A.M.Young, Notes Roy. Bot. Gard. Edinburgh 41: 395 (1983).

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

Mostly among grass in parks, gardens and playing fields. Occurrence in native forest uncertain.

On the ground or among humus.

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. nirimbii]

Watling, R. & Young, T. (1983), A new species of Panaeolopsis Singer, Notes Roy. Bot. Gard. Edinburgh 41: 395–399. [Description, B&W Illustration and Microcharacters of P. nirimbii]

Young, A.M. (1989a), The Panaeoloideae (Fungi, Basidiomycetes) of Australia, Austral. Syst. Bot. 2: 75–97. [Description, Illustration and Microcharacters of P. nirimbii]

Young, T. (1997a), Panaeolopsis, in C.A. Grgurinovic, Larger Fungi of South Australia, 432–433. The Botanic Gardens of Adelaide and State Herbarium and The Flora and Fauna of South Australia Handbooks Committee, Adelaide. [Description, B&W Illustration and Microcharacters of P. nirimbii]