The Families of Mushrooms and Toadstools Represented in the British Isles


L. Watson and M. J. Dallwitz


‘Oyster Mushrooms’.


Anamorphic forms occurring (represented by 20 species of Antromycopsis, mainly on wood).

Morphology. The fruit-bodies producing basidia and basidiospores; persistent; usually clustered; differentiated into a stipe and pileus with the hymenium underneath the latter (then the stipe very excentric, e.g. Pleurotus dryinus), or attached laterally and bracket-shaped (or at least with the stipe short and lateral, e.g., P. ostreatus); medium sized to large; in Pleurotus, 3–15 cm across. The mature pileus convex, or more or less flat or somewhat depressed. The top of the pileus white or whitish, or buff and grey, or purplish brown, or light brown, or dark brown, or blackish. The stipe bearing a ring but no volva, or with neither ring nor volva. The hymenium borne on gills. The gills conventional, not obviously suggestive of modified pores or cupules. The basidia ‘unmodified’. The basidiospores cylindrical; hyaline, or white.

The hyphal walls lamellate, with a thin, electron-dense outer layer and a relatively thick, electron-transparent inner layer. The hyphae monomitic, or dimitic. The generative hyphae not inflated.

Ecology. Parasitic and saprophytic; on vascular plants. The fruit-bodies on dead wood and on living wood. Associated with broad-leaved trees and with conifers. The fruit-bodies on trunks and branches of living trees and on dead trees and fallen logs. On trunks of broad-leaved and coniferous trees, with P. ostreatus especially damaging to beech. Found in broad-leaved woodland and in mixed woodland.

British representation. Hohenbuehelia, Pleurotus.

World representation. 54 species; genera 2. “Widespread”.

Classification. Basidiomycota; Basidiomycetes; Agaricomycetidae; Agaricales.

Comments. Some species supposedly edible (e.g., young Pleurotus ostreatus), or poisonous (with at least some species having markely emetic properties). Including some anamorphic forms.

Illustrations. • Pleurotus dryinus, Pleurotus ostreatus (LH). • Pleurotus ostreatus (Price).

To view the illustrations with captions giving names in current use, go to the interactive key. This also offers full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, source references, and other relevant material.

Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2008 onwards. The families of mushrooms and toadstools represented in the British Isles. Version: 6th March 2015.’.