Pluteus leoninus

Pluteus leoninus, commonly known as the lion pluteus^[1] or lion shield, can occasionally be found growing on dead wood in Europe and North Africa. The underside of the cap is typical of the genus Pluteus — the gills are pale, soon becoming pink when the spores ripen. But the upper surface is a bright tawny or olivaceous yellow. The species name leoninus (meaning leonine) refers to this cap colour.

This description is combined from several references.^[2][3][4][5]

• The golden to olive-yellow convex cap is 3–7 cm in diameter, is hygrophanous, and usually has a grooved edge. The darker central disc has a slight velvety tomentum.
• The gills are yellowish at first, then salmon pink (the colour of the spore powder).
• The stipe is up to about 7 cm, often striate, being white to cream, and often darker near the base.
• The mushroom grows on stumps and wood debris of broad-leaved trees and sometimes of conifers.
• At the microscopic level, the filamentous cap cuticle is a trichoderm. The gills have scanty bladder-shaped pleurocystidia, and abundant fusiform cheilocystidia. The spores are smooth, almost globular, approximately 7×6 μm.

Many authorities consider Pluteus fayodii to be a synonym of P. leoninus,^[6][3][7] but according to Species Fungorum, they are distinct.^[8]

According to some sources,^[9][10] it is edible but has little to no taste.

• List of Pluteus species