Yellow Club

The fruit body of Clavulinopsis helvola is cylindrical to narrowly clavate, up to 60 by 3 mm, lemon yellow to deep yellow, with an indistinct stem. Microscopically, the basidiospores are hyaline, subglobose to ellipsoid, 5 to 6.5 by 4.5 to 6 μm, with large but sparse spines up to 1.5 μm long.

The species was initially described from Europe, with a recent epitype from Slovakia. It is widely distributed throughout Europe, but has also been reported from India and Japan, China, the United States, and Brazil. The species occurs singly or in small clusters on the ground and is presumed to be saprotrophic. In America and Asia it grows in woodland, but in Europe it generally occurs in agriculturally unimproved, short-sward grassland (pastures and lawns). Such waxcap grasslands are a declining and threatened habitat, but Clavulinopsis helvola is one of the commoner species and is not currently considered of conservation concern.