Malleolusa

Malleolusa is a genus of fungi within the family Sclerodermataceae. These fungi are characterized by their relatively small, typically ground-dwelling fruiting bodies. The outer layer of the fruiting body, known as the peridium, is often tough and leathery. Internally, the gleba, which contains the spores, is initially fleshy but dries out and breaks down as the mushroom matures, releasing powdery spores.

Species within the genus Malleolusa are commonly referred to as false puffballs or earthballs due to their appearance and spore dispersal mechanism, although they are structurally distinct from true puffballs (family Lycoperdaceae). The spores of Malleolusa are generally dark-colored and ornamented.

The distribution of Malleolusa species is primarily in tropical and subtropical regions, though some may extend into temperate zones. They are often found growing on the ground in forests, woodlands, or sometimes in disturbed areas. Their ecological role typically involves decomposition of organic matter, contributing to nutrient cycling in their respective ecosystems. Identification of Malleolusa species often relies on microscopic features, such as spore shape, size, and surface ornamentation, in addition to macroscopic characteristics of the fruiting body. Further research is ongoing to fully understand the diversity and ecological significance of this fungal genus.