Stereum

Stereum is a genus of fungi that includes many species commonly known as "shelf fungi" or "toothed crust fungi." These fungi are typically found growing on wood, often on dead or decaying trees. They are characterized by their leathery or corky texture and their hymenophore, which is the spore-producing surface. In many Stereum species, the hymenophore is smooth or has folds, but in some, it can be toothed, resembling the teeth of a comb.

The fruiting bodies of Stereum fungi are often sessile, meaning they lack a stalk, and grow in a shelf-like or bracket-like manner directly from the wood substrate. Their colors can vary widely, ranging from white, cream, and yellow to orange, red, and brown. Some species exhibit concentric zones of color, adding to their visual diversity. Many Stereum species are decomposers, playing an important role in the breakdown of dead wood and contributing to nutrient cycling in forest ecosystems. While some species are considered inedible due to their tough texture, others have been investigated for potential medicinal properties. Their identification often relies on a combination of macroscopic features such as shape, color, texture, and the characteristics of the hymenophore, as well as microscopic details of the spores and other fungal structures.