Fissellia

Fissellia is a genus of fungi belonging to the family Physalacriaceae. These fungi are commonly known as bonnet mushrooms due to the distinctive shape of their caps. The genus was first described by French mycologist Lucien Quélet in 1886. Fissellia species are saprobic, meaning they obtain nutrients from dead organic matter, and are typically found growing on decaying wood, leaf litter, or soil.

The fruiting bodies of Fissellia mushrooms generally feature a convex to campanulate cap that can range in color from white to brown, often with a slightly sticky or slimy surface. The gills are typically adnate or decurrent, and can be white or cream-colored. The stipe, or stem, is usually slender and can be smooth or slightly fibrillose. Many Fissellia species are small and delicate, making them less conspicuous than some other mushroom types.

Distribution of Fissellia is widespread, with various species found across temperate regions of the Northern and Southern Hemispheres. Identification of specific Fissellia species can sometimes be challenging due to their morphological similarities and the subtle differences that distinguish them. Microscopic features, such as spore shape and size, are often crucial for accurate classification. While some Fissellia species are of interest to mycologists for their ecological roles, few are considered to be of significant culinary or medicinal importance. Research into the genus continues to expand our understanding of fungal diversity and the ecological interactions of these small woodland fungi.