Cladoniaceae

The Cladoniaceae are a family of lichen-forming fungi in the order Lecanorales, comprising about 560 species in 18 genera. It is one of the largest families of lichen-forming fungi and is distributed worldwide, from Arctic tundra to tropical rainforests, favouring humid environments and tolerating arid conditions poorly. Notable members are reindeer moss and the cup lichens of the genus Cladonia, which has about 500 species and forms a major part of the diet of large mammals in taiga and tundra ecosystems. Many species have a dimorphic thallus, a scaly or crust-like primary form with a fruticose secondary form called a podetium or pseudopodetium. They usually grow on soil, decaying wood or tree trunks, with a few on rocks, and form symbiotic associations with green algae, usually of the genus Asterochloris. The German naturalist Jonathan Carl Zenker formally introduced the family to science in 1827.