Trichoclasia is a genus of imperfect fungi that parasitize plants and cause systemic or local plant diseases. One of the well-known species of the Trichoclasia genus is T. spontanae. The species was first isolated in Scotland (in the city of Trondheim) at the beginning of the twentieth century, descriptions have been regularly updated since then. A new class of spore plants creates a new lectotypic form of the species T. Spon T. sporataea was initially erroneously described as T. sorediiformis, but T. Sonald also attributed this pathology to the species Trichoclada sporana