Cladonia uncialis

Cladonia uncialis is a species of fruticose, cup lichen in the family Cladoniaceae. It was first described as a new species by Swedish taxonomist Carl Linnaeus in 1753. It was transferred to the genus Cladonia by Friedrich Heinrich Wiggers in 1780. In North America, the lichen is colloquially known as the thorn Cladonia or the thorn cup lichen.

Cladonia uncialis is host to the lichenicolous fungus species Lichenopeltella uncialicola, which is named after C. uncialis.