Clauzadea is a genus of lichen-forming fungi in the family Lecideaceae. The genus contains four species. These lichens grow almost exclusively on limestone and other calcium-rich rocks, often living mostly hidden within the upper layers of the stone with only a faint grey or brown film visible on the surface. They produce small, initially reddish-brown fruiting bodies that darken to black and may sit flush with the rock surface or be sunken so deeply that they leave neat pits when they weather away.

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