Willeya is a genus of saxicolous (rock-dwelling), crustose lichens in the family Verrucariaceae.

[1] Most species are found in southeast Asia, although individual representatives are known from Australia, Europe, and North America.

Willeya was originally proposed by Swiss lichenologist Johannes Müller Argoviensis in 1883 to contain Staurothele species with pale ascospores, and based on Willeya diffractella as the type species.

This lichen, found in a botanical garden in the Netherlands, was growing on limestone that was imported from China.

Their perithecia have algae cells in the hymenium, a feature shared with only a few Verrucariaceae genera (Endocarpon is another).