Pyrenocollema is a genus of lichenized fungi in the biological division Ascomycota. The genus was described by German botanist Johannes Reinke in 1895 and has been placed in the family Xanthopyreniaceae. Species in the genus form borderline lichen symbioses with cyanobacteria and are typically found in marine and freshwater environments, growing on rock surfaces or within calcareous substrates such as limestone and the shells of barnacles and limpets. Several species formerly placed in Pyrenocollema have been transferred to the related genus Collemopsidium.

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