Collemopsis

Collemopsis is a fungal genus in the family Lichinaceae. It comprises the single species Collemopsis schaereri, a cyanolichen. Originally described in 1852 and later placed in Psorotichia, the species was shown through molecular studies to represent a distinct lineage, prompting the reinstatement of Collemopsis as a separate genus in 2024. The lichen forms dark, crustose growths on calcareous and other mineral-rich rocks that turn gelatinous when wet, with small fruiting bodies ranging from partly immersed to surface-sitting. Widespread across the Northern Hemisphere from boreal to subtropical zones, it typically inhabits well-lit rock faces that are periodically moistened and can also grow on mortar and brick.