Endocarpon riparium

About

Endocarpon riparium is a species of corticolous (bark-dwelling) squamulose lichen in the family Verrucariaceae. This lichen was discovered growing near rivers in the Brazilian Amazon, where it forms patches on wood, tree bark, and rocks that are sometimes underwater. It reproduces by producing small detachable pieces along its edges rather than through typical spore-bearing structures, making it unusual among related species.

Summary from Wikipedia