Pink forests of the seafloor: delicate calcareous red algae that provide protection and color to reef ecosystems through their stony structures, which harden as they accumulate calcium carbonate.

The photograph shows pinkish-red calcareous algae (most likely red algae species of the genus *Amphiroa* or *Corallina*) characterized by thin, branched, and segmented cylindrical structures. Because calcium carbonate accumulates in their cell walls, these algae possess a hard, stone-like texture. Surrounding them are delicate, net-like filamentous algae, as well as small marine crustaceans or invertebrates attached to the rock surface.