Gaillona rosea is a species of red algae in the order Ceramiales. The species was previously classified under several genera, including Callithamnion as Callithamnion roseum.
Gaillona rosea is a delicate, filamentous red alga that forms fine, branched structures. It typically grows attached to substrates such as rocks, shells, or other algae.
Gaillona rosea is found in marine environments across Europe, islands of the Atlantic Ocean, the western Atlantic, and parts of Africa.
The species was originally described as Ceramium roseum by Roth in 1798. It has since been placed in several genera, including Conferva, Callithamnion, and Aglaothamnion, before being reassigned to the genus Gaillona by Athanasiadis in 2016.