Peyssonnelia rosa-marina Boudouresque & Denizot, 1973

Boury-Esnault, Nicole, Bellan, Gerard, Bellan-Santini, Denise, Boudouresque, Charles-Francois, Chevaldonné, Pierre, Dias, Alrick, Faget, Daniel, Harmelin, Jean-Georges, Harmelin-Vivien, Mireille, Lejeusne, Christophe, Perez, Thierry, Vacelet, Jean & Verlaque, Marc, 2023, The Station Marine d’Endoume, Marseille: 150 years of natural history, Zootaxa 5249 (2), pp. 213-252 : 236

Peyssonnelia rosa-marina Boudouresque & Denizot, 1973 ( Fig. 9 ): an unsuspected Mediterranean rose garden

It is perhaps one of the most abundant seaweeds in the Mediterranean Sea, since it thrives from the infralittoral to the widely extended and widespread coastal detritic bottoms, in the circalittoral, where it is often dominant. It is also a particularly elegant macrophyte, resembling a calcified rosebud, hence its name, Peyssonnelia rosa-marina . Like many red algae, this seaweed can live in rather low irradiance down to ca. 100 m depth; it is an important producer of carbonate sediment and is furthermore an ecosystem engineer that takes a significant part in the construction of the coralligenous beds so characteristic of the Mediterranean. Yet, it has long been confused with its sister species, Peyssonnelia polymorpha , until the 1970s. It was then very surprising to realize that such an abundant, conspicuous, and well-characterized species, both by its morphology and anatomy, had been overlooked for so long.

Figures

FIGURE 9. Peyssonnelia rosa-marina in its habitat on the Calanques coast, Figuerolles (Provence), 13 m depth. Photo Jean- Pierre Miquel. Total length ca. 5 cm.