Desmarestia. Thalle glauni, cylindreique, comprime, rameaux dresses sur un plan, converts de ramuscules formant aiguillons, tube axial creux a grosses cellutes et perpendiculaires a l'axe, des chapelets de cellules rayonnants vers la peripherie
This alga has a high concentration of sulphuric acid and malic acid; the acids may deter grazers. Also, they discolor the pigments in other algae if they are placed in the same container.. Photographed at 12 m depth.
