This species can present itself with thalli that grow up until 25 cm. It's usually of a brown-dark green color, sometimes close to black.

Constituted by axes attached to a common basal disc, it's divided in a pseudo-dichotomous form and has rigid consistency; the axes have, a little above from the basal disc, whorls of tiny tortile branches (observable by magnifying glass) which keep getting closer to each other, as we go up the thallus, until it assembles in a continuous and spongy coating. 

This species can usually be found in small tide puddles surrounded by sand, in central and calm coastline regions.