A low lying plant which forms dense, irregularly lobed cushions 2-3 cm thick and up to 20 cm or more across, the surface is firm and corrugated with a velvety or spongy texture . The holdfast is a spongy mass of tissues. Colour is dark green and the surface is slippery.

They are found on intertidal rocks on open coasts in moderate shelter.

Uses the sun's energy

New Zealand Seaweeds: An Illustrated guide. Nelson