This distinctive compound ascidian can be found on jetty pylons and rocky reef in almost any colour, including yellow, red, white, brown, purple or orange. It is most easily recognised by its growth form, where the lobes, attached to the substrate by a basal stem, curl around on themselves, until the largest colonies resemble a brain. Zooids are located in straight rows along the face of the lobes on both sides, each row terminating at the colony edge with a large cloacal aperture. This species is unlikely to be mistaken for another, except maybe the youngest of colonies, where the lobe has yet to start to curl and is fan-shaped.
