Description: Massive-lobose, often having the form of a flattened hemisphere, composed of a network of anastomosing plates and ridges, with the orange crests showing through but the interstices usually being filled with silt. The whole sponge may approximate the form, appearance and size of a human brain. At lateral growth areas repent and compact coalescing branches can occur. In places, tangled masses of these branches can themselves form the body of the sponge. Attachment to the substrate may be discontinuous. Size up to 10cm thick by 30cm in diameter, but smaller "fist-sized" specimens are more typical. Bright to buff orange; yellow (butter colour). "Yellow-orange in the basal regions, becoming more brown in top". Eventually turns grey in alcohol. Compact, firm. Oscules are borne at the ends of the papillae and are clearly visible under water. The papillae collapse on collection and the oscules are then no longer apparent.

Distribution: Known in the British Isles only on the Channel coast -in the Fleet (Dorset), Poole Harbour (Dorset), and Southampton Water (Hampshire). Also known from the River Morlaix in Brittany, and from the Mediterranean.

Distribution Map from NBN: Suberites massa at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Suberites massa at iNaturalist World Species Observations database.