Grey Wall Sponge

Stelletta agulhana

The grey wall sponge is a massive sea sponge endemic to the coastal waters of Southern Africa, ranging from the Northern Cape to KwaZulu-Natal. Divers can identify this sponge by its substantial size, growing up to 10 cm thick and extending 40–50 cm in length. Its surface is covered with fine spicules, giving it a stony texture, and small oscula can be observed on its upper surface. The sponge's grey coloration helps it blend into the rocky reefs it inhabits. This species is typically found on rocky reefs at depths ranging from 2 to 90 meters. Encounters with the grey wall sponge can offer divers a chance to observe its unique texture and form.