Description
The smooth surface of this sponge often shows long trail or finger like processes, giving it an irregular appearance. Young specimens do not show these processes and can easily be confused with H. panicea. The in- and ex-current openings are hard to recognize. Can usually be found on hard substrata such as rocks and shells. Above water it gives a faint carbide scent.

Size
Surface 50 mm thick and up to 200 mm in diameter, with processes of 120 mm length.

Colour
Light yellow to brownish yellow.

Habitat
From the shallow coastal waters to a depth of 60 metres, on hard substrata.

Distribution
Common in the Oosterschelde, more rare in the Grevelingen.