Sturdy tube sponge. Hard surfaces, one of the longest tube sponge. Always seen as gray to bluish-gray in color. Commonly seen sponge on the inner reef, has a texture that looks like gray plaster.
'Callyspongia vaginalis is often mistaken for C. longissima but is distinguished by its thicker walls, shorter stout tubes and the ability to form clusters of colonies. Its surface is fibrous and bars many irregular conical projections.' (Brunt, Davies 1994)
2-4 feet.
