Saltcorner
By Bob Goemans
By Bob Goemans
Likely Reef Tank Suitable
Likely Fish-Only Tank Suitable
Generally called "Peanut Worms" these non-segmented worms in the Phylum Sipunculida consist of about 300 species, and are somewhat U-shaped or sausage-shaped. Their body is usually covered with bumps, small spines, warts, or tubercules, which provide some protection from larger predators. Some bore into calcareous rock, while others burrow into sand or mud. The mouth area on the end of its body is usually surrounded with ciliated tentacles, which are used to capture suspended organic matter, detritus, and/or algae. These worms range in size from very tiny, a few millimeters, to about 20 inches (50 cm) in length. They arrive on/in live rock and are not harmful to the environment or its inhabitants and may serve as a foodstuff for larger crustaceans.
The rock living sipunculans generally tunnel into rock, and/or live in previously drilled holes. The end that protrudes has a small group of tentacles that is used to 'mop' the surface of rock and collect algal cells and detritus. Since this mouth-like extension, called the "introvert" can be extended quite far, it can clean fairly large areas of the rock surface without the worm leaving the safety of its hole. Those sand dwelling sipunculans appear more feather-duster-like and are suspension feeders, and there are also crevice dwelling sipunculans also.
