Ribbon Worms

Ribbonworms feeding on coral

There are about 900 species of ribbon worms in oceans around the world. They are sometimes also known as proboscis worms because they can extend a proboscis to capture their food.

Most look like flatworms, but tend to be larger, thicker-bodied, and longer. Although most species are less than 20 cm in length, and some just a few millimetres long, a few species may measure several metres or more. Although most are pale, some are brightly coloured with patterns of yellow, orange, red and green.

Habitat

Most live in or on the sea floor, but some are deep water pelagic species. The many common shallow-water species live under shells and stones, or in marine algae. Some burrow into sand or mud. A few species have symbiotic relationships with crabs, bivalve molluscs and tunicates.

Feeding

Ribbon worms are entirely carnivorous, eating primarily crustaceans and annelid worms. The proboscis, which is used to capture prey, shoots out of the body under pressure and coils around the prey. Sticky toxic secretions from the proboscis help Ribbon Worms hold and immobilize their food.