Phylum: Nemertea

 

Norwegian: slimormer

(Rye - The Trondheim fjord / 8 meters / 1.04.2004)

This phylum includes more than 900 registered, mainly marine, species. They seem to have existed on earth for 500 million years, since the Cambrian period. Usually they feed on scavenges and dead animals. Some live in symbiotic relationships with mussels, while other species are parasites on marine invertebrates. Food is located by chemical signals or simply by pure chance. Even species equipped with eyes do not necessarily use them to find food.

A common feature of many of the ribbon worms is the extremely thin and elongated, unsegmented body. Some can reach a length of 30 meters with a body diameter of only a few millimeters. A digestion channel runs in full body length from the primitive head to the tail end. The ribbon worms have separate mouth and anus.