Descriptive characteristic

A key defining feature of the Nemertea is there proboscis which is housed in a true coelom called the rhynchocoel. The proboscis is everted in the coelom, where it shoots out and wraps around its prey and kills it, the proboscis is then retracted back into the rhynchocoel bringing the prey with it. Nemerteans are predators of crustaceans, annelids, Mollusca and other Nemerteans, and are capable of consuming prey many times wider then themselves.

The distinction between the predatory attacks (based on proboscis being armed/unarmed) splits the phylum into two different classes. The Anopla class is unarmed and secretes a sticky fluid and an added toxin which immobilizes the prey and class Enopla has a sharp stylet on its proboscis which stabs the prey and injects toxins