Ribbon Worm

Nemertea is a phylum of animals also known as ribbon worms or proboscis worms, consisting of about 1,300 known species. Most ribbon worms are very slender, usually only a few millimeters wide, and many display patterns of yellow, orange, red and green coloration. All species possess a proboscis, held inside an internal cavity called the rhynchocoel when inactive, that everts to emerge just above the mouth and capture prey with venom; a highly extensible muscle pulls the proboscis back in once an attack ends. A few stubby-bodied species filter feed instead, using suckers at their front and back ends to attach to a host.