Search results
Results From The WOW.Com Content Network
Nemertea is a phylum of animals also known as ribbon worms or proboscis worms, consisting of about 1300 known species. [ 2 ] [ 3 ] Most ribbon worms are very slim, usually only a few millimeters wide, although a few have relatively short but wide bodies.
The enoplan nemerteans have been regarded as highly derived based on a more complicated muscle arrangement in the body wall and a more complex nervous system. However, whether this is a plesiomorphic or apomorphic character is not clear, and recent molecular studies are inconclusive in this respect.
Because of the body plan of lophotrochozoan fossils, a phylogenetic analysis found the lophophorates as the sister group of annelids. Both groups share in common: the presence of chaetae secreted by microvilli ; paired, metameric coelomic compartments; and a similar metanephridial structure.
Geonemertes pelaensis is a species of terrestrial Nemertea. [1] Superficially, Geonemertes pelaensis resembles a land flatworm (family Geoplanidae) and lives in the same habitat, but it has an anterior exertile proboscis, whereas flatworms have a pharynx located in their ventral side at midlength of body. The number of eyes this nemertean can ...
Palaeonemertea is a class of primitive nemertean worm. It may be para- or polyphyletic, consisting of three to five clades and totalling about 100 species.. These worms have several apparently simple features and, as their name suggests, they are often considered to be the most primitive nemerteans.
Anopla (for changes in taxonomy, see reference from 2019) has long been used as name for a class of marine worms of the phylum Nemertea, characterized by the absence of stylets on the proboscis, the mouth being below or behind the brain, and by having separate openings for the mouth and proboscis.
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Pages for logged out editors learn more
Worms in this family have slightly flattened, rounded heads and approximately cylindrical bodies. Apart from the genera, Callinera and Carinina, worms in this family have paired cerebral sensory organs located on either side of the constriction where the head joins the body. Some species are red or brown, often with distinctive white bands or ...