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Histriobdellidae
Histriobdellidae is a family of annelids belonging to the order Eunicida. Genera: * ''Histriobdella'' Van Beneden, 1858 * ''Histriodrilus'' Foettinger, 1884 * ''Steineridrilus'' Zhang, 2014 * ''Stratiodrilus'' Haswell, 1900 References {{Taxonbar, from=Q5135427 Annelids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annelids
The annelids (Annelida , from Latin ', "little ring"), also known as the segmented worms, are a large phylum, with over 22,000 extant species including ragworms, earthworms, and leeches. The species exist in and have adapted to various ecologies – some in marine environments as distinct as tidal zones and hydrothermal vents, others in fresh water, and yet others in moist terrestrial environments. The Annelids are bilaterally symmetrical, triploblastic, coelomate, invertebrate organisms. They also have parapodia for locomotion. Most textbooks still use the traditional division into polychaetes (almost all marine), oligochaetes (which include earthworms) and leech-like species. Cladistic research since 1997 has radically changed this scheme, viewing leeches as a sub-group of oligochaetes and oligochaetes as a sub-group of polychaetes. In addition, the Pogonophora, Echiura and Sipuncula, previously regarded as separate phyla, are now regarded as sub-groups of polycha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eunicida
Eunicida is an order of polychaete worms. Characteristics Members of this order have an elongated, segmented body and a distinct head, normally with a separate peristomium and prostomium. Many, but not all, live in tubes which vary from a mucous sheath to a tough, horny casing. The palps vary from globular to cylindrical and there are from 0 to 7 antennae, usually smooth but occasionally jointed. There is a muscular pharynx with a dorsal pair of mandibles and a set of ventral, toothed, maxillary plates. Some species have tentacular cirri and all have unbranched parapodia. In some species, dorsal cirri, branchiae, ventral cirri and chaetae occur, but not in others. Natural History Museum. Retrieved 2012-01-17. Fossil record The |
