Gnathostomula

	Gnathostomula Gnathostomulidae is a family of worms belonging to the order Bursovaginoidea Bursovaginoidea is one of the two orders in the phylum Gnathostomulida. Appearance and anatomy Bursovaginoids are rather small, ranging from a half of a millimeter to a full millimeter in length. Many species in the order Bursovaginoidea have .... Genera: * '' Chirognathia'' Sterrer & Sørensen, 2006 * '' Corculognathia'' Ehlers & Ehlers, 1973 * '' Gnathostomula'' Ax, 1956 * '' Ratugnathia'' Sterrer, 1991 * '' Semaeognathia'' Riedl, 1970 References {{Taxonbar, from=Q1900171 Gnathostomulida Platyzoa families ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Worm Worms are many different distantly related bilateral animals that typically have a long cylindrical tube-like body, no limbs, and no eyes (though not always). Worms vary in size from microscopic to over in length for marine polychaete worms (bristle worms); for the African giant earthworm, ''Microchaetus rappi''; and for the marine nemertean worm (bootlace worm), ''Lineus longissimus''. Various types of worm occupy a small variety of parasitic niches, living inside the bodies of other animals. Free-living worm species do not live on land but instead live in marine or freshwater environments or underground by burrowing. In biology, "worm" refers to an obsolete taxon, ''vermes'', used by Carolus Linnaeus and Jean-Baptiste Lamarck for all non-arthropod invertebrate animals, now seen to be paraphyletic. The name stems from the Old English word ''wyrm''. Most animals called "worms" are invertebrates, but the term is also used for the amphibian caecilians and the slowworm '' A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Bursovaginoidea Bursovaginoidea is one of the two orders in the phylum Gnathostomulida. Appearance and anatomy Bursovaginoids are rather small, ranging from a half of a millimeter to a full millimeter in length. Many species in the order Bursovaginoidea have a narrow neck, making their head stand out more than other bursovagionoids and all filospermoids. Bursovaginoids, unlike filospermoids, have paired sensory organs and a penis. Also, all species in Bursovaginoidea have a sperm-storage organ called a Bursa (Anatomy), bursa. In suborder Scleroperalia, the bursa is cuticular, while in Conophoralia it is not. Species in order Conophoralia tend to have larger sperm than those in Sceloperalia. Distribution Sightings of bursovaginoids have been reported in various parts of the world, including England and the north-western and south-eastern parts of the United States. Bursovaginoids mostly live in oceans near the coasts, in depths of under 500 meters (1650 feet), most commonly around 300. F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Gnathostomula Gnathostomulidae is a family of worms belonging to the order Bursovaginoidea Bursovaginoidea is one of the two orders in the phylum Gnathostomulida. Appearance and anatomy Bursovaginoids are rather small, ranging from a half of a millimeter to a full millimeter in length. Many species in the order Bursovaginoidea have .... Genera: * '' Chirognathia'' Sterrer & Sørensen, 2006 * '' Corculognathia'' Ehlers & Ehlers, 1973 * '' Gnathostomula'' Ax, 1956 * '' Ratugnathia'' Sterrer, 1991 * '' Semaeognathia'' Riedl, 1970 References {{Taxonbar, from=Q1900171 Gnathostomulida Platyzoa families ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Gnathostomulida Gnathostomulids, or jaw worms, are a small phylum of nearly microscopic marine animals. They inhabit sand and mud beneath shallow coastal waters and can survive in relatively anoxic environments. They were first recognised and described in 1956. Anatomy Most gnathostomulids measure in length. They are often slender to thread-like worms, with a generally transparent body. In many Bursovaginoidea, one of the major group of gnathostomulids, the neck region is slightly narrower than the rest of the body, giving them a distinct head. Like flatworms they have a ciliated epidermis, but in contrast to flatworms, they have one cilium per cell. The cilia allow the worms to glide along in the water between sand grains, although they also use muscles, allowing the body to twist or contract, for movement. They have no body cavity, and no circulatory or respiratory system. The nervous system is simple, and restricted to the outer layers of the body wall. The only sense organs are modified c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]