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Nematomorpha
Nematomorpha , small (about 230 species) phylum of pseudocoelomates ; the horsehair worms . Most are very slender, elongated creatures found in ponds and streams, whose larvae live as parasites in arthropods. They emerge as adults for a brief time, then mate and die. A small number are planktonic in marine habitats and live as larvae in crabs or shrimps. Adults are simplified externally and internally; they have no excretory or circulatory systems and only a vestigial digestive tract. The female produces long strings of eggs. After hatching, the larva penetrates any convenient aquatic animal, but its development stops until it has found its way into an appropriate host, typically an insect. The adult nematomorph emerges when the host is in or near water; it molts once after emerging and takes up its brief adult existence. |
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"Nematomorpha." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "Nematomorpha." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1E1-Nematomo.html "Nematomorpha." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-Nematomo.html |
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Nematomorpha
Nematomorpha (hairworms; phylum Aschelminthes) A small class or phylum of pseudocoelomate, unsegmented worms, the vast majority of which are marine. Their narrow, hair-like bodies have a thick cuticle. All lack a true excretory system. The young are parasitic, and mature individuals are free-living in fresh water. They are first recorded from the Eocene.
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MICHAEL ALLABY. "Nematomorpha." A Dictionary of Zoology. 1999. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "Nematomorpha." A Dictionary of Zoology. 1999. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O8-Nematomorpha.html MICHAEL ALLABY. "Nematomorpha." A Dictionary of Zoology. 1999. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-Nematomorpha.html |
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