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Name derivation: |
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Many bristles -- Many (Poly-) bristles (-chaete) |
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Morphology: |
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Belonging to Phylum Annelida, the class of polychaetes are segmented, with a pair of parapodia bearing bristles on each segment. The first and last segments are specialized as "head" and "tail". Highly diverse in size (1 mm to 3 m in length) color, and motility (polychaetes have two different lifestyles; some are active crawlers and swimmers, but most are sessile tube-dwellers). The class includes more than 8,000 species (of approximately 9,000 species of annelids).
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Habitat |
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Almost all are marine, mainly benthic. Only a few truly freshwater species have been recognized in North America (Foster 1972). There are fewer than 50 known species of freshwater polychaetes in the entire world, and only 13 species occur in North America (Biology Institute of Ontario 2010).
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References: |
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Foster, N.M. Freshwater polychaetes (Annelida) of North America. US Environmental Protection Agency, Project # 18050 ELD, Contract # 14-12-894. Biology Institute of Ontario, P. D. N. Hebert (Lead Author);J. E. Duffy (Topic Editor) "Annelida (Aquatic)". In: Encyclopedia of Earth. Eds. Cutler J. Cleveland (Washington, D.C.: Environmental Information Coalition, National Council for Science and the Environment). [First published in the Encyclopedia of Earth February 19, 2010; Last revised Date February 19, 2010; Retrieved November 22, 2010.
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