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Monoplacophora

Monoplacophora (phylum Mollusca) A class of primitive, almost bilaterally symmetrical, univalved molluscs, whose limpet-shaped shell of calcium carbonate consists of an external periostracum, a prismatic layer, and an internal, nacreous deposit. The circular foot and radula are ventrally placed, and the internal organs appear to be metamerically segmented, although some authorities question the evidence for metamerism, suggesting that monoplacophoran segmentation is not true metamerism but a secondary replication of structures such as has occurred in chitons and Nautilus. Typically, Monoplacophora have paired muscle scars. All are marine, benthic filter-feeders. Fossil forms inhabited shallow water, but modern forms occur in deep water. They first appeared in the Lower Cambrian.

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"Monoplacophora." A Dictionary of Zoology. . Encyclopedia.com. 17 Dec. 2017 <http://www.encyclopedia.com>.

"Monoplacophora." A Dictionary of Zoology. . Encyclopedia.com. (December 17, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/monoplacophora-0

"Monoplacophora." A Dictionary of Zoology. . Retrieved December 17, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/monoplacophora-0

Monoplacophora

Monoplacophora (phylum Mollusca) Class of primitive, almost bilaterally symmetrical, univalved molluscs, whose limpet-shaped shell of calcium carbonate consists of an external periostracum (the outer, non-calcareous layer), a prismatic layer, and an internal, nacreous deposit. The internal organs are metamerically segmented, and the circular foot and radula are ventrally placed. Typically, Monoplacophora have paired muscle scars. All are marine, benthic filter-feeders. Fossil forms inhabited shallow water, but modern forms occur in deep water. They first appeared in the Lower Cambrian.

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Pick a style below, and copy the text for your bibliography.

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"Monoplacophora." A Dictionary of Earth Sciences. . Encyclopedia.com. 17 Dec. 2017 <http://www.encyclopedia.com>.

"Monoplacophora." A Dictionary of Earth Sciences. . Encyclopedia.com. (December 17, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/monoplacophora

"Monoplacophora." A Dictionary of Earth Sciences. . Retrieved December 17, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/monoplacophora