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''Carterina'' is a genus in the Foraminifera (Kingdom Protista). It is the only known genus of the order Carterinida and family Carterinidae. (Loeblich & Tappan 1964) The type species is ''Carterina spiculotesta'' (Carter, 1877) Brady, 1884. The genus is described from specimens gathered during the Challenger expedition's circumnavigation of the Earth from 1872-1876.〔http://www.foraminifera.eu/brady.php〕 The test (or shell) of ''Carterina'' begins as a low, free, umbilicate trochospiral (concavo-convexly coiled with a central depression) in the early growth stage, becoming attached and spreading irregularly in later stages. Chambers become partially subdivided by secondary septa, reaching as many a 15 per chamber in later chambers.(Loeblich & Tappan 1964, 1988) Walls are composed of two sizes of fusiform spicules of low-Mg calcite, larger structural spicules in a ground mass of smaller spicules. The spicules are secreted by the protoplasm, crystallographic c-axes parallel to the elongation, and set parallel to the test surface. The order and family have the same characteristics as the genus. ''Carterina'' is known from the Eocene of Spain and is widespread in shallow tropical waters in the Holocene, but is unknown from intervening epochs. ''Carterina'' and Carterinidae were previously included in the Geological Society of America's ''Treatise on Invertebrate Paleontology'' part C. in the Rotaliida as the superfamily Carterinacea. (Loeblich and Tappan 1964) ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Carterina」の詳細全文を読む スポンサード リンク
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