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''Discorbis'' is a benthic Foraminfera genus, (Kingdom Protista in paleontological classifications), that made its first appearance during the Eocene. Its present distribution is cosmopolitan. ''Discorbis'' produces a smooth plano-convex to unequally biconvex trochospiral test (shell) with a flattened umbilical side, taking up about two and a half whorls, with seven to ten chambers in the final whorl. The test wall is calcareous, thin, optically radial, and finely to coarsely perforate. Sutures are depressed and curved to nearly radial. The umbilical region is covered by triangular flaps that extend from the umbilical margin of each chamber, forming a small chamberlet beneath. The aperture is a low, interiomarginal arch, outside the umbilicus. The classification here is that of , 1964, in the Treatise on Invertebrate Paleontology. As an alternative it may be included in the family Pegidiidae, which is elevated from the rotaliid subfamily Pegidiinae. ==References== * Alfred R. Loeblich and Helen Tappan, 1964. Sarcodina, chiefly "Thecamoebians" and Foraminiferida. Treatise on Invertebrate Paleontology, Part C, Protista 2. Geological Society of America and University of Kansas Press, 1964. *Loeblich and Tappan, 1988. Forminiferal Genera and their classification Geological Survey of Iran, (e-book) 2005. () *Loeblich and Tappan, 1992. Systematics of Modern Foraminifera, revised in Sen Gupta (ed) 2002, Modern Foraminifera () ''see also'' *Joseph A. Cushman, 1950. Foraminifera, their classification and economic use. Harvard University Press, Cambridge, Massachusetts. 4th edition, 1950 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「Discorbis」の詳細全文を読む スポンサード リンク
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