''Discorbis'' is a genus of

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "t ...

Foraminifera (Kingdom

Protista A protist () is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor), the excl ...

in paleontological classifications), that made its first appearance during the

Eocene The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''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 The ''Treatise on Invertebrate Paleontology'' (or ''TIP'') published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and co ...

. As an alternative it may be included in the family Pegidiidae, which is elevated from the rotaliid subfamily Pegidiinae.

References

* * 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 Augustine Cushman, Joseph A. Cushman, 1950. Foraminifera, their classification and economic use. Harvard University Press, Cambridge, Massachusetts. 4th edition, 1950 {{Taxonbar, from=Q5281688 Discorbidae Rotaliida genera