Asterigerinacea
Encyclopedia
The Asterigerinacea is a superfamily of foraminifera
Foraminifera
The Foraminifera , or forams for short, are a large group of amoeboid protists which are among the commonest plankton species. They have reticulating pseudopods, fine strands of cytoplasm that branch and merge to form a dynamic net...

 included in the order Rotaliida.
It is a rather new group in terms of its recognition having been proposed by Loeblich and Tappan ca. 1988 and is formed by combining three families previously included in other rotaliid superfamlies. These are the Episomariidae and Asterigerinidae which had been included in the Discorbacea
Discorbacea
Discorbacea is a superfamily of rotaliid foraminifera, with a range extending from the Middle Triassic to the present, characterized by chambers arranged in a low trochspiral; an umbilical or interiomarginal aperture, with or without supplementary apertures; and a wall structure that is optically...

 and the Amphisteginidae which was included in the Orbiotoidacea

Asterigerinacea are characterized by a trochospiral or nearly planispiral arrangement of the chambers, which are fully or partially subdivided by internal partitions. The primary aperture is commonly on the interior margin and secondary apertures are commonly along the sutures. Apertures may also form on the chamber surfaces as well. Test walls are composed of optically radial calcite.

The Asterigerinacea range from the Cretaceous to Recent, the oldest family being the Asterigerinidae.
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