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Heterohelicacea

The Heterohelicacea are middle Jurassic to Oligocene planktonic forams included in the Globigerinidae, characterized by birserial or triserial tests, at least in the early stage, that may be reduced in the later stage but more commonly show chamber proliferation in the later stage. Aperture a low or high arch at the base of the final chamber or terminal in uniserial stage. Includes three families, the Guembelitriidae, Heterohelicidae, and Chiloguembelinidae.

The Treatise, part C, 1964 regards this group as the family Heterohelicidae within the Globigerinacea, a superfamily in the suborder Rotaliina, with Foraminifera regarded as a taxonomic order.