ABSTRACT The taxonomy, phylogeny, and biostratigraphy of Oligocene Turborotalita is reviewed. We recognize two species in the Oligocene, Turborotalita praequinqueloba Hemleben and Olsson and Turborotalita quinqueloba (Natland). The two species are distinguished primarily by the number of chambers in the final whorl (typically 4-4½ versus 4½-5½ respectively). We extend the stratigraphic range of T. quinqueloba down through the Oligocene and into the upper Eocene, making it the longest-lived of all the extant morphospecies. Combined with recently published research on the earliest Paleocene, it appears likely that Turborotalita represents a distinct clade that persisted for the entire Cenozoic, having first appeared in the immediate aftermath of the Cretaceous / Paleogene mass extinction.

ABSTRACT The taxonomy, biostratigraphy, and phylogeny of Oligocene Cassigerinella is reviewed. Cassigerinella is in Superfamily Guembelitrioidea and Family Cassigerinellidae. It is distinguished by its ‘twisted enrolled-biserial’ coiling mode and distinctive test microstructure, with minute-scale internal ornamentation (‘endospikes’). Only two species occur in the Oligocene and are recognized as valid in this work: Cassigerinella chipolensis (Cushman and Ponton) and Cassigerinella eocaenica Cordey.