• Globorotalia birnageae Blow, 1959:210-211, pl. 17, figs. 108a-c [lower Miocene Globigerinatella insueta Zone, Pozón Fm., eastern Falcón, Venezuela].—Poore, 1979:470, pl. 10, figs. 4, 5, 7, 8 [lower Miocene Zone N7, DSDP Site 407, North Atlantic Ocean].—Salvatorini and Cita, 1979, pl. 9, figs. 10, 15, 16 [lower Miocene Zones N7 and N8, DSDP Site 397, eastern North Atlantic Ocean].—Chaisson and Leckie, 1993:160, pl. 4, figs. 19-22 [lower Miocene Subzone N4b, Hole 806B, Ontong Java Plateau, western equatorial Pacific Ocean].—Spezzaferri, 1994:58, pl. 26, figs. 1a-c [lower-middle Miocene Zone N8/9, DSDP Hole 17A, eastern South Atlantic Ocean], fig. 3 [lower Miocene Subzone N4b, ODP Hole 667A, eastern equatorial Atlantic Ocean].
• Globorotalia (Fohsella) sp. cf. G. (F.) birnageae Blow.—Chaproniere, 1981:125-126, figs. 12Fa-c [upper Oligocene to lower Miocene, Ashmore Reef No. 1 Well, northwest Australia].
• Globorotalia (Fohsella) birnageae Blow.—Kennett and Srinivasan, 1983:94, pl. 21, figs. 6-8 [lower Miocene Zone N8, DSDP Site 289, Ontong Java Plateau, western equatorial Pacific Ocean].
• Fohsella birnageae (Blow).—Norris, 1998:466, pl. 1, fig. 5 [middle Miocene Zone N8, ODP Hole 959A, eastern equatorial Atlantic Ocean].
• Globorotalia (Turborotalia) mendacis Blow, 1969:390-391, pl. 38, figs. 5, 6 [upper Oligocene Zone N3, JOIDES Drillhole 3, Blake Plateau, western North Atlantic Ocean].
• Globorotalia (Fohsella) kugleri mendacis Blow.—Chaproniere, 1981:126, figs. 12Ca-c [upper Oligocene to lower Miocene, Ashmore Reef No. 1 Well, northwest Australia].
• Turborotalita primitiva Brönnimann and Resig, 1971:1287-1288, pl. 26, figs. 5-9 [upper Oligocene Zone N2, DSDP Hole 64.1, Ontong Java Plateau, western equatorial Pacific Ocean].
• Paragloborotalia? laccadivensis (Fleisher).—Spezzaferri, 1994:57, pl. 9, figs. 2a-c [lower Miocene Zone N5, DSDP Hole 526A, Walvis Ridge, eastern South Atlantic Ocean], pl. 9, figs. 3a-d [upper Oligocene Zone P22, DSDP Hole 526A, Walvis Ridge, eastern South Atlantic Ocean]. [Not Fleisher, 1974.]
• Not Turborotalia (Turborotalia) birnageae (Blow).—Fleisher, 1974:1035, pl. 18, fig. 9 [lower Miocene Zone N7-N8, DSDP Site 219, Arabian Sea] = ?Paragloborotalia siakensis (LeRoy).
• Not Globorotalia (Turborotalia) mendacis Blow.—Brönnimann and Resig, 1971:1314, pl. 39, figs. 6-8 [lower Miocene Zone N4, DSDP Hole 64.1, Ontong Java Plateau, western equatorial Pacific Ocean].—Quilty, 1976:646, pl. 12, figs. 21, 22 [lower Miocene Zone N4, DSDP Site 320, southeastern Pacific Ocean] = Paragloborotalia kugleri (Bolli).

Paragloborotalia birnageae and its junior synonyms have previously been attributed to a number of genera, including Globorotalia, Fohsella, and Turborotalita, but is placed here within Paragloborotalia based on its coarsely cancellate wall, and close resemblance with the P. nana-P. pseudokugleri-P. kugleri lineage. As part of our investigations, we have examined the topotypes of P. birnageae housed at the Natural History Museum in London, Blow collection (P49680, P49688); they are very consistent with the holotype, including the extended final chamber.

Globorotalia mendacis (Blow, 1969) is considered to be a junior synonym of P. birnageae. Both taxa have ~6 embracing chambers in the final whorl, a compact test with mostly closed umbilicus and a low aperture with a thin lip, and slightly curved dorsal sutures. Blow (1969) chose a distinctly biconvex specimen with a subacute peripheral margin (Pl. 5.2, Figs. 4-6) for the holotype. However, there is a complete gradation between forms with a broadly rounded margin (P. birnageae s.s.) and specimens that have a subacute margin. Globorotalia mendacis has long been considered a junior synonym of P. kugleri (Stainforth and others, 1975; Bolli and Saunders, 1985). However, our investigations of the holotype reveal that it is synonymous with P. birnageae based on the circular, weakly lobulate equatorial outline, kummerform final chamber with low aperture and flap-like lip. Blow (1979:148) notes that “superficially it [birnageae] bears some general morphological resemblances to G. (T.) kugleri, G. (T.) pseudokugleri and, especially, G. (T.) mendacis”.

Specimens of Paragloborotalia? laccadivensis reported by Spezzaferri (1994) are also likely synonymous with birnageae. The tiny, 5-6 chambered laccadivensis consistently first appears in mid-Oligocene Subzone P21a (= Zone O3/O4; Spezzaferri, 1994). Therefore, these mid-Oligocene to early Miocene forms are probably not the same taxon described by Fleisher (1974) as Globanomalina laccadivensis from the upper Eocene of the Arabian Sea. In her description of the forms she attributed to P.? laccadivensis, Spezzaferri (1994:57) notes: “Sutures are slightly depressed and radial on both sides”. As observed in other lineages of Paragloborotalia, radial spiral sutures are the ancestral condition in all early and mid Oligocene taxa (through Subzone P21a = O3-O4); spiral sutures of birnageae become more curved in the late to latest Oligocene (Zone P22 = O6 and O7).

Turborotalita primitiva was described by Brönnimann and Resig from the upper Oligocene of the southwestern Pacific Ocean and is considered here to be within the morphologic variability of P. birnageae. Although the type specimen is of rather poor quality and equivocal in its identification, it fits best as within the birnagaeae plexus. Moreover, we have re-examined the type level of T. primitiva in DSDP Hole 64A and found specimens attributable to P. birnageae (Pl. 5.3, Fig. 16). [Leckie et al. 2018]

Paragloborotalia birnageae is distinguished from P. pseudokugleri in having less depressed sutures, a less lobulate test, and a lower aperture. It differs from P. siakensis, P. mayeri, P. semivera, and P. kugleri in being less ovate and more circular in equatorial profile, and in having a nearly closed to closed umbilicus with a distinctive low aperture with lip or apertural flap/flange. The last chamber and aperture may resemble Turborotalita quinqueloba, but P. birnageae has a cancellate wall and a less lobulate equatorial profile (e.g., see Pearson and Wade, 2009). [Leckie et al. 2018]

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