• Globorotalia opima Bolli subsp. continuosa Blow.—Jenkins, 1960:366, pl. 5 (partim), figs. 4a-c [lower Miocene Globigerinoides triloba triloba Zone, Lakes Entrance Oil Shaft, Victoria, Australia]. [Not Blow, 1959.]
• Globorotalia continuosa Blow.—Jenkins, 1966:9-10, pl. 2, figs. 9a-c [lower Miocene, lower Aquitanian stage, southwest France]. [Not Blow, 1959.]
• Globorotalia nana pseudocontinuosa Jenkins, 1967:1074-1077, fig. 4.20-22 (holotype), fig. 4.23-25 (paratype) [lower Miocene, G. (G.) woodi connecta Zone, Otaian Stage, North Island, New Zealand].
• Globorotalia (Turborotalia) nana pseudocontinuosa Jenkins.—Jenkins, 1971:124-125, pl. 12, figs. 336-341 [re-illustrated from Jenkins, 1967, pl. 1074, figs. 4.20-25].
• Globorotalia pseudocontinuosa Jenkins.—Berggren and Amdurer, 1973, pl. 27, figs. 11-15 [lower Miocene Zone N4 and Zone N5, DSDP Site 18, South Atlantic Ocean].—Jenkins, 1977:307, pl. 4, figs. 1, 2 [lower Miocene G. trilobus trilobus Zone, Sealab Trial Borehole, English Channel].—Jenkins, 1978, pl. 1, figs. 14-16 [lower Miocene G. woodi connecta Zone, DSDP Site 360, southeast Atlantic Ocean].—Hoskins, 1984, figs. 7.7-12 [lower Miocene G. trilobus trilobus Zone, Awamoan Stage, New Zealand], figs. 8:5-6 [middle Miocene P. glomerosa curva Zone, Clifdenian Stage, New Zealand], figs. 8:7-9 [lower Miocene G. woodi connecta Zone, Otaian Stage, New Zealand].—Jenkins and Srinivasan, 1986:813, pl. 5, figs. 2-4 [lower Oligocene G. angiporoides Zone, DSDP Site 593, Challenger Plateau, southwest Pacific Ocean].
• Paragloborotalia pseudocontinuosa (Jenkins).—Cifelli and Scott, 1986, figs. 1d and 1h [lower Miocene, G. (G.) woodi connecta Zone, Otaian Stage, North Island, New Zealand].—Spezzaferri and Premoli Silva, 1991:248, pl. XI, figs. 1a-c [lower Oligocene Subzone P21a, DSDP Hole 538A, Catoche Knoll, Gulf of Mexico], pl. XII, figs. 1a-c, 2a [lower Oligocene Zone P20, DSDP Hole 538A, Gulf of Mexico].—Spezzaferri, 1994:54, pl. 20, figs. 1a-c [re-illustration of specimen from Spezzaferri and Premoli Silva, 1991, pl. XI, figs. 1a-c].—Morgans and others, 2002, figs. 14M-O [lower Miocene G. incognita Zone, Altonian Stage, North Island, New Zealand].
• Not Paragloborotalia pseudocontinuosa (Jenkins).—Li and others, 2003b:16, pl. 2, fig. 26 [lower Oligocene Zone P18-P19, ODP Hole 1134A, Great Australian Bight, Indian Ocean], pl. 2, figs. 27, 28 [upper Oligocene Zone P22, ODP Hole 1134A, Great Australian Bight, Indian Ocean] (= P. semivera).—Wade and others, 2007:pl. II, figs. L, M [upper Oligocene Zone O5, ODP Hole 1218B, equatorial Pacific Ocean](= P. opima).

Jenkins (1960) described the occurrence of Globorotalia opima subsp. continuosa Blow in two distinct stratigraphic levels in the Lakes Entrance oil shaft of Victoria, in southeastern Australia. The lower occurrences are confined to the upper Oligocene-lower Miocene pre-Globoquadrina dehiscens dehiscens to Globigerinoides triloba triloba Zones, while the younger forms are limited to the upper Miocene Globorotalia menardii miotumida Zone. According to Jenkins (1960:366) these older forms “are a little larger” and the aperture is “a little larger” than the very similar younger forms. The two light microscope photomicrograph hypotypes illustrated by Jenkins and representing the two distinct levels, are indistinguishable. Jenkins (1967) went on to describe the older forms as a new subspecies: Globorotalia nana pseudocontinuosa. Jenkins (1967: 1076) concluded that the two taxa were homeomorphs; G. mayeri continuosa evolved from Globorotalia mayeri mayeri “well after the extinction of G. nana pseudocontinuosa”.

Blow (1959) reported a range for Globorotalia opima subsp. continuosa from the lower Miocene Catapsydrax stainforthi Zone to the lower Pliocene Sphaeroidinella seminulina Zone. According to Jenkins (1967:1076), pseudocontinuosa and continuosa are very similar and “morphologically indistinguishable”. Hoskins (1984, figs. 8:1-4) illustrated specimens identified as continuosa from the middle Miocene O. suturalis Zone (Lillburnian Stage, New Zealand) that closely resemble pseudocontinuosa based on the large spherical final chamber. Further study may warrant synonymizing pseudocontinuosa with continuosa. However, for now, we will continue to recognize two distinct taxa (e.g., Jenkins, 1971; Spezzaferri, 1994); P. pseudocontinuosa is here considered to be the Oligocene morphotype characterized by a slightly convex spiral side and more umbilical aspect of the high arched aperture, while P. continuosa is a longer ranging Miocene morphotype characterized by its flat spiral side and more extraumbilical aspect of the moderately high, comma-shaped aperture. [Leckie et al. 2018]

Paragloborotalia pseudocontinuosa is characterized by its spherical chambers that increase moderately rapidly as added. It is differentiated from P. continuosa by its more umbilical-extraumbilical, high arched aperture with a thickened rim (although the paratype more closely resembles continuosa), and more spherical chambers. The aperture in the holotype of pseudocontinuosa is loop shaped and distinctly higher than in the holotype of continuosa; the aperture of continuosa is more extraumbilical in position. It is distinguished from nana in having a higher arched aperture, a faster rate of chamber expansion, a more ovate test, and lobulate equatorial profile, and from both nana and opima in having a high loop-shaped aperture and moderate spire. Paragloborotalia pseudocontinuosa is also smaller than P. opima.

It is differentiated from incognita by its greater spiral-side convexity, radial spiral sutures, and more spherical final chamber, The rate of chamber inflation in P. pseudocontinuosa is similar to P. incognita but greater than in P. continuosa; the final chamber of pseudocontinuosa and incognita is distinctly more inflated than in continuosa, which also has a more extraumbilical aperture than the latter two taxa. Basically, incognita is larger and has a flatter spiral side and slightly curved spiral sutures, while continuosa differs from pseudocontinuosa in having a more extraumbilical aperture; there are gradations between all of these end-members. However, P. pseudocontinuosa has also previously been synonymised with P. incognita (e.g., Berggren and others, 1983; Kennett and Srinivasan, 1983; Li and others, 1992), indicating that there are subtle differences in the test morphology between these two taxa. Here we consider both to be valid taxa despite their similar morphologies. In addition, pseudocontinuosa ranges back to the early Oligocene, while incognita has its first occurrence in the earliest Miocene. The flatter spiral side and slightly curved sutures of incognita display advanced, transitional features between P. pseudocontinuosa and Globoconella zealandica.

Paragloborotalia pseudocontinuosa closely resembles semivera. Jenkins (1971) stated that most of the paratypes in the type sample of semivera have 4 chambers in the final whorl, which he classified as G. (T.) nana pseudocontinuosa Jenkins (also Hoskins, 1984). Jenkins (1971) and Hoskins (1984) also noted a complete range of variation between the two (sub)species in this lower Miocene sample (Awamoan Stage, G. trilobus trilobus Zone). Paragloborotalia pseudocontinuosa is differentiated from semivera by its higher, almost circular aperture, and in possessing fewer chambers (4) in the final whorl. Some specimens of pseudocontinuosa may have a kummerform final chamber (Hoskins, 1984; figs. 7:10-12). Paragloborotalia pseudocontinuosa is distinguished from acrostoma by having only 4 chambers in the final whorl; we propose that pseudocontinuosa gave rise to acrostoma in the early Miocene. [Leckie et al. 2018]

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