Praeorbulina curva ( Blow, 1956 )

Bergh, Eugene W. & Compton, John S., 2022, Taxonomy of Middle Miocene foraminifera from the northern Namibian continental shelf, Zootaxa 5091 (1), pp. 1-55 : 36

Praeorbulina curva ( Blow, 1956)

Pl. 8, fig. 8

Globigerinoides glomerosa curva Blow, 1956, p. 64 , text-fig. 1, 9–14.

Praeorbulina glomerosa curva Bolli et al., 1985, p. 199 , figs. 23.5, 24.6; Kennett & Srinivasan, 1985, p. 82, pl. 18, figs. 3-4.

Description: The test surface is cancellate-spinose. The test is trochospiral, globular and semi-circular or subspheroidal in cross section. The final chamber envelops earlier chambers. The proportion of the enveloping chamber is variable, with 40 to 70% of the test that can be covered. Apertures form slits along the margins of the ultimate, penultimate and earlier chambers. Numerous narrow slit-like apertures can cover the test along the sutures. The sutures become more incised in the later chambers.

Remarks: This species occurs in minor abundances in the cores. The tests are moderate in size, measuring up to 0.4 mm in diameter.

Environmental preferences: Praeorbulina curva is considered to be a temperate to warm water tropical species ( Kennett & Srinivasan, 1983).

Global stratigraphic range: This species has been recorded to occur from the early (Burdigalian) to middle Miocene – Langhian ( Kennett & Srinivasan, 1983; Wade et al., 2011).

Regional occurrence: Praeorbulina curva is documented to occur in middle Miocene-aged sediments of the northern Namibian continental shelf, south of the Kunene River mouth (this study) .