Glandulina laevigata ( d’Orbigny, 1826 )

Bergh, Eugene W. & Compton, John S., 2022, Taxonomy of Middle Miocene foraminifera from the northern Namibian continental shelf, Zootaxa 5091 (1), pp. 1-55 : 21

Glandulina laevigata ( d’Orbigny, 1826)

Pl. 4, figs. 6a–b

Nodosaria (Glandulina) laevigata var. ovata d’Orbigny, 1826, p. 252 , pl. 10, fig. 1–3; Brady 1884, p. 490, pl. 61, fig. 20–22; Cushman, 1921, p. 185, pl. 33, fig. 1; Cushman & Applin, 1926, p. 169, pl. 7, figs. 12–13.

Glandulina laevigata d’Orbigny, 1846, p. 29 , pl. 1, fig. 4–5; Sandidge, 1932, p. 360, pl. XXXII, fig. 15.

Glandulina laevigata var. ovata Ellisor, 1933 , pl. 2, fig. 6.

Description: The test wall is calcareous and smooth. The test shape is ovate, globular, tapering at each end and circular in transverse section with few chambers increasing toward the apertural end. The final chamber is the largest, comprising nearly two thirds of the test volume. The sutures are fine and flush. The aperture is radiate and projects slightly from the larger last chamber.

Remarks: Few tests comprising <1% of the total foraminiferal assemblage in core 2670 were recorded. Tests are moderate to large in size, ranging from 0.5 mm to nearly 1 mm in cross-section and 0.75 to 1.2 mm in length. The figured specimen of Glandulina laevigata in Sandidge (1932) is 0.5 mm in length.

This species is synonymised with Nodosaria (Glandulina) laevigata and Nodosaria laevigata ( Loeblich & Tappan, 1988) .

Life strategy: This species is infaunal and tolerant of low oxygen conditions ( Gupta, 1993).

Global stratigraphic range: Glandulina laevigata occurs from the Cretaceous to Recent ( Sandidge, 1932).

Regional occurrence: This species occurs in middle Miocene sediments on the Namibian outer continental shelf, south of the Kunene River mouth (this study).