Siphonina pulchra Cushman, 1919

Bergh, Eugene W. & Compton, John S., 2022, Taxonomy of Middle Miocene foraminifera from the northern Namibian continental shelf, Zootaxa 5091 (1), pp. 1-55 : 25-26

Siphonina pulchra Cushman, 1919

Pl. 5, figs. 4–6

Siphonina pulchra Cushman, 1919, p. 42 , pl. 14, fig. 7a–c; Cushman, 1922a, p. 49, pl. 7, fig. 11–12; Cushman, 1927b, p. 8, pl. 2, fig. 5; Cushman, 1931, p. 69, pl. 14, fig. 2–3; Palmer, 1945, p. 61.

Description: The test wall is calcareous and perforate. The test is circular in outline, rounded, compressed and biconvex in side view. There are five chambers in the last whorl, gradually increasing toward the apertural end of the test. Sutures are coarsely perforate, distinct and oblique, radiating from the broad macroperforate centre of the test. The periphery of the test is unevenly carinate around the margin. The chambers are separated by flush oblique sutures. The elliptical-shaped aperture is produced on a broad tubular neck with a thick bordering lip.

Remarks: The relative abundances recorded for S. pulchra are trace (<1%) in all three cores. Several specimens were found to be partially broken or with the aperture missing. The diameter of the tests in Cushman (1931) was reported to be 0.65 mm. Tests in this study are slightly smaller, measuring 0.5 mm in diameter.

Life strategy: The genus Siphonina is epifaunal and prefers oxic bottom water conditions ( Kaiho, 1994), with a bathymetric distribution from shelf to slope depths ( Phleger & Parker, 1951).

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