Taxonomy of Middle Miocene foraminifera from the northern Namibian continental shelf Author Bergh, Eugene W. 0000-0002-0765-4141 Marine Research Institute and Department of Geological Sciences, University of Cape Town, Private Bag X 3, Rondebosch, 7701, South Africa. & Department of Environmental and Geographical Sciences, University of Cape Town, Private Bag X 3, Rondebosch, 7701, South Africa; & Invertebrate palaeontology and Geology, Iziko South African Museum, P. O. Box 61, Cape Town 8000, South Africa. john. compton @ uct. ac. za; https: // orcid. org / 0000 - 0002 - 0765 - 4141 john.compton@uct.ac.za Author Compton, John S. Marine Research Institute and Department of Geological Sciences, University of Cape Town, Private Bag X 3, Rondebosch, 7701, South Africa. text Zootaxa 2022 2022-01-12 5091 1 1 55 journal article 2636 10.11646/zootaxa.5091.1.1 51b42715-ddb1-4b4a-aad4-8be0f600a287 1175-5326 5840434 ABC8AF70-F691-4D07-8F20-70934642C8BC Sphaeroidina bulloides d’Orbigny in Deshayes 1828 Pl. 5, figs. 3a–b Sphaeroidina bulloides d’Orbigny, 1826 , p. 267 ; LeRoy & Levinson, 1974 , p. 8 , pl. 5, fig. 2; Martin, 1981 , p. 36 , pl. 10, fig. 5; Papp & Schmid, 1985 , p. 96 , pl. 90, figs. 7–12; Lowry, 1987 , p. 379 , pl. 27, figs. 7a–c; Jones, 1994 , p. 91 , pl. 84, figs. 1–2; Yassini & Jones, 1995 , p. 160 , figs. 936–937; Robertson, 1998 , p. 196 , pl. 74, fig. 4; Kender et al. , 2008 , p. 516 , pl. 20, fig. 3; Holbourn et al ., 2013 , p. 520 . Sphaeroidina austriaca d’Orbigny, 1846 , p. 284 , pl. 20, figs. 19–21. Description : The test wall is calcareous, imperforate and its surface is smooth. The test is subglobular, with globular chambers separated by slightly depressed sutures. The last whorl contains three chambers. The aperture is located near the junction between three chambers and is crescentic in shape, with a bordering lip (pl. 5, fig. 3b). Remarks: The relative abundances of Sphaeroidina bulloides in this study decrease toward the deeper cores. In core 2658, S. bulloides formed one of the major species in some of the samples (<20%), and in cores 2670 and 2682, minor (<5%). The test sizes of Sphaeroidina bulloides in general are variable. Diameters in LeRoy & Levinson (1974) range between 0.23 and 1.15 mm . The diameter measured for specimens in this study is ~ 0.5 mm . Life strategy: This species is infaunal under suboxic ( Kaiho, 1994 ) to dysoxic conditions ( Pezelj et al., 2013 and references therein). Its bathymetric distribution stretches from the slope to abyssal depths ( Holbourn et al ., 2013 ). Global stratigraphic range: Sphaeroidina bulloides occurs from the Oligocene to Recent ( Jones, 1994 ; Holbourn et al ., 2013 ). Regional occurrence : This species occurs in Miocene-aged strata, stretching from the Congo Basin ( Kender et al. , 2008 ) to the outer continental shelf of Namibia , south of the Kunene River mouth (this study) and the southwestern shelf of South Africa ( Compton et al., 2004 ). Hay et al. (1984) reported the occurrence of Sphaeroidina bulloides in late Miocene to Pleistocene sediments on the slope off the Walvis Ridge. Low relative abundances (<1%) of this species occur along the slope of Namibia during the late Miocene , with higher abundances off the Orange River to the south (<15%). Wefer et al . (1998) recorded high relative abundances of this species (<80%) along the slope off the Walvis Ridge during the Pliocene, decreasing in abundance towards the south. Low relative abundances (<1%) of this species have been recorded to occur along the Namibian slope and minor abundances (<10%) along the southwestern slope of South Africa during the Pleistocene ( Wefer et al ., 1998 ). Lowry (1987) documented Sphaeroidina bulloides in surface sediments on the continental shelf between Lüderitz, Namibia and Cape Agulhas, South Africa .