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
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)
.