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
Dentalina albatrossi
(
Cushman, 1923a
)
Pl. 1, fig. 10
Nodosaria vertebralis
var.
albatrossi,
Cushman, 1923a
, p. 47
, pl. 15, fig. 1.
Dentalina albatrossi
,
Jones, 1994
, p. 76
, pl. 64, figs. 11–12, 14;
Hanagata & Nobuhara, 2014
, p. 25
, fig. 9.12–9.13.
Description:
The wall is calcareous, hyaline. The test is elongate, slightly arcuate and uniserial, with the initial chamber possessing a short spine. Longitudinal continuous costae cover the test surface. The sutures are not depressed for most of the length of the test, except for the last few chambers towards the terminal end of the test. The chambers enlarge gradually toward the terminal end. The terminal chambers are also more oval in shape, compared to the initial portion of the test. The aperture is slightly protruding, terminal and radiate.
Remarks:
Few tests of this species were found, comprising <1% of the total benthic foraminifera assemblage in core 2670. The tests are up to
3 mm
long and thin, measuring
0.15 mm
in cross-section.
Life strategy:
This species is infaunal and adapted to suboxic to dysoxic conditions (
Kaiho, 1994
,
1999
).
Global stratigraphic range:
Dentalina albatrossi
is documented to occur from the Miocene to Recent (
Jones, 1994
).
Regional occurrence:
This study records
D. albatrossi
to occur in middle Miocene sediments on the Namibian outer continental shelf, south of the
Kunene
River
mouth.