Praeorbulina curva (Blow 1956)
- Dataset
- Taxonomy of Middle Miocene foraminifera from the northern Namibian continental shelf
- Rank
- SPECIES
Classification
- kingdom
- Chromista
- phylum
- Foraminifera
- class
- Globothalamea
- order
- Rotaliida
- family
- Globigerinidae
- genus
- Praeorbulina
- species
- Praeorbulina curva
description
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.
discussion
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).