Jenkins (1965) and Chaproniere (1988) distinguished G. brazieri from G. woodi on the basis of the aperture, which in G. brazieri is higher arched, more rounded and resembles a reverse droplet, commonly higher than it is wide, and on the chambers in the last whorl that increase more rapidly in size in G. brazieri. Kennett and Srinivasan (1983) describe the aperture of G. brazieri as symmetrically placed over the sutures of the penultimate and antepenultimate chambers. Retained here in the species G. brazieri are specimens possessing an aperture tending towards a reverse droplet shape together, as documented in the paratypes of Jenkins (1965), with those with a more rounded aperture typical of the holotype. Although paratype 5 of Jenkins (1965) shows a bulla covering the aperture, this structure has not been observed in our material. Jenkins (1965) suggested that G. brazieri evolved from G. woodi in the lower Miocene and identified the range of G. brazieri as restricted to the lower Miocene (from the Globoquadrina dehiscens Zone to the lower part of the Globigerina woodi connecta Zone = interval spanning Zones O7 to M1). However, Premoli Silva and Spezzaferri (1990) found this species occurring in Zone P20 in the Indian Ocean, and Spezzaferri (1994) recorded it in Subzone P21a in DSDP Holes 354 and 667A (equatorial Atlantic Ocean), 526A, 363 360, 516F (South Atlantic Ocean) and ODP Hole 709C (Indian Ocean). Thus, within our taxonomic and stratigraphic framework we suggest that G. brazieri was the ancestor of G. woodi and that G. brazieri evolved from G. paracancellata n. sp.
Catalog entries: Globigerina brazieri
Type images:Distinguishing features:
Parent taxon (Globoturborotalita): Trochospiral test with a single, large, open umbilical aperture. Cancellate wall. 4-4½ chambers in final whorl
This taxon: Like G. woodi but subquadrate test and aperture placed directly opposite the suture line
Morphology:
Wall type:
Character matrix
test outline: | Subquadrate | chamber arrangement: | Trochospiral | edge view: | Equally biconvex | aperture: | Umbilical |
sp chamber shape: | Globular | coiling axis: | Low-moderate | periphery: | N/A | aperture border: | Thin lip |
umb chbr shape: | Globular | umbilicus: | Wide | periph margin shape: | Broadly rounded | accessory apertures: | None |
spiral sutures: | Weakly depressed | umb depth: | Deep | wall texture: | Cancellate | shell porosity: | Macroperforate: >2.5µm |
umbilical or test sutures: | Moderately depressed | final-whorl chambers: | 3.5-4 | N.B. These characters are used for advanced search. N/A - not applicable |
Geographic distribution
Isotope paleobiology
Phylogenetic relations
G. brazieri is distinguished from G. woodi by its subquadrate test and by the apertural placement directly opposite the suture line. Similarities in surface ultrastructure and presence of morphologically transitional forms indicate that G. brazieri was derived from G. woodi. [Kennett & Srinivasan 1983, followed by Aze et al. 2011]
Most likely ancestor: Globoturborotalita paracancellata - at confidence level 2 (out of 5). Data source: Spezzaferri et al. 2018.
Likely descendants: Globoturborotalita woodi;
plot with descendants
Geological Range:
Notes: This species has been observed from Zone O3 (Subzone P21a of Premoli Silva and Spezzaferri, 1990) in the Indian Ocean ODP Hole 709B to Zone M4? (Kennett and Srinivasan, 1983). According to Huber (1991) it disappears within Chron C6N at the Kerguelen Plateau. [Spezzaferri et al. 2018]
Last occurrence (top): within M4 zone (16.38-17.54Ma, top in Burdigalian stage). Data source: Kennett & Srinivasan 1983
First occurrence (base): within O3 zone (29.18-30.28Ma, base in Rupelian stage). Data source: Kennett & Srinivasan 1983
Plot of occurrence data:
Primary source for this page: Spezzaferri et al. 2018 - Olig Atlas chap.8 p.225; Kennett & Srinivasan 1983, p.43
Blow, W. H. (1959). Age, correlation, and biostratigraphy of the upper Tocuyo (San Lorenzo) and Pozon Formations, eastern Falcon, Venezuela. Bulletins of American Paleontology. 39(178): 67-251. gs Chaproniere, G. C. H. (1988). Globigerina woodi from the late Oligocene and early Miocene of southeastern Australia. Journal of Foraminiferal Research. 18: 105-115. gs Huber, B. T. (1991c). Paleogene and Early Neogene Planktonic Foraminifer Biostratigraphy of Sites 738 and 744, Kerguelen Plateau (Southern Indian Ocean). Proceedings of the Ocean Drilling Program, Scientific Results. 119: 427-449. gs Jenkins, D. G. (1966b). Planktonic foraminiferal zones and new taxa from the Danian to lower Miocene of New Zealand. New Zealand Journal of Geology and Geophysics. 8 [1965](6): 1088-1126. gs Jenkins, D. G. (1971). New Zealand Cenozoic Planktonic Foraminifera. New Zealand Geological Survey, Paleontological Bulletin. 42: 1-278. gs Kennett, J. P. & Srinivasan, M. S. (1983). Neogene Planktonic Foraminifera. Hutchinson Ross Publishing Co., Stroudsburg, Pennsylvania. 1-265. gs Olsson, R. K. & Hemleben, C. (2006). Taxonomy, biostratigraphy, and phylogeny of Eocene Globanomalina, Planoglobanomalina n. gen and Pseudohastigerina. In, Pearson, P. N., Olsson, R. K., Hemleben, C., Huber, B. T. & Berggren, W. A. (eds) Atlas of Eocene Planktonic Foraminifera. Cushman Foundation for Foraminiferal Research, Special Publication . 41(Chap 14): 413-432. gs O Olsson, R. K., Hemleben, C. & Pearson, P. N. (2006b). Taxonomy, biostratigraphy, and phylogeny of Eocene Dentoglobigerina. In, Pearson, P. N., Olsson, R. K., Hemleben, C., Huber, B. T. & Berggren, W. A. (eds) Atlas of Eocene Planktonic Foraminifera. Cushman Foundation for Foraminiferal Research, Special Publication . 41(Chap 13): 401-412. gs O Premoli Silva, I. & Spezzaferri, S. (1990). Paleogene planktonic foraminifer biostratigraphy and paleoenvironmental remarks on paleogene sediments from Indian Ocean sites, Leg 115. Proceedings of the Ocean Drilling Program, Scientific Results. 115: 277-314. gs Spezzaferri, S. (1994). Planktonic foraminiferal biostratigraphy and taxonomy of the Oligocene and lower Miocene in the oceanic record. An overview. Palaeontographia Italica. 81: 1-187. gs Spezzaferri, S., Olsson, R. K., Hemleben, C., Wade, B. S. & Coxall, H. K. (2018d). Taxonomy, biostratigraphy, and phylogeny of Oligocene and Lower Miocene Globoturborotalita. In, Wade, B. S., Olsson, R. K., Pearson, P. N., Huber, B. T. & Berggren, W. A. (eds) Atlas of Oligocene Planktonic Foraminifera. Cushman Foundation for Foraminiferal Research, Special Publication . 46(Chap 8): 231-268. gs References:
Globoturborotalita brazieri compiled by the pforams@mikrotax project team viewed: 12-11-2024
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