Globigerina archaeobulloides


Classification: pf_cenozoic -> Globigerinidae -> Globigerina -> Globigerina archaeobulloides
Sister taxa: G. bulloides, G. falconensis, G. umbilicata, G. archaeobulloides, G. officinalis, G. sp.,

Taxonomy

Citation: Globigerina archaeobulloides Hemleben and Olsson, in Spezzaferri et al. 2018
Rank: species
Taxonomic discussion:

Globigerina archaeobulloides n. sp. traces the development of the bulloides-type wall to the lowermost Oligocene Zone O1. Globigerina officinalis Subbotina has generally been regarded as ancestral to G. bulloides and can be regarded as a transitional species from a subbotinid ancestor (see discussion in Olsson and others, 2006). The wall texture of G. officinalis in the Eocene, however, is not a fully developed bulloides-type wall in that the pore concentration is lower (~50 pores/50 mm2 area); but the species develops a higher pore concentration in the lower Oligocene (72-85 pores/50 mm2 area). Globigerina archaeobulloides is morphologically similar to G. bulloides and has a fully developed bulloides-type wall. [Spezzaferri et al. 2018]

Catalog entries: Globigerina archaeobulloides

Type images:

Distinguishing features: Like G. officinalis but with lobed peripheral outline, and fully developed bulloides-type wall

NB These concise distinguishing features statements are used in the tables of daughter-taxa to act as quick summaries of the differences between e.g. species of one genus.
They are being edited as the site is developed and comments on them are especially welcome.

Description


Diagnostic characters:

Globigerina archaeobulloides n. sp. is distinguished by its small globular test, umbilical aperture and bulloides-type wall. No such form has to our knowledge been described or imaged previously. It differs from G. bulloides in its smaller size, by having up to 4½ chambers in the ultimate whorl and by having some morphotypes with a moderately elevated trochospire. It is distinguished from G. officinalis by lobed peripheral outline, and fully developed bulloides-type wall, especially on the final chamber. It is distinguished from Globoturborotalita ouachitaensis by the bulloides-type wall. [Spezzaferri et al. 2018]


Wall type: Normal perforate, spinose, bulloides-type wall structure. Pore concentrations range from 80 to 130 pores/50 mm2 test surface area and pore diameters range from 0.7 mm to 0.9 mm.

Test morphology: Test low to moderately elevated trochospiral consisting of 2½ whorls, lobulate in outline, chambers globular; in spiral view 4-4½ globular, slightly embracing chambers in ultimate whorl, increasing rapidly in size, final chamber varies in size and degree of inflation, sutures moderately depressed and straight; in umbilical view 4-4½ globular, slightly embracing chambers, increasing rapidly in size, sutures moderately depressed, straight, umbilicus large, open, enclosed by surrounding chambers, aperture umbilical, a broad arch bordered by an imperforate rim; in edge view chambers globular in shape, slightly embracing. [Spezzaferri et al. 2018]

Size: Maximum diameter of holotype 0.20 mm. [Spezzaferri et al. 2018]

Character matrix

test outline:Lobatechamber arrangement:Trochospiraledge view:Concavo-convexaperture:Umbilical
sp chamber shape:Globularcoiling axis:Low-moderateperiphery:N/Aaperture border:Thin lip
umb chbr shape:Globularumbilicus:Wideperiph margin shape:Broadly roundedaccessory apertures:None
spiral sutures:Moderately depressedumb depth:Deepwall texture:Cancellateshell porosity:Macroperforate: >2.5µm
umbilical or test sutures:Strongly depressedfinal-whorl chambers:4.0-4.5 N.B. These characters are used for advanced search. N/A - not applicable

Biogeography and Palaeobiology


Geographic distribution: Probably had a distribution similar to G. bulloides. Modern G. bulloides is a cosmopolitan species but it also occurs in cool upwelling regions. [Spezzaferri et al. 2018]

Isotope paleobiology: No data available. [Spezzaferri et al. 2018]

Phylogenetic relations: Globigerina archaeobulloides probably evolved from G. officinalis in Zone O1. It gave rise to Globigerinella obesa in Zone O1 and is thus ancestral to genus Globigerinella. It is also the direct ancestor of Globigerina bulloides, which appeared in Zone O5. [Spezzaferri et al. 2018]

Most likely ancestor: Globigerina officinalis - at confidence level 2 (out of 5). Data source: Spezzaferri et al. 2018.
Likely descendants: Globigerina bulloides; Globigerinella obesa;

Biostratigraphic distribution

Geological Range:
Notes: Lower Oligocene Zone O1 probably to the upper Oligocene where it gives rise to G. bulloides in Zone O5 (this study). [Spezzaferri et al. 2018]
Last occurrence (top): within O7 zone (22.96-25.21Ma, top in Aquitanian stage). Data source: Spezzaferri et al. 2018
First occurrence (base): within O1 zone (32.10-33.90Ma, base in Priabonian stage). Data source: Spezzaferri et al. 2018

Plot of occurrence data:

Primary source for this page: Spezzaferri et al. 2018 - Olig Atlas chap.6 p.183

References:

Olsson, R. K., Hemleben, C., Huber, B. T. & Berggren, W. A. (2006b). Taxonomy, biostratigraphy, and phylogeny of Eocene Globigerina, Globoturborotalita, Subbotina, and Turborotalita. 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 6): 111-168. gs

Spezzaferri, S., Coxall, H. K., Olsson, R. K. & Hemleben, C. (2018a). Taxonomy, biostratigraphy, and phylogeny of Oligocene Globigerina, Globigerinella, and Quiltyella n. gen. 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 6): 179-214. gs


logo

Globigerina archaeobulloides compiled by the pforams@mikrotax project team viewed: 24-10-2019

Taxon Search:
Advanced Search

Short stable page link: http://mikrotax.org/pforams/index.php?id=104319 Go to Archive.is to create a permanent copy of this page - citation notes



Comments (0)

No comments yet. Be the first!

Add Comment

* Required information
1000
Captcha Image
Powered by Commentics