pforams@mikrotax - Globigerinella obesa

Citation: Globigerinella obesa (Bolli, 1957)

Basionym: Globorotalia obesa Bolli, 1957

Synonyms:

Globorotalia obesa Bolli, 1957:119, pl. 29, figs. 2a-3 [middle Miocene Globorotalia fohsi robusta Zone, Cipero Fm., Trinidad].—Stainforth and others, 1975:297, fig. 130 [middle Miocene, Cipero Fm., Trinidad and Pozón Fm., Venezuela].—Molina, 1979:231, pl. 32, figs. 1A-C [lower Miocene, Cordilleras Beticas, Spain].—Kennett and Srinivasan, 1983:234, pl. 59, figs. 2–5 [lower Pliocene Globorotalia puncticulata Zone, DSDP Site 281, South Tasman Rise].
Globorotalia (Turborotalia) obesa Bolli.—Jenkins, 1971:127, pl. 13, figs. 348-350 [lower Miocene, Parengarenga Harbour section, New Zealand].
Globigerinella obesa (Bolli).—Kennett and Srinivasan, 1983:234, pl. 59, figs. 2-5 [early Pliocene Globorotalia puncticulata Zone, DSDP Site 281, South Tasman Rise, Tasman Sea].—Spezzaferri and Premoli Silva, 1991:251, pl. XI, figs. 3a-c [upper Oligocene Zone P22 (= O7), DSDP Hole 538A, Gulf of Mexico].—Spezzaferri, 1994:50, pl.17, figs. 5a-c [upper Oligocene Zone P22 (= O7), ODP Hole 709B, Indian Ocean].—Pearson and Wade, 2009:206, pl. 4, figs. 5a-d [upper Oligocene Zone O6 (= Zone O7), Cipero Fm., Trinidad].—Beldean and others, 2012:178, pl. 1, fig. 10 [lower Miocene Zones NN1 and NN2, Hida Fm., northwest Transylvanian Basin].
Globigerina praebulloides Blow, 1959: pl. 8, figs. 47a-c, holotype [lower Miocene Globigerinatella insueta/Globigerinoides bisphericus Zone, Pozón Fm., Venezuela].

Taxonomic discussion:

Globigerinella obesa was initially included in the genus Globorotalia. It is now recognized as the first species of Globigerinella. SEMs of the holotype of Blow’s Globigerina praebulloides and the paratype USNM 625702A show that they have a bulloides-type wall texture, but chamber architecture very similar to G. obesa, e.g., umbilical-extraumbilical primary aperture therefore, praebulloides is here considered a junior synonym of Globigerinella obesa Bolli (Pl. 6.8, Figs. 4-6). [Spezzaferri et al. 2018]

Distinguishing features:
Parent taxon (Globigerinella): Test initially trochospiral, becoming nearly planispiral; globular to ovate chambers; aperture umbilical; fine spines cover the test
This taxon: Low trochospiral lobulate test, 4 chambers in the last whorl, extraumbilical to equatorial aperture; bulloides-type wall texture.

Description

Globigerinella obesa is characterized by low trochospiral lobulate test, 4 chambers in the last whorl, extraumbilical to equatorial aperture and a bulloides-type wall texture. It differs from G. archaeobulloides, from which it evolved, and G. bulloides by having an umbilical-extraumbilical aperture tending toward the peripheral margin and a somewhat inflated final chamber. It differs from G. praesiphonifera by the more enrolled coiling, having 4 chambers in the last whorl instead of 5 in G. praesiphonifera, lesser tendency towards planispirality and a less lobulate outline. [Spezzaferri et al. 2018]

Test very low trochospiral, consisting of 2-2½ whorls, lobulate in outline, chambers globular; in spiral view 4 globular, slightly embracing chambers in ultimate whorl, increasing rapidly in size, sutures moderately depressed, straight; in umbilical view 4 globular, slightly embracing chambers, increasing rapidly in size, sutures moderately depressed, straight, umbilicus small, open, enclosed by surrounding chambers, aperture umbilical-extraumbilical, a low arch sometimes bordered by an imperforate rim; in edge view chambers globular in shape, slightly embracing. [Spezzaferri et al. 2018]

Spinose, spines are supported by spine collars which coalesce to form ridges. Pore concentrations average 62 pores/50 μm2 test surface area and pore diameters average 2.5 μm.

Maximum diameter of holotype 0.5 mm. [Spezzaferri et al. 2018]

Biogeography and Palaeobiology

Identified in low to middle latitudes. [Spezzaferri et al. 2018]

No data available. [Spezzaferri et al. 2018]

Globigerinella obesa evolved from Globigerina archaeobulloides n. sp. in the lower Oligocene Zone O1 and gave rise to G. praesiphonifera in the mid-Oligocene Zone O4. [Spezzaferri et al. 2018]

Biostratigraphic distribution

Geological Range:
Notes: Lower Oligocene Zone O1 (Plate 6.1, Figs. 14-17) to the lower Pliocene (Kennett and Srinivasan, 1983). [Spezzaferri et al. 2018]. NB Kennett & Srinivasan (1983) record the range as extending to the recent but the specimen they illustrate is from the Early Pliocene. [editor's comment - JRY 2018]
Last occurrence (top): within Early Pliocene Sub-Epoch (3.60-5.33Ma, top in Zanclean 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

Primary source for this page: Spezzaferri et al. 2018 - Olig Atlas chap.6 p.198

References:

Beldean, C., Filipescu, S. & Bălc, R. (2012). P and biostratigraphic data for the early Miocene of the north-western Transylvanian basin based on planktoqnic foraminifera. Carpathian Journal of Earth and Environmental Sciences. 7: 171-184. gs

Berggren, W. A., Pearson, P. N., Huber, B. T. & Wade, B. S. (2006b). Taxonomy, biostratigraphy, and phylogeny of Eocene Acarinina. 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 9): 257-326. gs O

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

Bolli, H. M. (1957b). Planktonic foraminifera from the Oligocene-Miocene Cipero and Lengua formations of Trinidad, B.W.I. In, Loeblich, A. R. , Jr., Tappan, H., Beckmann, J. P., Bolli, H. M., Montanaro Gallitelli & E. Troelsen, J. C. (eds) Studies in Foraminifera. U.S. National Museum Bulletin . 215: 97-123. gs

Coxall, H. K. & Pearson, P. N. (2006). Taxonomy, biostratigraphy, and phylogeny of the Hantkeninidae (Clavigerinella, Hantkenina and Cribrohantkenina). 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 8): 213-256. gs O

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

Lam, A. & Leckie, R. M. (2020a). Late Neogene and Quaternary diversity and taxonomy of subtropical to temperate planktic foraminifera across the Kuroshio Current Extension, northwest Pacific Ocean. Micropaleontology. 66(3): 177-268. gs

Molina, E. (1979). Oligoceno-Mioceno inferior por media de foraminiferos planctonicos en el sector central de las Cordilleraa Beticas Espana (Tesis doctoral). . 1-342. gs

Olsson, R. K., Hemleben, C., Huber, B. T. & Berggren, W. A. (2006a). 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 O

Pearson, P. N. & Wade, B. S. (2009). Taxonomy and stable isotope paleoecology of well-preserved planktonic foraminifera from the uppermost Oligocene of Trinidad. Journal of Foraminiferal Research. 39: 191-217. gs

Postuma, J. A. (1971). Manual of planktonic foraminifera. Elsevier for Shell Group, The Hague. 1-406. gs

Spezzaferri, S. & Premoli Silva, I. (1991). Oligocene planktonic foraminiferal biostratigraphy and paleoclimatic interpretation from Hole 538A, DSDP Leg 77, Gulf of Mexico. Palaeogeography Palaeoclimatology Palaeoecology. 83: 217-263. 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., 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

Stainforth, R. M., Lamb, J. L., Luterbacher, H., Beard, J. H. & Jeffords, R. M. (1975). Cenozoic planktonic foraminiferal zonation and characteristics of index forms. University of Kansas Paleontological Contributions, Articles. 62: 1-425. gs O

test outline:	Lobate	chamber arrangement:	Pseudoplanispiral	edge view:	Equally biconvex	aperture:	Umbilical-extraumbilical
sp chamber shape:	Globular	coiling axis:	Very low	periphery:	N/A	aperture border:	Thin lip
umb chbr shape:	Globular	umbilicus:	Wide	periph margin shape:	Broadly rounded	accessory apertures:	None
spiral sutures:	Strongly depressed	umb depth:	Deep	wall texture:	Cancellate	shell porosity:	Macroperforate: >2.5µm
umbilical or test sutures:	Strongly depressed	final-whorl chambers:	4-4	N.B. These characters are used for advanced search. N/A - not applicable

Globigerinella obesa

Taxonomy

Description

Biogeography and Palaeobiology

Biostratigraphic distribution

References:

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