Globoturborotalita pseudopraebulloides


Classification: pf_cenozoic -> Globigerinidae -> Globoturborotalita -> Globoturborotalita pseudopraebulloides
Sister taxa: G. tenella, G. rubescens, G. decoraperta, G. apertura, G. connecta, G. druryi, G. nepenthes, G. woodi, G. cancellata, G. occlusa, G. paracancellata, G. pseudopraebulloides, G. barbula, G. bassriverensis, G. brazieri, G. eolabiacrassata, G. euapertura, G. gnaucki, G. labiacrassata, G. martini, G. ouachitaensis, G. sp.,

Taxonomy

Citation: Globoturborotalita pseudopraebulloides Olsson and Hemleben, in Spezzaferri et al. 2018
Rank: species
Synonyms:
Taxonomic discussion:

Blow’s species Globigerina praebulloides has been used by many workers to represent forms resembling Globigerina bulloides and considered to be early representatives of the bulloides lineage. SEM images of the holotype of praebulloides reveal a bulloides-type wall texture (Plate 6.8, Figs. 4-6, Chapter 6, this volume), however, the morphology is of a globigerinellid, i.e. evolute coiling and an extraumbilical aperture, and it is regarded as a junior synonym of Globigerinella obesa Bolli, therefore invalidating the name. In contrast, the majority of forms identified as G. praebulloides have a lobulate bulloides test morphology but lack the bulloides-type wall texture, having instead a much lower pore density and a significantly larger pore diameter than in G. bulloides. These wall textures can be attributed to the ruber/sacculifer-type. Globoturborotalita pseudopraebulloides n. sp., described herein is designed to carry this praebulloides ‘ideotype’. Globigerina bulloides s.s. appears in the upper Oligocene (Chapter 6, this volume) and overlaps in range with G. pseudopraebulloides. The bulloides-type wall texture can be traced to the lower Oligocene Zone O1 showing that the two species have separate unrelated lineages (see Chapter 6, this volume for further discussion). [Spezzaferri et al. 2018]

Catalog entries: Globoturborotalita pseudopraebulloides

Type images:

Distinguishing features:

Lobulate test with 4 rapidly enlarging chambers in final whorl, large open umbilicus, and umbilical aperture. Like G. occlusa but higher aperture and less embracing chambers

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:

Identified by its lobulate test with 4 rapidly enlarging chambers in ultimate whorl, large open umbilicus, and umbilical aperture. Globoturborotalita pseudopraebulloides is distinguished from G. paracancellata by having 4 complete chambers in the ultimate whorl, more evolute coiling, and a more open umbilicus. Globigerina leroyi Blow and Banner differs by having a bulloides-type wall texture, 3½ chambers in the ultimate whorl, a slower rate of chamber size increase, and smaller pore diameters. The low porosity ruber/sacculifer-type wall distinguishes G. pseudopraebulloides from other morphologically similar species with bulloides-type wall texture, such as Globigerina archaeobulloides n. sp., and G. bulloides. [Spezzaferri et al. 2018]


Wall type: Normal perforate, spinose, ruber/sacculifer-type wall texture, an average of 30 pores/50 μm2 test surface area.

Test morphology: Low trochospiral, consisting of 3 whorls, lobulate in outline, chambers globular; in spiral view 4 slightly embracing chambers in ultimate whorl, increasing rapidly in size, sutures depressed, straight; in umbilical view 4 slightly embracing chambers, increasing rapidly in size, sutures depressed, straight, umbilicus large, open, enclosed by surrounding chambers, aperture umbilical, a rounded arch, a very thin rim may be present; in edge view slightly embracing, initial whorl of chambers slightly elevated. [Spezzaferri et al. 2018]

Size: Maximum diameter of holotype 0.28 mm, minimum diameter 0.26 mm, maximum width 0.20 mm. [Spezzaferri et al. 2018]

Character matrix

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

Biogeography and Palaeobiology


Geographic distribution: Widespread in low and middle latitudes. Also occurs in the high latitude North Atlantic Ocean (ODP Site 647) during the lower Oligocene (this study). [Spezzaferri et al. 2018]

Isotope paleobiology: Specimens identified as Globigerina cf. bulloides (here placed in Globoturborotalita pseudopraebulloides n. sp., Pl. 8.13, Figs. 9-11) from the Cipero Formation, Trinidad gave δ18O and δ13C values indicative of a mixed-layer habitat (Pearson and Wade, 2009). [Spezzaferri et al. 2018]

Phylogenetic relations: Probably evolved from Globoturborotalita occulusa in the early Oligocene. [Spezzaferri et al. 2018]

Most likely ancestor: Globoturborotalita occlusa - at confidence level 3 (out of 5). Data source: Spezzaferri et al. 2018.

Biostratigraphic distribution

Geological Range:
Notes: Lower Oligocene Zone O2 to middle Miocene Zone M6 (Kennett and Srinivasan, 1983, Spezzaferri, 1994). [Spezzaferri et al. 2018]
Last occurrence (top): within M6 zone (14.24-15.10Ma, top in Langhian stage). Data source: Spezzaferri et al. 2018
First occurrence (base): within O2 zone (30.28-32.10Ma, base in Rupelian stage). Data source: Spezzaferri et al. 2018

Plot of occurrence data:

Primary source for this page: Spezzaferri et al. 2018 - Olig Atlas chap.8 p.260

References:

Chaproniere, G. C. H. (1980). Influence of plate tectonics on the distribution of late Palaeogene to early Neogene larger foraminiferids in the Australasian region. Palaeogeography, Palaeoclimatology, Palaeoecology. 31: 299-317. gs

Kennett, J. P. & Srinivasan, M. S. (1983). Neogene Planktonic Foraminifera. Hutchinson Ross Publishing Co., Stroudsburg, Pennsylvania. 1-265. gs

Li, Q. & McGowran, B. (2000). Miocene foraminifera from Lakes Entrance Oil Shaft, Gippsland, southeastern Australia. Association of Australasian Palaentologists Memoirs, Geological Society of Australia. 22: 1-142. gs

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

Rögl, F. (1969a). Die Foraminiferenfauna aus den Phosphoritsanden von Plesching bei Linz (Oberosterreich) - Ottnangien (Untermiozan). Sonderdruck aus Mitteilungen der Geologischen Gessellschaft in Wien. 213-234. 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., Olsson, R. K., Hemleben, C., Wade, B. S. & Coxall, H. K. (2018c). 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


logo

Globoturborotalita pseudopraebulloides compiled by the pforams@mikrotax project team viewed: 17-10-2019

Taxon Search:
Advanced Search

Short stable page link: http://mikrotax.org/pforams/index.php?id=104325 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