Globorotaloides quadrocameratus


Classification: pf_cenozoic -> Globigerinidae -> Globorotaloides -> Globorotaloides quadrocameratus
Sister taxa: G. atlanticus, G. stainforthi, G. eovariabilis, G. hexagonus, G. quadrocameratus, G. suteri, G. testarugosus, G. variabilis, G. sp.,

Taxonomy

Citation: Globorotaloides quadrocameratus Olsson, Pearson & Huber 2006
Rank: Species
Basionym: Globorotaloides quadrocameratus
Synonyms:
Taxonomic discussion:

Globorotaloides quadrocameratus is a distinctly lobate species of Globorotaloides. It intergrades with Globorotaloides suteri (Pl. 4.7, Figs. 5-8), to which it gave rise in the middle Eocene (see Catapsydrax unicavus and Globorotaloides suteri entries for history of synonymy). Globorotaloides quadrocameratus lacks a bulla. It is less common in the Oligocene than the Eocene. The relationship of Blow and Banner’s (1962) taxon Globorotalia (Turborotalia) permicra, here shown as a questionable prior synonym of G. quadrocameratus, is discussed in Pearson and Wade (2015), who conclude it is likely a juvenile and discourage its use. [Coxall & Spezzaferri 2018]

Catalog entries: Globorotaloides quadrocameratus;

Type images:

Distinguishing features: Test, small, lobulate test, 4-4½ chambers in final whorl, final chamber directed umbilically. Sacculifer-type wall texture.

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:

Globorotaloides quadrocameratus is characterized by its small, distinctly lobulate test, 4 chambers in the ultimate whorl, the umbilically directed ultimate chamber and rapidly enlarging final whorl chambers. It differs from Parasubbotina varianta and Paragloborotalia griffinoides by the smaller size, more coarsely cancellate test, more open coiling and flattened spiral side. It differs from Globorotaloides suteri in the more open coiling and more rapidly enlarging chambers and from Catapsydrax unicavus in the greater number of final whorl chambers and umbilical-extraumbilical position of the aperture and lack of a bulla. Globorotalia (Turborotalia) permicra Blow and Banner is a juvenile form that is probably conspecific with quadrocameratus (see Pearson and Wade, 2015, for discussion). [Coxall & Spezzaferri 2018]


Wall type: Spinose (?). Normal perforate, coarsely cancellate, sacculifer-type, wall structure. [Coxall & Spezzaferri 2018]

Test morphology: Test very low trochospiral, 2-2½ whorls, lobate in outline, chambers globular; in spiral view 4 globular, slightly embracing chambers in the ultimate whorl, increasing rapidly in size, sutures moderately depressed, straight; in umbilical view 4 globular, slightly embracing chambers, increasing rapidly in size, ultimate chamber may be directed towards the umbilicus, sutures moderately depressed, straight, umbilicus small, aperture umbilical-extraumbilical a low opening bordered by narrow thickened lip; in edge view chambers globular in shape, slightly embracing (modified from Olsson and others, 2006a). [Coxall & Spezzaferri 2018]

Size: Maximum diameter of holotype 0.18 mm, breadth 0.10 mm. [Coxall & Spezzaferri 2018]

Character matrix

test outline:Lobatechamber arrangement:Trochospiraledge view:Equally biconvexaperture:Umbilical-extraumbilical
sp chamber shape:Globularcoiling axis:Lowperiphery:N/Aaperture border:Thin lip
umb chbr shape:Globularumbilicus:Narrowperiph margin shape:Broadly roundedaccessory apertures:N/A
spiral sutures:Weakly depressedumb depth:Shallowwall texture:Cancellateshell porosity:Macroperforate: >2.5µm
umbilical or test sutures:Moderately 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: Global, including low and mid-latitudes. Can be common in southern and northern high latitudes. Possible affinity with high productivity conditions. [Coxall & Spezzaferri 2018]

Isotope paleobiology: Stable isotopes suggest that Globorotaloides quadrocameratus occupied a sub-thermocline planktonic habitat similar to Catapsydrax (Coxall, unpublished data). [Coxall & Spezzaferri 2018]

Phylogenetic relations: The origin of Globorotaloides quadrocameratus, and therefore the genus, is uncertain. In their original description of G. quadrocameratus, Olsson and others (2006a) suggested that it evolved in the basal Eocene from Parasubbotina varianta by flattening of the coil and development of a coarsely cancellate wall. In our current analysis we find similarities between G. quadrocameratus and early Paleocene forms referred to Subbotina cancellata (see Olsson and others, 1999; pl. 9, figs. 7-9, pl. 25, fig. 7). In particular we see a strong resemblance between quadrocameratus and the holotype of ‘Globigerina fringa Subbotina, 1953’ (Olsson and others, 1999:29, pl. 9, figs. 7-9), which is quadrate, highly cancellate and laterally flattened. We therefore suggest that the ancestry of Globorotaloides lies in the Danian, and that Globigerina fringa is a questionable prior synonym of G. quadrocameratus. This requires further research that is beyond the scope of this study.

Globorotaloides quadrocameratus is closely allied to G. eovariabilis, with which it commonly occurs. The smooth/flattened inner whorl as seen in spiral view, is common to both taxa. Globorotaloides quadrocameratus gave rise to Globorotaloides eovariabilis. [Coxall & Spezzaferri 2018]

Most likely ancestor: Parasubbotina varianta - at confidence level 1 (out of 5). Data source: Olsson et al. 2006. p83 (tentative suggestion)..
Likely descendants: Catapsydrax unicavus; Globorotaloides eovariabilis; Globorotaloides suteri;

Biostratigraphic distribution

Geological Range:
Notes: Lower Eocene Zone E2 (Olsson and others, 2006a) to lower Miocene Zone M1 (upper range constrained in this study, see figured specimens and their horizons, pl. 4.7). [Coxall & Spezzaferri 2018]
Last occurrence (top): within M1 zone (21.12-22.96Ma, top in Aquitanian stage). Data source: Coxall & Spezzaferri 2018
First occurrence (base): within E2 zone (55.20-55.81Ma, base in Ypresian stage). Data source: Olsson et al. 2006

Plot of occurrence data:

Primary source for this page: Coxall & Spezzaferri 2018 - Olig Atlas chap.4 p.101; Olsson et al. 2006 - Eocene Atlas, chap. 5, p. 83

References:

Blow, W. H. & Banner, F. T. (1962). The mid-Tertiary (Upper Eocene to Aquitanian) Globigerinaceae. In, Eames, F. E. , Banner, F. T. , Blow, W. H. & Clarke, W. J. (eds) Fundamentals of mid-Tertiary Stratigraphical Correlation. Cambridge University Press, Cambridge 61-151. 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. & Spezzaferri, S. (2018). Taxonomy, biostratigraphy, and phylogeny of Oligocene Catapsydrax, Globorotaloides, and Protentelloides. 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: 79-125. gs

McKeel, D. R. & Lipps, J. H. (1972). Calcareous plankton from the Tertiary of Oregon. Palaeogeography, Palaeoclimatology, Palaeoecology. 12(01-Feb): 75-93. gs

Olsson, R. K., Hemleben, C., Berggren, W. A. & Huber, B. T. (1999). Atlas of Paleocene Planktonic Foraminifera. Smithsonian Institution Press, Washington, DC. 1-252. gs

Olsson, R. K., Pearson, P. N. & Huber, B. T. (2006c). Taxonomy, biostratigraphy, and phylogeny of Eocene Catapsydrax, Globorotaloides, Guembelitrioides, Paragloborotalia, Parasubbotina, and Pseudoglobigerinella n. gen. 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: 67-110. gs

Pearson, P. N. & Wade, B. S. (2015). Systematic taxonomy of exceptionally well-preserved planktonic foraminifera from the Eocene/Oligocene boundary of Tanzania. Cushman Foundation for Foraminiferal Research, Special Publication. 45: 1-85. gs

Poore, R. Z. & Brabb, E. E. (1977). Eocene and Oligocene planktonic foraminifera from the Upper Butano sandstone and type San Lorenzo formation, Santa Cruz Mountains, California. Journal of Foraminiferal Research. 7(4): 249-272. gs

Subbotina, N. N. (1953). Foraminiferes fossiles d'URSS Globigerinidae, Globorotaliidae, Hantkeninidae. Bureau de Recherches Geologiques et Minieres. 2239: 1-144. gs


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Globorotaloides quadrocameratus compiled by the pforams@mikrotax project team viewed: 26-6-2019

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