pforams@mikrotax - Orbulina suturalis pforams@mikrotax - Orbulina suturalis

Orbulina suturalis

Classification: pf_cenozoic -> Globigerinidae -> Orbulina -> Orbulina suturalis
Sister taxa: O. universa, O. suturalis, O. sp.

3D models from The Foraminarium, hosted on sketchfab


Citation: Orbulina suturalis Brönnimann, 1951
taxonomic rank: species
Basionym: Orbulina suturalis
Taxonomic discussion: Orbulina suturalis is in our opinion to be understood as a short-lived species occurring in the middle Miocene (Wade et al. 2011) during a time when the diagnostic morphology of O. universa evolved (Pearson et al., 1997). Among living O. universa, forms similar to O. suturalis do occur but are rare and associated with an anomalously small spherical chamber relative to the enclosed “spiral” shell, or by the excentric envelopment of the sphere with respect to the spiral shell. [Brummer & Kucera 2022]

Catalog entries: Orbulina suturalis, Candorbulina universa

Type images:

Distinguishing features:
Parent taxon (Orbulina): Spherical terminal chamber:
This taxon: final chamber not entirely enveloping earlier test

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.


Adult test almost spherical, final chamber not entirely enveloping the early part of the test. Tests show all gradations from a partly enveloped Globigerina to an almost completely enveloped one. In the adult stage, the Globigerina chambers are visible only as low, rounded projections from a general sphere; surface densely perforate; aperture areal distributed over the surface of final chamber. Supplementary apertures along sutures separating the final and earlier chambers. [Kennett & Srinivasan 1983]

Wall type:
Spinose; Hispid [Aze 2011]

Character matrix
test outline:Circularchamber arrangement:Envelopingedge view:Equally biconvexaperture:Umbilical
sp chamber shape:Inflatedcoiling axis:Moderateperiphery:N/Aaperture border:N/A
umb chbr shape:Inflatedumbilicus:Wideperiph margin shape:Broadly roundedaccessory apertures:Sutural
spiral sutures:Flushumb depth:Deepwall texture:Cancellateshell porosity:Macroperforate: >2.5µm
umbilical or test sutures:Strongly depressedfinal-whorl chambers:1-3 N.B. These characters are used for advanced search. N/A - not applicable

Biogeography and Palaeobiology

Geographic distribution

Tropical to temperate. [Kennett & Srinivasan 1983] Low to middle latitudes [Aze et al. 2011, based on Kennett & Srinivasan (1983)]

[SCOR WG138]

Isotope paleobiology
Widely recorded as a photosymbiotic mixed-layer species but Aze et al. (2011) place it in ecogroup 3 - Open ocean thermocline. Based on light δ13C and relatively heavy δ18O. Sources cited by Aze et al. 2011 (appendix S3): D. R. M. Stewart unpublished data

Phylogenetic relations
O. suturalis is distinguished from Praeorbulina circularis, its immediate ancestor, by lacking the small apertures confined to the suture of the Globigerina stage and by the areal apertures over the surface. The initial evolutionary appearance of O. suturalis (Orbulina datum) has been recorded throughout the world and is taken to mark the base of the Middle Miocene. [Kennett & Srinivasan 1983]

Most likely ancestor: Praeorbulina circularis - at confidence level 4 (out of 5). Data source: Kennett & Srinivasan 1983, fig. 11.
Likely descendants: Orbulina universa; plot with descendants

Biostratigraphic distribution

Geological Range:
Last occurrence (top): within N21 zone (1.93-3.10Ma, top in Gelasian stage). Data source: Kennett & Srinivasan 1983
First occurrence (base): at base of M6 zone (0% up, 15.1Ma, in Langhian stage). Data source: Wade et al. (2011), zonal marker

Plot of occurrence data:

Primary source for this page: Kennett & Srinivasan 1983, p.86


Aze, T. et al. (2011). A phylogeny of Cenozoic macroperforate planktonic foraminifera from fossil data. Biological Reviews. 86: 900-927. gs

Brönnimann, P. (1951b). The genus Orbulina d'Orbigny in the Oligo-Miocene of Trinidad, B. W. I. Contributions from the Cushman Foundation for Foraminiferal Research. 2(4): 135+-. gs

Brummer, G-J. A. & Kucera, M. (2022). Taxonomic review of living planktonic foraminifera. Journal of Micropalaeontology. 41: 29-74. 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

Norris, R. D. (1998). Planktonic foraminifer biostratigraphy: Eastern Equatorial Atlantic. Proceedings of the Ocean Drilling Program, Scientific Results. 159: 445-479. gs O

Pearson, P. N., Shackleton, N. J. & Hall, M. A. (1997a). Stable isotopic evidence for the sympatric divergence of Globigerinoides trilobus and Orbulina universa (planktonic foraminifera). Journal of the Geological Society of London. 154: 295-302. gs

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

Wade, B. S., Pearson, P. N., Berggren, W. A. & Pälike, H. (2011). Review and revision of Cenozoic tropical planktonic foraminiferal biostratigraphy and calibration to the geomagnetic polarity and astronomical time scale. Earth-Science Reviews. 104: 111-142. gs


Orbulina suturalis compiled by the pforams@mikrotax project team viewed: 26-5-2024

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