Globigerinayeguaensis Weinzierl and Applin, 1929:409, pl. 43: fig. 1a-b [middle Eocene, Yegua Fm., subsurface, Louisiana].—Bolli, 1957:163 (partim; not pl. 35: fig. 14 a-c), pl. 35: fig. 15 a-c [middle Eocene Zone E14, Navet Fm., Trinidad].—Blow, 1969:319, pl. 3: figs. 12-14 (holotype reillustrated).—Saito, 1962:216 (partim), pl. 32: fig. 1a-c [middle Eocene Zone E12, Haha-Jima, Bonin Islands, western Pacific Ocean]. [Not pl. 32, figs. 2, 3.].— Samanta, 1970:192, pl. 1: figs. 15-17 [middle Eocene Zone E12, Lakhpat, Cutch, western India]._Blow, 1979:1313, pl. 3: figs. 12-14 (holotype reillustrated).—Bolli and Saunders, 1985:180, fig. 13-23a,b (holotype reillustrated).
Subbotina yeguaensis (Weinzierl and Applin).—Huber, 1991: 441, pl.5: fig. 2 [middle Eocene Zone AE3/4, ODP Site 738, Kerguelen Plateau, Southern Indian Ocean].— Nishi and Chaproniere, 1994:260, pl. 5: figs. 13-15 [upper Eocene Zone E14/15, ODP Hole 841B, Tonga Trench, Pacific Ocean]._Warraich and Ogasawara, 2001:49, fig. 14: 4, 8, 12 [Zone E10/11, Kirthar Fm., Sulaiman Range, Pakistan].
Globigerinapseudoeocaena Subbotina var. pseudoeocaena Subbotina 1953:81 (partim; not pl. 5: figs. 1a-2c = Subbotinaeocaena; not pl. 5: fig. 6a-c = Subbotinacorpulenta), pl. 4: fig. 9a-c, holotype, [lower-middle Eocene Zone of conical Globorotalia, Kuban River, northern Caucasus].
Globigerinalinapertapseudoeocaena (Subbotina)._Blow and Banner, 1962:87, pl. 11, fig. M [upper Eocene Cribrohantkeninadanvillensis Zone, Lindi area, Tanzania].
Subbotina pseudoeocaena (Subbotina)._Blow, 1979:1279, pl. 187: figs. 8, 9 [Zone E10/11, DSDP Site 19, South Atlantic Ocean].—Belford, 1984:14 (partim; not pl. 23: figs. 19-21), pl. 23: figs. 16-18 [middle Eocene, Papua, New Guinea].
Globigerinapseudoeocaena Subbotina.—Krasheninnikov and Basov, 1983: 838, pl. 2: figs. 1-3 [middle Eocene DSDP Site 512, Maurice Ewing Bank, South Atlantic Ocean].
?Globigerinapseudoeocaena var. ellipsocamerata Khalilov, 1956:241, pl. 3: fig 1a-c [middle Eocene, Maly Caucasus].
Subbotinaangiporoideslindiensis Blow, 1979:1253, pl. 244: figs. 8-9 [upper Eocene Zone E15/16, Lindi, Tanzania].
Taxonomic discussion: Blow (1979) included Subbotinayeguaensis in his new genus Dentoglobigerina, believing that it was an intermediate species between D. galavisi (Bermúdez) and D. pseudovenezuelana (Blow and Banner). This was apparently based on his concept of a “central type” for D. galavisi, which are forms from the middle Eocene. However, these forms do not fit the central morphology of D. galavisi which was described from the upper Eocene Jackson Formation, Mississippi, which spans from Zones E15-16 (see holotype Pl. 13.1, Figs. 1-3, this volume and discussion under D. galavisi). Subbotina yeguaensis is spinose and lacks the triangular lip that characterizes the nonspinose genus Dentoglobigerina and, therefore, cannot be placed as an intermediate species in a Dentoglobigerina lineage. Subbotinayeguaensis was described from the middle Eocene subsurface of Louisiana where it is common. The holotype of Subbotinapseudoeocaena (Subbotina) which is described from the lower/middle Eocene of the northern Caucasus has the morphologic characteristics of S. yeguaensis and is considered a junior synonym (see Pl. 6.18, Figs. 13-15), as is Subbotinaangiporoideslindiensis of Blow (1979) and possibly Globigerinapseudoeocaena Subbotina var. ellipsocamerata Khalilov (1956; viewed by WAB). [Olsson et al. 2006]
Distinguishing features: Parent taxon (Subbotina): Low trochospiral, tripartite test, with 3-4 rapidly inflating, globular chambers in final whorl.
Umbilicus nearly closed by tight coiling.
Wall cancellate with spines at nodes of the ridges, +/- spine collars. This taxon: Test lobulate, moderately elevated trochospire. Aperture with somewhat broad lip that tapers both anteriorly and posteriorly.
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: The species is characterized by its lobulate test and moderately elevated trochospire, and the somewhat broad apertural lip that tapers both anteriorly and posteriorly. [Olsson et al. 2006] Morphology: Test moderately elevated, trochospiral, globular, lobulate in outline, chambers globular; in spiral view 3 1/3 globular, slightly embracing chambers in ultimate whorl, increasing moderately in size, ultimate chamber may be equal to or smaller in size than penultimate chamber, sutures moderately depressed, straight; in umbilical view 3 1/3 globular, slightly embracing chambers, increasing moderately in size, sutures moderately depressed, straight, umbilicus small, enclosed by surrounding chambers, aperture umbilical, bordered by a somewhat broad lip that tapers both anteriorly and posteriorly, ultimate chamber may be equal to or smaller than the penultimate chamber; in edge view moderately elevated trochospire, chambers globular in shape, somewhate embracing, aperture visible as a low rounded opening, bordered by a somewhat broad lip. [Olsson et al. 2006] Wall type: Normal perforate, symmetrically cancellate, sacculifer-type wall texture, spinose. [Olsson et al. 2006] Size: Maximum diameter of holotype 0.52 mm, thickness 0.40 mm. [Olsson et al. 2006]
Character matrix
test outline:
Lobate
chamber arrangement:
Trochospiral
edge view:
Equally biconvex
aperture:
Umbilical
sp chamber shape:
Globular
coiling axis:
Moderate-high
periphery:
N/A
aperture border:
Thick lip
umb chbr shape:
Globular
umbilicus:
Narrow
periph margin shape:
Broadly rounded
accessory apertures:
None
spiral sutures:
Moderately depressed
umb depth:
Deep
wall texture:
Cancellate
shell porosity:
Finely Perforate: 1-2.5µm
umbilical or test sutures:
Moderately depressed
final-whorl chambers:
3-3
N.B. These characters are used for advanced search. N/A - not applicable
Biogeography and Palaeobiology
Geographic distributionGlobal in low to high latitudes. [Olsson et al. 2006]
Aze et al. 2011 summary: Cosmopolitan; based on Olsson et al. (2006a) Isotope paleobiologyBoersma and others (1987) record strongly positive δ18O for this species indicating a deep planktonic habitat. [Olsson et al. 2006] Aze et al. 2011 ecogroup 4 - Open ocean sub-thermocline. Based on very light _13C and very heavy _18O. Sources cited by Aze et al. 2011 (appendix S3): Boersma et al. (1987); Coxall et al. (2000) Phylogenetic relationsSubbotinayeguaensis belongs to a group of subbotinids with symmetrical cancellate (sacculifer-type) wall texture. It apparently arose in the early Eocene, possibly from S. eocaena. [Olsson et al. 2006]
Geological Range: Notes: Zone E7 to Zone E16. [Olsson et al. 2006] Last occurrence (top): within E16 zone (33.90-34.68Ma, top in Priabonian stage). Data source: Eocene Atlas First occurrence (base): within E7 zone (45.72-50.20Ma, base in Ypresian stage). Data source: Eocene Atlas
Plot of occurrence data:
Range-bar - range as quoted above, pink interval top occurs in, green interval base occurs in.
Triangles indicate an event for which a precise placement has been suggested.
Grey shading between taxa indicates intergrading species within an anagenetic lineage (data from
Lamyman et al. 2026).
Histogram - Neptune occurrence data from DSDP and ODP proceedings. Pale shading <50 samples in time bin. Interpret with caution & read these notes
Primary source for this page: Olsson et al. 2006 - Eocene Atlas, chap. 6, p. 162
References:
Belford, D. J. (1984). Tertiary foraminifera and age of sediments, Ok Tedi-Wabag, Papua New Guinea. Australia Bureau of Mineral Resources Geology and Geophysics, Bulletin. 216: 1-52. gs
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
Blow, W. H. (1969). Late middle Eocene to Recent planktonic foraminiferal biostratigraphy. In, Bronnimann, P. & Renz, H. H. (eds) Proceedings of the First International Conference on Planktonic Microfossils, Geneva, 1967. E J Brill, Leiden 380-381. gs
Blow, W. H. (1979). The Cainozoic Globigerinida: A study of the morphology, taxonomy, evolutionary relationships and stratigraphical distribution of some Globigerinida (mainly Globigerinacea). E. J. Brill, Leiden. 2: 1-1413. gs
Bolli, H. M. & Saunders, J. B. (1985). Oligocene to Holocene low latitude planktic foraminifera. In, Bolli, H. M., Saunders, J. B. & Perch-Neilsen, K. (eds) Plankton Stratigraphy. Cambridge University Press, Cambridge, UK 155-262. gs
Bolli, H. M. (1957a). Planktonic foraminifera from the Eocene Navet and San Fernando formations of Trinidad. 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: 155-172. gs
Huber, B. T. (1991c). Paleogene and Early Neogene Planktonic Foraminifer Biostratigraphy of Sites 738 and 744, Kerguelen Plateau (Southern Indian Ocean). Proceedings of the Ocean Drilling Program, Scientific Results. 119: 427-449. gs
Khalilov, D. M. (1956). 0 pelagicheskoy faune foraminifer Paleogenovykh otlozheniy Azerbaydzhana [Pelagic Foraminifera of the Paleogene Deposits of the Azerbaizhan SSR]. Trudy Instituta Geologii, Akademiya Nauk Azerbaidzhanskoi SSR. 17: 234-255. gs
Krasheninnikov, V. A. & Basov, I. A. (1983). Stratigraphy of Cretaceous sediments of the Falkland Plateau based on planktonic foraminifers, Deep Sea Drilling Project, Leg 71. Initial Reports of the Deep Sea Drilling Project. 71: 789-820. gs
Nishi, H. & Chaproniere, G. C. H. (1994). Eocene-Oligocene subtropical planktonic foraminifers at Site 841,. Proceedings of the Ocean Drilling Program, Scientific Results. 135: 245-266. 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. gsO
Postuma, J. A. (1971). Manual of planktonic foraminifera. Elsevier for Shell Group, The Hague. 1-406. gs
Saito, T. (1962a). Eocene planktonic foraminifera from Hahajima (Hillsborough Island). Transactions and Proceedings of the Palaeontological Society of Japan. 45: 209-225. gs
Warraich, M. Y. & Ogasawara, K. (2001). Tethyan Paleocene-Eocene planktic foraminifera from the Rakhi Nala and Zinda Pir land sections of the Sulaiman Range, Pakistan. Science Reports of the Institute of Geosciences, University of Tsukuba. 22: 1-59. gs
Weinzierl, L. L. & Applin, E. R. (1929). The Claiborne Formation on the Coastal Domes. Journal of Paleontology. 3(4): 384-410. gs
Subbotina yeguaensis compiled by the pforams@mikrotax project teamviewed: 21-7-2026
Eocene_Atlas_pl06-18_fig8-10.jpg
Eocene_Atlas_pl06-18_fig4-6.jpg
Eocene_Atlas_pl06-18_fig12.jpg
Postuma 1971 p163-4.JPG
Postuma 1971 p163-7.JPG
Eocene_Atlas_pl06-18_fig8-10.jpg
Eocene_Atlas_pl06-18_fig4-6.jpg
Eocene_Atlas_pl06-18_fig12.jpg
Postuma 1971 p163-4.JPG
Postuma 1971 p163-7.JPG
holotype: G. yeguaensis
holotype: G. yeguaensis
