Globigerinafrontosa Subbotina, 1953:84 (partim, not holotype), pl. 12: figs. 5a-c (paratype) [upper Eocene, Foraminiferal Layer, Green Series, Acarinina Zone (upper part), Kuban River, N. Caucasus]. [Not Subbotina, 1953.]
Globorotaliacerroazulensis possagnoensis Toumarkine and Bolli, 1970:139, pl. 1: fig. 4 [middle Eocene, Possagno area, northern Italy].—Toumarkine, 1975:744, pl. 2: figs. 2, 3 [middle Eocene Globorotalialehneri Zone, DSDP Site 305, northwest Pacific Ocean].
Turborotaliacerrozulensis possagnoensis (Toumarkine and Bolli).—Toumarkine and Luterbacher, 1985:137, figs. 34.10-15 (re-illustrations from the literature).
Turborotaliapossagnoensis (Toumarkine and Bolli).—Poag and Commeau, 1995:pl. 4: fig. 20-21 [Eocene, Salisbury Embayment, Virginia].
Not Turborotaliapossagnoensis (Toumarkine and Bolli).— Poore and Bybell, 1988:21, pl. 2: figs. 4-7 [Middle Eocene, Core ACGS#4, New Jersey]. [ =Turborotaliapomeroli.]
Taxonomic discussion: This species was originally described as an evolutionary intermediate between T. frontosa (which has been regarded by some as a subbotinid) and the undisputed turborotaliid species, T. pomeroli. In our experience the morphospecies is quite rare in open ocean settings, although common in specimens from the Possagno area, where unfortunately the material is poorly preserved. We have, however, found well-preserved and closely comparable populations in wells from the Adriatic Sea. We regard possagnoensis as a relatively short-lived offshoot from T. frontosa, rather than an evolutionary intermediate to pomeroli as suggested by Toumarkine and Bolli (1970). [Pearson et al. 2006]
Distinguishing features: Parent taxon (Turborotalia): Trochospiral with umbilical-extraumbilical aperture.
Wall smooth pustulose, can be weakly cancellate, & may defoliate. This taxon: Like T. frontosa but flatter final chamber, giving test a quadrangular shape, also wall more finely perforate, & usually 3 chambers in the final whorl.
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
Morphology: Trochospiral, compressed with 3 (rarely 3.5) chambers in the final whorl; chambers inflated, strongly radially compressed and appressed, increasing moderately rapidly in size; dorsal sutures straight or slightly curved, depressed; aperture a broad, low arch in intra-extraumbilical position, sometimes with a thin imperforate lip; umbilicus generally narrow; ventral sutures slightly curved, depressed; strong tendency for dextral coiling.[Pearson et al. 2006] Wall type: Weakly cancellate in earlier chambers, becoming smoother with cylindrical pustules in later chambers; tendency to defoliate. Size: Holotype length 0.38 mm, breadth 0.31 mm. [Pearson et al. 2006]
Character matrix
test outline:
Lobate
chamber arrangement:
Trochospiral
edge view:
Inequally biconvex
aperture:
Umbilical
sp chamber shape:
Globular
coiling axis:
Low
periphery:
N/A
aperture border:
Thin 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:
3-3.5
N.B. These characters are used for advanced search. N/A - not applicable
Biogeography and Palaeobiology
Geographic distributionCosmopolitan; possibly most common in northern mid-latitudes. [Pearson et al. 2006]
Aze et al. 2011 summary: Cosmopolitan; based on Pearson et al. (2006) Isotope paleobiologyPoore and Matthews (1984) recorded this species as having relatively negative oxygen isotope ratios indicating a shallow water habitat. On the other hand, Pearson and others (2001) recorded a deep, thermocline signal. [Pearson et al. 2006] Aze et al. 2011 ecogroup 2 - Open ocean mixed-layer tropical/subtropical, without symbionts. Based on _13C lighter than species with symbionts; also with relatively light _18O. Sources cited by Aze et al. 2011 (appendix S3): Poore & Matthews (1984) Phylogenetic relationsEvolved from Turborotaliafrontosa, according to Toumarkine and Bolli (1970). [Pearson et al. 2006]
Most likely ancestor:Turborotalia frontosa - at confidence level 4 (out of 5). Data source: Pearson et al. (2006), fig 15.1.
Biostratigraphic distribution
Geological Range: Notes: Middle Eocene, middle Zone E9 to upper Zone E11 (Toumarkine and Bolli, 1970). [Pearson et al. 2006] Last occurrence (top): in upper part of E11 zone (80% up, 40.7Ma, in Bartonian stage). Data source: Pearson et al. (2006), fig. 15.1 First occurrence (base): in mid part of E9 zone (50% up, 43.5Ma, in Lutetian stage). Data source: Pearson et al. (2006), fig. 15.1
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
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: Pearson et al. 2006 - Eocene Atlas, chap. 15, p. 456
References:
Pearson, P. N., Premec-Fucek, V. & Premoli Silva, I. (2006b). Taxonomy, biostratigraphy, and phylogeny of Eocene Turborotalia. 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 15): 433-460. gsO
Poag, C. W. & Commeau, J. A. (1995). Paleocene to middle Miocene planktic foraminifera of the southwestern Salisbury Embayment, Virginia and Maryland: Biostratigraphy, allostratigraphy, and sequence stratigraphy. Journal of Foraminiferal Research. 25: 134-155. gs
Poore, R. Z. & Bybell, L. M. (1988). Eocene to Miocene biostratigraphy of New Jersey Core ACGS #4: Implications for regional stratigraphy. U.S. Geological Survey Bulletin. 1829: 1-41. gs
Poore, R. Z. & Matthews, R. K. (1984). Oxygen isotope ranking of late Eocene and Oligocene planktonic foraminifers: implications for Oligocene sea-surface temperatures and global ice-volume. Marine Micropaleontology. 9: 111-134. gs
Toumarkine, M. & Bolli, H. M. (1970). Evolution de Globorotalia cerroazulensis (Cole) dans l'Eocene moyen et superieur de Possagno (Italie). Revue de Micropaléontologie. 13(3): 131-145. gs
Toumarkine, M. & Luterbacher, H. (1985). Paleocene and Eocene planktic foraminifera. In, Bolli, H. M., Saunders, J. B. & Perch-Neilsen, K. (eds) Plankton Stratigraphy. Cambridge Univ. Press, Cambridge 87-154. gs
Toumarkine, M. (1975). Middle and Late Eocene planktonic foraminifera from the northwestern Pacific Ocean: Leg 32 of the Deep Sea Drilling Project. Initial Reports of the Deep Sea Drilling Project. 32: 735-751. gs
Turborotalia possagnoensis compiled by the pforams@mikrotax project teamviewed: 6-2-2025