Acarinina strabocella

Classification: pf_cenozoic -> Truncorotaloididae -> Acarinina -> Acarinina strabocella
Sister taxa: << < A. subsphaerica ⟩⟨ A. bullbrooki, A. punctocarinata, A. boudreauxi, A. rohri, A. topilensis, A. praetopilensis, A. mcgowrani, A. quetra, A. pseudotopilensis, A. wilcoxensis, A. esnaensis, A. primitiva, A. coalingensis, A. nitida, A. strabocella, A. sp.


Citation: Acarinina strabocella (Loeblich and Tappan 1957)
Rank: Species
Basionym: Globorotalia strabocella
Taxonomic discussion: Shutskaya (1956; see also 1970a, 1970b) described Globorotalia angulata var. praepentacamerata from the lower Paleocene of the northern Caucasus and showed that it had a wide distribution in the southwestern part of the former Soviet Union. Luterbacher (1964:665) suggested that Globorotalia strabocella Loeblich and Tappan may be a junior synonym. We agree with this assessment particularly inasmuch as comparison of our material with the holotype of G. strabocella at the NMNH shows them to be morphologically similar. In view of the fact that there is no original (type) material remaining of Shutskaya's taxon (nor of any other taxa that she described, for that matter, with rare exception), we prefer to use the name strabocella for this taxon because of the fact that there is well-preserved type material at a readily accessible museum (the NMNH in Washington), which aids in stabilizing the nomenclature.
Shutskaya (1970b: 118, 120, fig. 13) showed that A. praepentacamerata is restricted to the A. praepentacamerata Zone and the lower subzone of the overlying A. tadjikistanensis djanensis Zone in the southwestern part of the former Soviet Union [= Zone P3 (middle part) to ? P4 [lower part)]. This is similar to our observations. The forms referred to A. wilcoxensis strabocella from Zones P6-P8b by Blow (1979:970, pis.
114, 129, 132, 251) are considered unrelated to strabocella; they differ in their more evolute coiling, flatter spiral coil, and strongly muricate ornament. They represent a younger, more advanced acarininid morphology than that seen in A. strabocella. In fact, we view A. strabocella as representing the stem form of the acarininid radiation that occurred at the P3-P4 zonal transition. [Olsson et al. 1999]

Catalog entries: Globorotalia strabocella, Globorotalia angulata praepentacamerata

Type images:

Distinguishing features: Test nearly circular, 5-6 chambers in final whorl, weakly lobulate outline; axial periphery broadly rounded to subangular, chambers on umbilical side moderately convex, early whorls on spiral side elevated above later whorl(s); umbilicus usually broad and open exposing earlier whorls; entire test weakly muricate, aperture an interiomarginal, umbilical-extraumbilical slit.

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.


Character matrix

test outline:Lobatechamber arrangement:Trochospiraledge view:Equally biconvexaperture:Umbilical-extraumbilical
sp chamber shape:Inflatedcoiling axis:Lowperiphery:N/Aaperture border:N/A
umb chbr shape:Inflatedumbilicus:Wideperiph margin shape:Broadly roundedaccessory apertures:None
spiral sutures:Strongly depressedumb depth:Shallowwall texture:Spinoseshell porosity:Finely Perforate: 1-2.5µm
umbilical or test sutures:Strongly depressedfinal-whorl chambers:5.0-6.0 N.B. These characters are used for advanced search. N/A - not applicable

Biogeography and Palaeobiology

Geographic distribution: Northern middle latitudes to the Southern Ocean (Figure 21). [Olsson et al. 1999]
Aze et al. 2011 summary: Northern middle latitudes to the Southern Ocean; based on Olsson et al. (1999)

Isotope paleobiology: No data available. [Olsson et al. 1999]
Aze et al. 2011 ecogroup 1 - Open ocean mixed-layer tropical/subtropical, with symbionts. Based on very heavy δ13C and relatively light δ18O. Sources cited by Aze et al. 2011 (appendix S3): this study

Phylogenetic relations: The origin of the first Acarinina species is somewhat obscure. The wall surface ofA. strabocella is smooth with simple and coalescent pustules (Plate 5: Figure 1) that become more heavily developed on the older part of the test. The origin of this species may be linked with the moderately pustulose Morozovella praeangulata in the lower part of Zone P3 and may have diverged from early forms of this species. Alternatively, A. strabocella may have evolved from Praemurica inconstans by developing a tighter coil and a lower rate of chamber enlargement. In any case, A. strabocella represents the stem form of the acarininid radiation. Reduction of the number of chambers in the final whorl and the increased development of muricae are seen in the derivation of A. nitida from A strabocella. [Olsson et al. 1999]

Most likely ancestor: Morozovella praeangulata - at confidence level 4 (out of 5). Data source: Olsson et al. 1999, fig5a.
Likely descendants: Acarinina nitida;

Biostratigraphic distribution

Geological Range:
Notes: Zone P3 (lower part) to Zone P4 (lower part). [Olsson et al. 1999]
Last occurrence (top): in lower part of P4 zone (30% up, 59.6Ma, in Thanetian stage). Data source: Olsson et al. 1999
First occurrence (base): within P3 zone (60.73-62.29Ma, base in Danian stage). Data source: Olsson et al. 1999

Plot of occurrence data:

Primary source for this page: Olsson et al. 1999 - Atlas of Paleocene Planktonic Foraminifera, p. 50


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

Huber, B. T. (1991d). Planktonic foraminifer biostratigraphy of Campanian-Maestrichtian sediments from ODP Leg 114, Sites 698 and 700, southern South Atlantic. Proceedings of the Ocean Drilling Program, Scientific Results. 114: 281-297. gs

Jenkins, D. G. (1971). New Zealand Cenozoic Planktonic Foraminifera. New Zealand Geological Survey, Paleontological Bulletin. 42: 1-278. gs

Loeblich, A. R. & Tappan, H. (1957b). Planktonic foraminifera of Paleocene and early Eocene Age from the Gulf and Atlantic coastal plains. 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: 173-198. gs V O

Luterbacher, H. P. (1964). Studies in some Globorotalia from the Paleocene and Lower Eocene of the Central Apennines. Eclogae Geologicae Helvetiae. 57: 631-730. gs V O

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

Shutskaya, E. K. (1956). Стратиграфия нижних горизонтов палеогена Центрального Предкавказья по фораминиферам - Stratigraphy of the lower horizons of the Paleogene of the central Precaucasus according to the foraminifera. Trudy Geologicheskiy Institut Akademiya Nauk SSSR, Geol. Ser. 71(164): 3-119. gs

Shutskaya, E. K. (1970a). Morphologic groups and descriptions of species of Globigerina and Acarinina in the lower Paleogene of the Crimea, the Caucasus Foreland, and western Central Asia. Trudy Vsesoyuznego Neftyanogo Nauchno-Issledovatel 'skogo Geologo-Razvedochnogo Instituta (VNIGRI). 69: 79-113. gs

Shutskaya, E. K. (1970b). Stratigrafiya, foraminifery i paleogeografiya nizhnego paleogena Kryma, predkavkaz'ya i zapadnoi chadsti srednei azii [Stratigraphy, Foraminifera and Paleogeography of the Lower Paleogene in the Crimea, Precaucasus and the Western Part of Central Asia]. Trudy Vsesoyuznego Neftyanogo Nauchno-Issledovatel 'skogo Geologo-Razvedochnogo Instituta (VNIGRI). 70(1): 256-. gs

Soldan, D. M., Petrizzo, M. R., Silva, I. P. & Cau, A. (2011). Phylogenetic relationships and evolutionary history of the Paleogene genus through parsimony analysis. Journal of Foraminiferal Research. 41: 260-284. gs

Stott, L. D. & Kennett, J. P. (1990). The Paleoceanographic and Paleoclimatic signature of the Cretaceous/Paleogene boundary in the Antarctic: Stable isotopic results from ODP Leg 113. Proceedings of the Ocean Drilling Program, Scientific Results. 113: 829-848. gs


Acarinina strabocella compiled by the pforams@mikrotax project team viewed: 21-4-2021

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