and Luterbacher, 1985). It is one of the earliest acarininids appearing together with A. subsphaerica at the base of Zone P4. Acarinina nitida represents an intermediate stage between the weakly muricate A. strabocella and the more strongly muricate upper Paleocene acarininids. Subbotina (1953) considered that acarinata ranged up to the base of her zone of conical globorotaliids (= P6a/b boundary of this work). Our observations agree more closely with Blow (1979), who indicated its LAD occurs in his Zone P5 or possibly lower P6.
The holotype of Acarinina intermedia Subbotina, 1953 (Plate 12: Figures 4-6), is a poorly preserved specimen with a missing ultimate chamber and an obscured umbilicus. The general morphology of this specimen shows four chambers in the ultimate whorl and heavily muricate umbilical shoulders suggesting a linkage to nitida. Acarinina nitida has also been previously identified under different names (see synonomy) by Weiss (1955), Bolli (1957a), and Loeblich and Tappan (1957a). [Olsson et al. 1999]
Catalog entries: Globigerina nitida, Acarinina acarinata, Acarinina intermedia, Globigerina stonei
Type images:Distinguishing features:
Parent taxon (Acarinina): Moderate to low trochospire; chambers ovoid, usually 4-6 in final whorl.
Wall muricate with pustules on umbilical shoulders;
This taxon: Test compact, small, trochospiral, with 4 (rarely 5) rounded, tightly packed, radially compressd and axially elongate chambers; early whorls raised above surface of last whorl; moderately muricate, particularly on umbilical side.
Character matrix
| test outline: | Circular | chamber arrangement: | Trochospiral | edge view: | Equally biconvex | aperture: | Umbilical-extraumbilical |
| sp chamber shape: | Inflated | coiling axis: | Low | periphery: | N/A | aperture border: | N/A |
| umb chbr shape: | Inflated | umbilicus: | Narrow | periph margin shape: | Broadly rounded | accessory apertures: | None |
| spiral sutures: | Moderately depressed | umb depth: | Deep | wall texture: | Moderately muricate | shell porosity: | Finely Perforate: 1-2.5µm |
| umbilical or test sutures: | Moderately depressed | final-whorl chambers: | 4-4 | N.B. These characters are used for advanced search. N/A - not applicable | |||
Most likely ancestor:
Acarinina strabocella - at confidence level 4 (out of 5). Data source: Olsson et al. 1999, fig5a.
Likely descendants: Acarinina coalingensis; Acarinina esnaensis; Acarinina subsphaerica;
plot with descendants
Geological Range:
Notes: Zone P4a to lower Zone P4c. [Olsson et al. 1999]
Last occurrence (top): in upper part of P4c subzone (60% up, 57.4Ma, in Thanetian stage). Data source: Olsson et al. 1999
First occurrence (base): within P4a subzone (60.52-60.73Ma, base in Selandian 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. 48
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. (1957d). The genera Globigerina and Globorotalia in the Paleocene-Lower Eocene Lizard Springs Formation 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: 61-82. gs Brönnimann, P. (1952d). Trinidad Paleocene and lower Eocene Globigerinidae. Bulletins of American Paleontology. 34(143): 1-34. 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 Martin, L. T. (1943). Eocene foraminifera from the type Lodo Formation, Fresno County, California. Stanford University Publications, Geological Sciences. 3(3): 1-35. gs Olsson, R. K., Hemleben, C., Berggren, W. A. & Huber, B. T. (1999). Atlas of Paleocene Planktonic Foraminifera. Smithsonian Institution Press, Washington, DC. (85): 1-252. 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 Subbotina, N. N. (1953). Foraminiferes fossiles d'URSS Globigerinidae, Globorotaliidae, Hantkeninidae. Bureau de Recherches Geologiques et Minieres. 2239: 1-144. gs Weiss, L. (1955a). Foraminifera from the Paleocene Pale Greda Formation of Peru. Journal of Paleontology. 29(1): 1-21. gsReferences:

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Acarinina nitida compiled by the pforams@mikrotax project team viewed: 11-2-2026
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