Acarinina esnaensis

Classification: pf_cenozoic -> Truncorotaloididae -> Acarinina -> Acarinina esnaensis
Sister taxa: << < A. africana, A. sibaiyaensis, A. esnehensis, A. mckannai, 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 esnaensis (LeRoy 1953)
Rank: Species
Basionym: Globigerina esnaensis
Taxonomic discussion: This taxon has had a colorful history. Originally described from the upper Paleocene (Zone P4/5) of Egypt by LeRoy (1953), it was virtually simultaneously described from the upper Paleocene of the North Caucasus by Subbotina (1953) under the name Acarinina intermedia, with LeRoy’s taxon having (subjective synonym) seniority by 10 months. Since that time it has been recorded under a variety of names, as was already recognized over 40 years ago by McGowran (1965; see synonymy above). The synonymy of Acarinina esnaensis and A. intermedia was verified by one of us (WAB) in the course of examination of type material of intermedia in the collections of N .N. Subbotina at VNIGRI (in 1962 and 1977) in Leningrad/ St. Petersburg and subsequent comparison of topotype material provided by Subbotina with the holotype of A. esnaensis in the Cushman collections of the USNM.
Acarinina esnaensis is generally characterized by a relatively flat spiral side and varies from having globular to subangular chambers in peripheral edge view (compare the illustrations in McGowran [1965] with illustrations of esnaensis and irrorata and tribulosa in Loeblich and Tappan [1957]). Forms with an odd/ anomalous apertural modification (a vertically disposed, narrow, slit-like aperture) are included here in this taxon; compare Loeblich and Tappan (1957, pl. 61: figs. 9a-c) with Berggren (1960a, pl. 5. figs. 3a-d) from Zone P7 of the Røsnaes Clay Fm., Røgle Klint, Denmark.
The holotype specimens of esnaensis and wilcoxensis are markedly similar. However, examination of large suites of individuals reveals that there are two separate and distinct taxa involved. Acarinina esnaensis is generally more elongate-oval in outline, and has a narrower umbilicus than A. wilcoxensis.
Blow (1979, p. 906) considered Acarinina intermedia to have evolved from A. acarinata (= nitida) and to have been ancestral to A. wilcoxensis and also to the A. pseudotopilensis -topilensis s.l. lineage. The transition to A. pseudotopilensis was said to involve a tangential lengthening of the later chambers at the expense of their radial width concomitant with these same chambers becoming disjunct and slightly laterally angulate. Blow (1979, p. 906) pointed to (paratypic) individuals referred to, and illustrated as, A. intermedia by Subbotina (1953, pl. 21, figs. 9a-c and pl. 22, figs. 2a-c) as representing intermediate forms between the two taxa. These views are supported by our own observations on comparative material. [Berggren et al. 2006]

Catalog entries: Globigerina esnaensis

Type images:

Distinguishing features: Test generally elongate-oval, with 4 chambers in the final whorl, narrow umbilicus; later chambers on spiral side tangentially longer than radially broad.

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.


Wall type: Muricate, non-spinose, normal perforate. [Berggren et al. 2006]

Morphology: Low-trochospiral, subquadrate test with somewhat lobulate peripheral outline; periphery rounded to subacute; 4-4½ subovate to subspherical chambers in final whorl, moderately inflated; intercameral sutures radial to slightly curved on umbilical side; umbilicus small, open; 12-15 chambers on spiral side, gradually increasing in size as added; sutures distinct, depressed, straight to slightly curved in direction of coiling; wall densely muricate, particularly along periphery; aperture a long, low interiomarginal, umbilical-extraumbilical arch extending nearly to the periphery with very thin lip. [Berggren et al. 2006]

Size: Maximum diameter of holotype 0.44 mm; thickness 0.26 mm. [Berggren et al. 2006]

Character matrix

test outline:Subquadratechamber arrangement:Trochospiraledge view:Equally biconvexaperture:Umbilical-extraumbilical
sp chamber shape:Inflatedcoiling axis:Lowperiphery:N/Aaperture border:Thin lip
umb chbr shape:Inflatedumbilicus:Narrowperiph margin shape:Broadly roundedaccessory apertures:None
spiral sutures:Moderately depressedumb depth:Deepwall texture:Coarsely muricateshell porosity:Finely Perforate: 1-2.5µm
umbilical or test sutures:Moderately depressedfinal-whorl chambers:4.0-4.5 N.B. These characters are used for advanced search. N/A - not applicable

Biogeography and Palaeobiology

Geographic distribution: Widespread in low latitudes, (sub)tropical latitudes as well as in high northern (Scandinavia) and southern/austral latitudes (e.g., Kerguelen Plateau, Maud Rise). [Berggren et al. 2006]
Aze et al. 2011 summary: Low to high latitudes; based on Berggren et al. (2006b)

Isotope paleobiology: No data available [Berggren et al. 2006]
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: This taxon is ancestral to Acarinina wilcoxensis and may have evolved from Acarinina nitida in the upper Paleocene (although it was not included in Olsson and others, 1999). [Berggren et al. 2006]

Most likely ancestor: Acarinina nitida - at confidence level 4 (out of 5). Data source: Berggren et al. (2006) fig9.2.
Likely descendants: Acarinina wilcoxensis;

Biostratigraphic distribution

Geological Range:
Notes: Zone P4 (upper part) to Zone E5. While this taxon has its lowest occurrence in upper Zone P4, we have found that it is particularly common and well developed within Zones P5-E2 and, in particular, within the interval of the Carbon Isotope Excursion (CIE) in the Bass River core drilled on the New Jersey Coastal Plain (basal Zone E1), where it occurs with early specimens of Acarinina wilcoxensis. The latter has its FAD just below the base of the CIE in Egypt. [Berggren et al. 2006]
Last occurrence (top): in upper part of E6 zone (70% up, 50.3Ma, in Ypresian stage). Data source: Eocene Atlas
First occurrence (base): within P5 zone (55.96-57.10Ma, base in Thanetian stage). Data source: Eocene Atlas

Plot of occurrence data:

Primary source for this page: Berggren et al. 2006 - Eocene Atlas, chap. 9, p. 286


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Berggren, W. A. (1977a). Atlas of Palaeogene Planktonic Foraminifera: some Species of the Genera Subbotina, Planorotalites, Morozovella, Acarinina and Truncorotaloides. In, Ramsay, A. T. S. (ed.) Oceanic Micropaleontology. Academic Press, London 205-300. gs

Berggren, W. A., Pearson, P. N., Huber, B. T. & Wade, B. S. (2006b). Taxonomy, biostratigraphy, and phylogeny of Eocene Acarinina. 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 9): 257-326. gs V O

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

Cushman, J. A. & Ponton, G. M. (1932a). An Eocene foraminiferal fauna of Wilcox age from Alabama. Contributions from the Cushman Laboratory for Foraminiferal Research. 8(3): 51-72. gs V O

El-Naggar, Z. R. (1966). Stratigraphy and planktonic foraminifera of the Upper Cretaceous-Lower Tertiary succession in the Esna-Idfu region, Nile Valley, Egypt, U. A. R. Bulletin of the British Museum (Natural History) Geology. supplement 2: 1-291. gs

Gartner, S. & Hay, W. W. (1962). Planktonic foraminifera from the type Ilerdian. Eclogae Geologicae Helvetiae. 55(2): 553-572. gs V O

Gohrbandt, K. (1963). Zur Gliederung des Palaeogen im Helvetikum nordlich Salzburg nach planktonischen Foraminiferen. Mitteilungen der Geologischen Gesellschaft in Wien. 56(1): 63-. 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 V O

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

LeRoy, L. W. (1953). Biostratigraphy of the Maqfi Section, Egypt. Geological Society of America, Memoir. 54: 1-73. 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

McGowran, B. J. (1965). Two Paleocene foraminiferal faunas from the Wangerrip Group, Pebble Point Coastal Section, Western Australia. Proceedings of the Royal Society of Victoria. 79: 9-74. gs

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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

Said, R. & Kenawy, A. (1956). Upper Cretaceous and lower Tertiary foraminifera from northern Sinai, Egypt. Micropaleontology. 2: 105-173. gs

Said, R. & Kerdany, M. T. (1961). The geology and micropaleontology of the Farafra Oasis, Egypt. Micropaleontology. 7: 317-336. gs

Said, R. & Sabry, H. (1964). Planktonic foraminifera from the type locality of the Esna Shale in Egypt. Micropaleontology. 10(3): 375-395. 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

Stott, L. D. & Kennett, J. P. (1991). Antarctic Paleogene Planktonic Foraminifer Biostratigraphy: ODP Leg 113, Sites 689 and 690. Proceedings of the Ocean Drilling Program, Scientific Results. 113: 549-569. gs


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

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