pforams@mikrotax - Acarinina quetra

Citation: Acarinina quetra (Bolli 1957)

Synonyms:

Globorotalia quetra Bolli 1957a:79, pl. 19: figs. 1-3 (holotype), 4-6 (paratype) [Globorotalia formosa formosa Zone, upper Lizard Springs Fm., Trinidad].—Stainforth and others, 1975:221, text-figs. 80.1-6 [G. formosa Zone, Lizard Springs Fm., Trinidad]; 4-6 (from Bolli, 1957a, reillustrated).
Globorotalia (Acarinina) quetra Bolli.—Hillebrandt, 1962:144, pl. 14: figs. 2a-c [Zone G, Reichenhall Basin, south-west Germany].
Acarinina quetra (Bolli).—Fleisher, 1974, pl. 3: fig. 3 [Zone P8, DSDP Site 220, Arabian Sea].—Berggren, 1977: 251, chart no. 10 (reillustrations from literature).—Warraich and others, 2000:193, fig. 17.13-15 [Zone P7, Rakhi Nala section, Sulaiman Range, Pakistan].—Warraich and Ogasawara, 2001:29, figs. 7.4-6 [Zone P7, Rakhi Nala section, Sulaiman Range, Pakistan].
Globorotalia (Truncorotaloides) quetra (Bolli).—Blow, 1979:1034-1036 (note p. 1036 misprinted as 1136), pl. 122: figs. 4, 7-9 and pl. 200: figs. 5, 6 ; pl. 123: figs. 6-9, pl. 202: figs. 1-6 [lower Eocene Zone P7, DSDP Site 47, Shatsky Rise, north-west Pacific Ocean]; pl. 129: fig. 5 [lower Eocene Zone P8a, DSDP Site 47, Shatsky Rise, northwest Pacific Ocean]; pl. 132: figs. 7-9 and pl. 201: figs. 4-6 [lower Eocene Zone P7, DSDP Site 47, Shatsky Rise, northwest Pacific Ocean]; pl. 140: fig. 4 [lower Eocene Zone P8b, DSDP Site 20, South Atlantic Ocean].
Morozovella quetra (Bolli).—Snyder and Waters, 1985: 448, pl. 9: figs. 4-6 [lower Eocene Zone P6, DSDP Site 550, Porcupine Abyssal Plain, north-east Atlantic Ocean].

Taxonomic discussion: Acarinina quetra is a distinctive form that with its cuneate chambers and peripheral concentration of muricae, bears a superficial
resemblance (in some instances) to the stratigraphically younger (middle Eocene) A. topilensis. [Berggren et al. 2006]

Distinguishing features: Like A. pseudotopilensis but with angular test; chambers loosely disposed to each other at ~ 90°; and with a distinct, but discontinuous, peripheral muricocarina.

Description

Diagnostic characters: This taxon is distinguished by its angular test whose chambers are loosely disposed sequentially to each other at ~ 90o and with a distinct, but discontinuous, peripheral muricocarina. [Berggren et al. 2006]

Wall type: Moderately to strongly muricate with concentration of muricae along peripheral margin of last whorl, nonspinose, normal perforate. [Berggren et al. 2006]

Test morphology: Low trochospiral; test subquadrate, planoconvex; peripheral margin lobulate; chambers on umbilical side moderately inflated, flattened on spiral side; 4 broadly subtriangular chambers visible in umbilical view; anterior and posterior margins of last chamber flattened resulting in disjunct geometry with bordering chambers and conical apex of last chamber; sutures depressed/incised, curved to sinuous, radial; umbilicus relatively wide, deep; aperture an umbilical-extraumbilical, arch extending towards (but not to) the peripheral margin; 10-12 chambers in 2½ to 3 whorls on spiral side; chambers loosely disposed, meeting almost at right angles, increasing gradually in size; final chamber sometimes reduced in size; chambers lens-shaped, tangentially longer than radially broad in general, overlapping; sutures curved; discrete intercameral openings visible on some individuals (depending on preservation); planoconvex in edge view, final chamber distinctly anguloconical with high conical angle; periphery distinctly, but discontinuously, muricocarinate [Berggren et al. 2006]

Size: Maximum diameter of holotype 0.50 mm, thickness 0.38 mm. [Berggren et al. 2006]

Biogeography and Palaeobiology

Geographic distribution: Widely distributed in (sub)tropical regions (Caribbean, Atlantic, Indo-Pacific, Tethyan/Mediterranean regions, North Caucasus) [Berggren et al. 2006]
Aze et al. 2011 summary: Low 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: Descended from A. pseudotopilensis. [Berggren et al. 2006]

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

Biostratigraphic distribution

Geological Range:
Notes: Zone E3 (upper part) to Zone E6. [Berggren et al. 2006]
Last occurrence (top): within E6 zone (50.20-50.67Ma, top in Ypresian stage). Data source: Eocene Atlas
First occurrence (base): in upper part of E3 zone (80% up, 54.7Ma, in Ypresian stage). Data source: Eocene Atlas

Primary source for this page: Berggren et al. 2006 - Eocene Atlas, chap. 9, p. 310

References:

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 :: ::

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 :: ::

Fleisher, R. L. (1974a). Cenozoic planktonic foraminifera and biostratigraphy, Arabian Sea, Deep Sea Drilling Project, Leg 23A. Initial Reports of the Deep Sea Drilling Project. 23: 1001-1072. gs :: ::

Hillebrandt, A. , von (1962). Das Paleozän und seine Foraminiferenfauna im Becken von Reichenhall und Salzburg. Abhandlungen Bayerischen Akademie der Wissenschaften, Mathematisch-Naturwissenschaftliche Klasse, Neue Folge. 108: 1-182. gs :: ::

Snyder, S. W. & Waters, V. J. (1985). Cenozoic planktonic foraminiferal biostratigraphy of the Goban Spur Region, Deep Sea Drilling Project Leg 80. Initial Reports of the Deep Sea Drilling Project. 80: 439-472. gs :: ::

Stainforth, R. M., Lamb, J. L., Luterbacher, H., Beard, J. H. & Jeffords, R. M. (1975). Cenozoic planktonic foraminiferal zonation and characteristics of index forms. University of Kansas Paleontological Contributions. 62: 1-425. 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, Section B = Geological Sciences. 22: 1-59. gs :: ::

Warraich, M. Y., Ogasawara, K. & Nishi, H. (2000). Late Paleocene to early Eocene planktic foraminiferal blostratigraphy of the Dungan Formation, Sulaiman Range, central Pakistan. Paleontological Research. 4(4): 275-301, 218 figures, 273 aendices. gs :: ::

test outline:	Subquadrate	chamber arrangement:	Trochospiral	edge view:	Planoconvex	aperture:	Umbilical-extraumbilical
sp chamber shape:	Inflated	coiling axis:	Very low	periphery:	N/A	aperture border:	N/A
umb chbr shape:	Inflated	umbilicus:	Wide	periph margin shape:	Broadly rounded	accessory apertures:	Sutural
spiral sutures:	Moderately depressed	umb depth:	Deep	wall texture:	Coarsely muricate	shell porosity:	Finely Perforate: 1-2.5µm
umbilical or test sutures:	Moderately depressed	final-whorl chambers:	4.0-4.0	N.B. These characters are used for advanced search. N/A - not applicable

Acarinina quetra

Taxonomy

Description

Biogeography and Palaeobiology

Biostratigraphic distribution

References:

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