Acarinina sibaiyaensis El Naggar 1966 from: Pearson, P.N.Olsson, R.K.Hemleben, C.Huber, B.T.Berggren, W.A. (2006): Atlas of Eocene Planktonic Foraminifera. p. 1-513 | . |
Notice: This catalogue page may contain unedited data.
|
Species Acarinina sibaiyaensis El Naggar 1966 |
|
|
|
| Diagnosis / Definition: |
Pearson et al. (2006):
DESCRIPTION.
Type of wall: Muricate, nonspinose, normal
perforate.
Test morphology: Planoconvex; generally
umbilico-convex, although some specimens approach
being planispiral; peripheral margin round to subround;
chambers inflated, subtriangular to round on both
umbilical and spiral sides; approximately 12- 14
chambers arranged in 3 whorls; gradual increase in
chamber size throughout; sutures depressed and radial;
primary aperture circular, arch-like opening with lip to
well-developed flange, umbilical-extraumbilical position Size: Maximum diameter of holotype 0.29 mm,
minimum diameter 0.19 mm, thickness 0.17 mm; our
observations suggest that this form is typically <0.35
mm in maximum diameter. |
| Discussion / Comments: |
Pearson et al. (2006):
DISTINGUISHING FEATURES.-
Diagnostic
characteristics are the relatively large (5-9) number of
chambers in final whorl, and the test coiled in a very
low trochospiral (approaching planispiral) mode.
DISCUSSION.-
This form, together with A. africana
and Morozovella allisonensis, constitute an assemblage
of small, morphologically distinct taxa that are
characteristic of the temporally short (-200 kyrs)
Paleocene Eocene Thermal Maximum.
PHYLOGENETIC RELATIONSHIPS.-
Kelly and
others (1996) suggested that this taxon evolved from
Acarinina soldadoensis, but it shows much greater
similarity with A. esnehensis which we suggest was the
ancestor. Further flattening of the test produced the
africana morphology (Kelly and others, 1998).
STRATIGRAPHIC RANGE.-
Zone El, restricted to
carbon isotope excursion of the PETM.
GEOGRAPHIC DISTRIBUTION.-
Widely distributed
throughout the (sub)tropics and temperate regions;
common in the central equatorial Pacific (ODP Site 865),
found in New Jersey Coastal Plain (Bass River), North
Atlantic Ocean (ODP Site 1051), and also present in
Tethyan sections of Europe (Alamedilla, Spain) and
North Africa (Egypt).
STABLE ISOTOPE PALEOBIOL0GY.-
Inferred
depth-habitat primarily shallow mixed-layer; carbon
isotope signature exhibits strong covariance with shell
size; overall stable isotopic signature is analogous to that
of modem, symbiotic species (Kelly and others, 1998). |
| Systematics: |
35
Ordo Foraminiferida
Superfamilia Globigerinaceae
Familia Truncorotaloididae
Genus Acarinina
Species Acarinina sibaiyaensis
|
| Synonym list: |
Pearson et al. (2006):
1966 Globorotalia sibaiyaensis El Naggar. - El Naggar : p.235 pl. 23; fig.6a-c [G. aequa/G. esnaensis Subzone, G. velascoensis
Zone, Gebel Owaina section, Egypt]
1996 Acarinina sibaiyaensis El Naggar. - Kelly et al. : p.424 fig. 2.1a-b [upper Zone P5, from within carbon
isotope excursion of the Paleocene-Eocene Thermal
Maximum, ODP Hole 865C, Allison Guyot, equatorial
Pacific Ocean]
1998 Acarinina sibaiyaensis El Naggar. - Kelly et al. : p.159 fig. 5c, 9d-e [upper Zone PS, from within carbon isotope excursion
of Palcocene-Eocene Thermal Maximum, ODP Hole
865C, Allison Guyot, equatorial Pacific Occan]
1999 Acarinina sibaiyaensis El Naggar. - PARDO et al. : p.44 pl. 2; fig. 19-20 [Zone P5b,
Kaurtakapy, Kazakhstan]
|
| Specimen: |
Natural History Museum, London, Inventory number: P. 45628
Natural History Museum, London, Inventory number: P. 45629
Smithsonian Museum of Natural History, Washington, D.C., Inventory number: USNM 494822
|
| References: |
El Naggar,Z.R.M. (1966):
Stratigraphy And Planktonic Foraminifera of the Upper Cretaceous - Lower Tertiary Succession in the Esna-Idfu Region. Nile Valley, Egypt . Egypt. Bull. Geol.Supp 2 p. 279 pp
Kelly,D.C.; Bralower,T.J.; Zachos,J.C.; Premoli Silva,I. and Thomas,E. (1996):
Rapid diversification of planktonic foraminifera in the tropical Pacific (ODP Site 865) during the late Paleocene thermal maximum . Geology Vol. 24 p. 423-426
Kelly,.; Bralower,. and Zachos,. (1998):
On the demise of the Early Paleogene Movozovella velascoensis lineage: terminal progenesis in the planktonic foraminifera . Palaios Vol. 16 p. 507-523
PARDO,A..; Keller,G. and Oberhansli,H.. (1999):
Paleoecologic and paleoceanographic evolution of the Tethyan realm during the Paleocene-Eocene transition . Journal of Foraminiferal Research Vol. 29 p. 37-57
Pearson,P.N.; Olsson,R.K.; Hemleben,C.; Huber,B.T. and Berggren,W.A. (2006):
Atlas of Eocene Planktonic Foraminifera. p. 1-513
|
This work is licensed under a Creative Commons Attribution 2.5 License.
|
|
Taxon Concept provided by