Cassigerinella chipolensis


Classification: pf_cenozoic -> microperforate -> Cassigerinellidae -> Cassigerinella -> Cassigerinella chipolensis
Sister taxa: C. chipolensis, C. eocaenica,

Taxonomy

Citation: Cassigerinella chipolensis (Cushman & Ponton 1932)
Rank: Species
Basionym: Cassidulina chipolensis
Synonyms:
Taxonomic discussion: Pokorny (1955) erected C. boudecensis to distinguish forms with a papillose surface texture from the smooth tests of C. chipolensis, and he designated C. boudecensis as the type species of Cassigerinella. Later, Pokorny (in Eames and others
1962) considered boudecensis to be a junior synonym of chipolensis. Subsequent workers adopted this view until Li (1986) regarded the presence of pore cones in boudecensis as a key criterion for distinguishing that species from the smooth-walled chipolensis. In a more recent paper, however, Li and McGowran (1996) treated boudecensis as a morphotype of chipolensis rather than as a distinct species. This is a prudent approach that is adopted in the present study, as observation of pore cones using only a light microscope may be difficult and the stratigraphic ranges of forms with pore cones and those without have never been shown to differ. [Huber et al. 2006]

Catalog entries: Cassidulina chipolensis;
Cassigerinella boudecensis;

Type images:

Short diagnosis: Differs from C. eocaenica by having a broader and more globular test and a planispirally or pseudoplanispirally enrolled coiling mode rather than a biserially enrolled coiling mode.

NB The short diagnoses are used in the tables of daughter-taxa to act as quick summaries of the differences between e.g. species of one genus. They have initially been copied from the diagnostic characters/distinguishing features sections of the Eocene and Paleocene Atlases, they will be edited as the site is developed.

Description


Diagnostic characters: Differs from C. eocaenica by having a broader and more globular test and a planispirally or pseudoplanispirally enrolled coiling mode rather than a biserially enrolled coiling mode. [Huber et al. 2006]

Wall type: Normal perforate, surface smooth or papillose with randomly distributed pore cones. [Huber et al. 2006]

Test morphology: Test small, outline subrectangular to elliptical, periphery strongly lobate; coiling mode biserially-planispirally enrolled or pseudoplanispiral; chambers subglobular, inflated, 7-8 visible externally, increasing rapidly in size; sutures depressed, distinct; aperture a broad or sometimes virguline-shaped, highly arched opening at the base of the final chamber, bordered by an asymmetrically thickened narrow lip. [Huber et al. 2006]

Size: Holotype length 0.15 mm, width 0.12 mm; lengths typically varying from 0.10 to 0.22 mm. [Huber et al. 2006]

Character matrix

test outline:Ellipticalcoiling axis:N/Achamber arrangement:Pseudoplanispiralumbilicus:Narrow
edge view:Inequally biconvexumbilical or test sutures:Strongly depressedspiral sutures:Strongly depressedshell porosity:Finely Perforate: 1-2.5
wall texture:Smoothaperture:Extraumbilicalaperture border:Thick lipaccessory apertures:None
periphery:N/Aumb chamber shape:Inflatedsp chbr shape:Inflatedperiph margin shape:Broadly rounded
umb depth:Deepdiameter mm:0.15width mm:0.12breadth mm:
final-whorl chambers:5.0-6.0

Biogeography and Palaeobiology


Geographic distribution: Low to middle latitudes; in the Southern Hemisphere chipolensis has not been reported southwards of ODP Site 703 in the southeast South Atlantic Ocean. [Huber et al. 2006]

Isotope paleobiology: In their study of stable isotope depth rankings of Oligocene planktonic foraminifera from the equatorial Atlantic, Boersma and Shackleton (1978) state that Cassigerinella consistently plots with Chiloguembelina, and Pseudohastigerina and is considered as an upper mixed layer dwelling species. [Huber et al. 2006]

Phylogenetic relations: Probably derived from C. eocaenica during the latest Eocene (Li, 1986) following an increased inflation of the test and a switch from a biserially enrolled coiling mode to a planispirally or pseudoplanispirally enrolled coiling mode. [Huber et al. 2006]

Biostratigraphic distribution

Geological Range:
Notes: Uppermost Eocene Zone E16 to middle Miocene Zone Mi13a. Because of its small size, rare abundance, and sporadic distribution, the lowest occurrence of C. chipolensis has been recorded at different levels at different sites. In the Mediterranean regions, the LO of chipolensis was recorded both above and below the first occurrence of Orbulina (Martinotti, 1989), whereas this datum was recorded in Zone P21 (=Zone O4-O5) at Cape May (Liu and others, 1997), and Zone P18 (=Zone O1) at Ceara Rise ODP Leg 154 (Pearson and Chaisson, 1997) and in southern Australia (Li and McGowran, 1996). Nocchi and others (1991) reported chipolensis within a short interval of Zone P21a (=Zone O4) at ODP Holes 703A and 704B in the southeast South Atlantic. In New Zealand chiploensis occurs sporadically in lower Oligocene through middle Miocene sediments (Jenkins, 1971). The only uppermost Eocene occurrence of chipolensis is here reported from the Leg 150X Atlantic City borehole (Pl.16.4, Figs. 26, 27), which was assigned to Zone P15 (=E14) by Liu and others (1997). [Huber et al. 2006]
Last occurrence (top): within M13 zone (6.14-9.83Ma, top in Messinian stage). Data source: Eocene Atlas
First occurrence (base): within E16 zone (33.90-34.68Ma, base in Priabonian stage). Data source: Eocene Atlas

Plot of occurrence data:

Primary source for this page: Huber et al. 2006 - Atlas of Eocene Planktonic Foraminifera, chapter 16, p. 484

References:

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, 1413 pp.

Boersma, A. & Shackleton, N.J., (1978). Oxygen and carbon isotope record through the Oligocene, Site 366 (equatorial Atlantic). Initial Reports of the Deep Sea Drilling Project, 41: 957-962.

Bolli, H.M., (1957). Planktonic foraminifera from the Oligocene-Miocene Cipero and Lengua formations of Trinidad, B.W.I. In: Loeblich, A.R., Jr. et al. (Editors), Studies in Foraminifera: U.S. National Museum Bulletin 215. U.S. Government Printing Office, Washington, DC, pp. 97-123.

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

Huber, B.T.; Olsson, R.K. & Pearson, P.N., (2006). Taxonomy, biostratigraphy, and phylogeny of Eocene microperforate planktonic foraminifera (Jenkinsina, Cassigerinelloita, Chiloguembelina, Streptochilus, Zeauvigerina, Tenuitella, and Cassigerinella) and Problematica (Dipsidripella). In: Pearson, P.N. et al. (Editors), Atlas of Eocene Planktonic Foraminifera, Cushman Foundation Special Publication 41. Cushman Foundation Special Publication. Allen Press, Lawrence, Kansas, pp. 461-508.

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

Leckie, R.M.; Farnham, C. & Schmidt, M.G., (1993). Oligocene planktonic foraminifer biostratigraphy of Hole 803D (Ontong Java Plateau) and Hole 628A (Little Bahama Bank), and comparison with the southern high latitudes. In: Berger, W.H., Kroenke, L.W. and al., e. (Editors), Proceedings of the Ocean Drilling Program, Scientific Results. Ocean Drilling Program, College Station, Texas, pp. 113-136.

Li, Q. & McGowran, B., (1996). The planktonic foraminifer Cassigerinella winniana (Howe) from southern Australia: Comments on its lineage recognition. Revista Española de Micropaleontología, 28: 97-103.

Li 1986 [sorry, not in our bibliography yet]

Liu, C.; Browning, J.V.; Miller, K.G. & Olsson, R.K., (1997). Upper Cretaceous to Miocene planktonic foraminiferal biostratigraphy: Results of Leg 150X, the New Jersey Coastal Plain Drilling Project. In: Miller, K.G. and Snyder, S.W. (Editors), Proceedings of the Ocean Drilling Program, Scientific Results. Ocean Drilling Program, College Station, Texas, pp. 111-127.

Loeblich, A.R., Jr. & Tappan, H., (1957). Planktonic foraminifera of Paleocene and early Eocene Age from the Gulf and Atlantic coastal plains. In: Loeblich, A.R., Jr. et al. (Editors), Studies in Foraminifera, U.S. National Museum Bulletin 215. U.S. Government Printing Office, Washington, D.C., pp. 173-198.

Pearson, P.N. & Chaisson, W.P. (Editors), (1997). Late Paleocene to middle Miocene planktonic foraminifer biostratigraphy, Ceara Rise. Proceedings of the Ocean Drilling Program, Scientific Results, 154. Ocean Drilling Program, College Station, TX, 33-68 pp.

Pokorny, V., (1955). Cassigerinella boudecensis, n. gen., n. s.p. (Foraminifera, Protozoa) from the Oligocene of the Zdanice Flych). Vestnik UUG, 30: 136-140.


Cassigerinella chipolensis compiled by the pforams@mikrotax project team viewed: 23-5-2017

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