Catapsydrax africanus


Classification: pf_cenozoic -> spinose -> Globigerinidae -> Catapsydrax -> Catapsydrax africanus
Sister taxa: C. dissimilis, C. globiformis, C. africanus, C. howei, C. unicavus, C. sp.,

Taxonomy

Citation: Catapsydrax africanus (Blow and Banner 1962)
Rank: Species
Basionym: Globigerinita africana africanus
Synonyms:
Taxonomic discussion: Blow and Banner (1962) originally placed C. africanus in Globigerinita but this genus is a microperforate taxon, hence it is here placed in Catapsydrax. The species name is changed to agree in gender with the genus Catapsydrax (ICZN, Art. 31.2). Catapsydrax africanus, has a low, slightly inflated bulla covering the umbilicus with a single low arched aperture. The infralaminal aperture is bordered by a continuous narrow lip that becomes thickened with gametogenetic calcification. The wall texture of the ruber/sacculifer-type also becomes thickened by gametogenetic calcification. The wall texture of C. africanus is the same as in C. unicavus, and the infralaminal apertures are bordered by a continuous, narrow, thickened lip. In C. africanus the bulla is more inflated and the infralaminal apertures are larger. Blow (1979) regarded africanus as a subspecies of Catapsydrax echinatus Bolli, but that species is regarded as an aberrant acarininid in this work (see Berggren and others, Chapter 9, this volume). Catapsydrax africanus is a small form and has apparently been overlooked by many previous workers. We illustrate the holotype in SEM for the first time (Pl.5.1, Figs. 1-3) as well as newly collected specimens from the type locality (Pl.5.1, Figs. 4-7). [Olsson et al. 2006]

Catalog entries: Globigerinita africana;

Type images:

Short diagnosis: Catapsydrax africanus is distinguished from C. globiformis by its less spherical test and by having a more inflated bulla that has larger, more open, infralaminal apertures. Catapsydrax howei is larger and has a larger, still more inflated bulla with large circular, infralaminal apertures.

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: Catapsydrax africanus is distinguished from C. globiformis by its less spherical test and by having a more inflated bulla that has larger, more open, infralaminal apertures. Catapsydrax howei is larger and has a larger, still more inflated bulla with large circular, infralaminal apertures.

Wall type: Cancellate, apparently spinose, ruber/sacculifer-type wall texture. [Olsson et al. 2006]

Test morphology: Low trochospiral, slightly lobate test with 3-4 chambers in the final whorl. Chambers inflated, globular, increasing moderately in size with a large inflated bulla covering the umbilicus; in spiral view 3-4 globular chambers increasing moderately in size, sutures straight, moderately depressed; in umbilical view dominated by a large inflated bulla with 3-4 semicircular, infralaminal apertures with a continuous, thickened imperforate rim opening onto each suture which is straight and moderately depressed; in edge view ovoid in shape with bulla showing one aperture opening onto the suture line. [Olsson et al. 2006]

Size: Holotype maximum diameter 0.23 mm, thickness 0.22 mm. [Olsson et al. 2006]

Character matrix

test outline:Subquadratechamber arrangement:Trochospiraledge view:Equally biconvexaperture:Multiple
umb chamber shape:Inflatedcoiling axis:Highperiphery:N/Aaperture border:Thin lip
sp chbr shape:Inflatedumbilicus:Narrowperiph margin shape:Broadly roundedaccessory apertures:Sutural
umbilical or test sutures:Strongly depressedumb depth:Deepwall texture:Cancellateshell porosity:Macroperforate: >2.5µm
spiral sutures:Strongly depresseddiameter mm:0.38width mm:breadth mm:
final-whorl chambers:3.0-4.0

Biogeography and Palaeobiology


Geographic distribution: Known from tropical to mid latitude sites. [Olsson et al. 2006]
Aze et al. 2011 summary: Low to middle latitudes; based on Olsson et al. (2006c)

Isotope paleobiology: No data available. [Olsson et al. 2006]
Aze et al. 2011 ecogroup 4 - Open ocean sub-thermocline. Based on very light δ13C and very heavy δ18O. Sources cited by Aze et al. 2011 (appendix S3): Keller (1985)

Phylogenetic relations: Catapsydrax africanus probably evolved from C. howei in the late middle Eocene by developing a less inflated bulla with smaller infralaminal apertures opening onto the sutures. [Olsson et al. 2006]

Most likely ancestor: Catapsydrax howei - at confidence level 4 (out of 5). Data source: Olsson et al. 2006 f5.1.

Biostratigraphic distribution

Geological Range:
Notes: Zone E13 (middle part; Abdel-Kireem, 1983) to Zone E15 (Blow and Banner, 1962). [Olsson et al. 2006]
Last occurrence (top): within E15 zone (34.68-35.89Ma, top in Priabonian stage). Data source: Olsson et al. 2006 f5.1
First occurrence (base): in mid part of E13 zone (50% up, 39Ma, in Bartonian stage). Data source: Olsson et al. 2006 f5.1

Plot of occurrence data:

Primary source for this page: Olsson et al. 2006 - Atlas of Eocene Planktonic Foraminifera, chapter 5, p. 70

References:

Abdel-Kireem, M.R., (1983). Planktonic foraminifera of Mokattam Formation (Eocene) of Gebel Mokattam, Cairo, Egypt. Revue de Micropaléontologie, 28: 77-96.

Blow, W.H. & Banner, F.T., (1962). The mid-Tertiary (Upper Eocene to Aquitanian) Globigerinaceae. In: Eames, F.E. et al. (Editors), Fundamentals of mid-Tertiary Stratigraphical Correlation. Cambridge University Press, Cambridge, pp. 61-151.

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.

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.

Olsson, R.K.; Pearson, P.N. & Huber, B.T., (2006). Taxonomy, biostratigraphy, and phylogeny of Eocene Catapsydrax, Globorotaloides, Guembelitrioides, Paragloborotalia, Parasubbotina, and Pseudoglobigerinella n. gen. 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. 67-110.

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.


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Catapsydrax africanus compiled by the pforams@mikrotax project team viewed: 19-11-2017

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