Catapsydrax africanus


Classification: pf_cenozoic -> Globigerinidae -> Catapsydrax -> Catapsydrax africanus
Sister taxa: C. indianus, 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:

Distinguishing features: Like C. howei but smaller and with smaller, less inflated bulla with 3-4 smaller, semi-circular infralaminal apertures.

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.

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:Umbilical
sp chamber shape:Inflatedcoiling axis:Highperiphery:N/Aaperture border:Bulla
umb chbr shape:Inflatedumbilicus:Narrowperiph margin shape:Broadly roundedaccessory apertures:Infralaminal
spiral sutures:Strongly depressedumb depth:Deepwall texture:Cancellateshell porosity:Macroperforate: >2.5µm
umbilical or test sutures:Strongly depressedfinal-whorl chambers:3.0-4.0 N.B. These characters are used for advanced search. N/A - not applicable

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 - Eocene Atlas, chap. 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. gs

Blow, W. H. & Banner, F. T. (1962). The mid-Tertiary (Upper Eocene to Aquitanian) Globigerinaceae. In, Eames, F. E. , Banner, F. T. , Blow, W. H. & Clarke, W. J. (eds) Fundamentals of mid-Tertiary Stratigraphical Correlation. Cambridge University Press, Cambridge 61-151. 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. (1957b). Planktonic foraminifera from the Oligocene-Miocene Cipero and Lengua formations of Trinidad, B.W.I. 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: 97-123. gs

Olsson, R. K., Pearson, P. N. & Huber, B. T. (2006c). Taxonomy, biostratigraphy, and phylogeny of Eocene Catapsydrax, Globorotaloides, Guembelitrioides, Paragloborotalia, Parasubbotina, and Pseudoglobigerinella n. gen. 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 5): 67-110. 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


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Catapsydrax africanus compiled by the pforams@mikrotax project team viewed: 18-11-2019

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