Catapsydrax africanus Blow & Banner 1962 from: Pearson, P.N.Olsson, R.K.Hemleben, C.Huber, B.T.Berggren, W.A. (2006): Atlas of Eocene Planktonic Foraminifera. p. 1-513 . |
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Species Catapsydrax africanus Blow & Banner 1962 |
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Diagnosis / Definition: |
Pearson et al. (2006):
DESCRIPTION. Type of wall: Cancellate, apparently spinose,
ruber/sacculifer-type wall texture. 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.
Size: Maximum diameter of holotype 0.23 mm,
thickness 0.22 mm. |
Discussion / Comments: |
Pearson et al. (2006):
DISTINGUISHING FEATURES. 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.
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. 3 1.2).
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/sacculifertype
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 (PI. 5.1, Figs. 4-7).
PHYLOGENETIC RELATIONSHIPS.- 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.
GEOGRAPHIC DISTRIBUTION.- Known from
tropical to mid latitude sites.
STABLE ISOTOPE PALEOBIOLOGY. No data
available. |
Systematics: |
22 Genus Catapsydrax
Species Catapsydrax africanus
35 Ordo Foraminiferida
Superfamilia Globigerinaceae
Familia Globigerinidae
Genus Catapsydrax
Species Catapsydrax africanus
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Synonym list: |
Spezzaferri & Silva (1990):
Pearson et al. (2006):
1962 Globigerinita africana Blow & Banner. - Blow & Banner : p.105 pl. 15; fig. A-C (holotype)[Globigerapsis siemi-involuta Zone,
Sample FCRM 1645, Lindi, Tanzania.]
1983 Globigerinita africana Blow & Banner. - Abdel-Kireem : p.88 pl. 2; fig. 14-15 [middle Eocene
Truncorotaloides rohri Zone, Mokattam Fm., Egypt]
? 2001 Catapsydrax africana Blow & Banner. - Warraich & Ogasawara : p.43 fig. 12: 1-3 [Zone E10/11, Kirthar
Fm., Sulaiman Range, Pakistan].
2006 Catapsydrax africanus Blow & Banner. - Pearson et al. : p.73 pl. 5.1; fig. 1-14 (pl. 5.1; fig. 1-3; new SEMs of holotype of Globigerinita africana Blow and Banner)
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Specimen: |
Natural History Museum, London, Inventory number: P. 44553
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References: |
Blow,W.H. and Banner,F.T. (1962): The Mid-Tertiary (Upper Eocene to Aquitanian) Globigerinaceae. In: Fundamentals of Mid‑Tertiary Stratigraphical Correlation Eds: Eames, F.E.Banner, F.T.Blow, W.H.Clarke, W.J. p. 61‑151
Blow,W.H. (1979): The Cainozoic Globigerinida. 3 Vols p. 1413 pp
Abdel-Kireem,M.R.. (1983): Planktonic foraminifera of Mokattam Formation (Eocene) of Gebel Mokattam, Cairo, Egypt . Revue de Micropaleontologie Vol. 28 p. 77-96
Spezzaferri,S. and Silva,I.S.. (1990): Oligocene planktonic foraminiferal biostratigraphy and paleoclimatic interpretation from Hole 538A, DSDP Leg 77, Gulf of Mexico . Palaeogeography, Palaeoclimatology, Palaeoecology Vol. 83 p. 217-263
Warraich,M.Y.. and 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 Geoscience University of Tsukuba, section B Vol. 22 p. 1-59
Pearson,P.N.; Olsson,R.K.; Hemleben,C.; Huber,B.T. and Berggren,W.A. (2006): Atlas of Eocene Planktonic Foraminifera. p. 1-513
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