Globoquadrina venezuelana Hedberg 1937 from: Vincent, E.Toumarkine, M. (1990): Neogene planktonic foraminifers from the Western Tropical Indian Ocean, Leg 115. In: Proceedings of the Ocean Drilling Program, Scientific Results Vol. 115 Eds: Duncan, R.A..Backman, J.Peterson, L.C. p. 795-836 . |
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To find validated information on this taxon please visit the following project pages: |
Species Globoquadrina venezuelana Hedberg 1937 |
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Diagnosis / Definition: |
Kennett & Srinivasan (1983):
Test large, equatorial periphery slightly lobulate; chambers spherical to ovate, inflated, four in the final whorl, increasing in size rapidly; final chamber usually irregular;
sutures on spiral side slightly curved, depressed;on umbilical side radial, depressed; surface densely perforate, distinctly cancellate; umbilicus fairly wide, roughly rectangular; aperture interiomarginal, umbilical with umbilical teeth. |
Discussion / Comments: |
Chaisson & Pearson (1997):
In all samples between 154-925B-30H-5, 65-67 cm, and 25H-
5, 65-67 cm (except 29H-5, 65-67 cm) Gq. venezuelana specimens have an uncharacteristically loose trochospire with a very open umbilicus and inflated chambers, causing them to closely resemble Gq. pseudofoliata, a Pliocene
taxon that may have descended from Gq. venezuelana (Thompson and Sciarrillo,1978). Gq. venezuelana specimens often have a flap-like, kummerform chamber covering the umbilicus. Gq. venezuelana specimens in Sample 154-
925B-29H-5, 65-67 cm, have a more normal morphology. Chambers are compressed and the overall appearance is similar to that of Gq. dehiscens.
Chaisson & Leckie (1993):
Remarks: The shape of the chambers in the final whorl of this species can
vary markedly from specimen to specimen. There are, however, consistently
four in the final whorl, with the last often irregular in shape and bent toward
the umbilicus. Fifth chambers, when present, are very small and bulla-like.
Similar species: Parker (1967, p. 166) describes a gradual development of
Globoquadrina conglomerata from G. venezuelana from the upper Pliocene
into the basal Pleistocene. The former species has a more open umbilicus and
more inflated chambers. |
Systematics: |
1 Superregnum Eukaryota
Regnum Protoctista
Phylum Ciliophora
Subphylum Postciliodesmatophora
Ordo Globigerinida
Superfamilia Globorotaliaceae
Superfamilia Nonionacea
Familia Catapsydracidae
Genus Globoquadrina
Species Globoquadrina venezuelana
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Synonym list: |
Kennett & Srinivasan (1983):
Chaisson & d'Hondt (2000):
Chaisson & Pearson (1997):
Srinivasan (1975):
Vincent & Toumarkine (1990):
Chaisson & Leckie (1993):
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Stratigraphy - absolute ages: |
LAD: 3 ± 0.05 [Ma], Chaisson & d'Hondt (2000) ODP Leg 165 Site 999
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References: |
Hedberg,H.D. (1937): Foraminifers of the middle Tertiary Carapita Formation of northeastern Venezuela. . Journal of Paleontology Vol. 11(8) p. 661-697
Srinivasan,M.S. (1975): Middle Miocene Planktonic Foraminifera from the Hut Bay Formation, Little Andaman Island, Bay of Bengal . Micropaleontology Vol. 21(2) p. 133-150
Kennett,J. and Srinivasan,M.S. (1983): Neogene Planktonic Foraminifera - A Phylogenetic Atlas.
Vincent,E. and Toumarkine,M. (1990): Neogene planktonic foraminifers from the Western Tropical Indian Ocean, Leg 115. In: Proceedings of the Ocean Drilling Program, Scientific Results Vol. 115 Eds: Duncan, R.A..Backman, J.Peterson, L.C. p. 795-836
Chaisson,W.P. and Leckie,R.M. (1993): High-Resolution Planktonic Foraminifer Biostratigraphy of Site 806, Ontong Java Plateau (Western Equatorial Pacific). In: Proceedings of the Ocean Drilling Program, Scientific Results Vol. 130 Eds: Berger, W.H.Kroenke, L.W..Mayer, L.A..et al. p. 137-178
Chaisson,W.P. and Pearson,P.N. (1997): Planktonic foraminifer biostratigraphy at Site 925: middle Miocene–Pleistocene. In: Proceedings of the Ocean Drilling Program, Scientific Results Vol. 154 Eds: Shackleton, N.J.Curry, W.B.Richter, C.Bralower, T.J.
Chaisson,W.P. and d'Hondt,S.L. (2000): Neogene planktonic foraminifer biostratigraphy at Site 999, Western Caribbean Sea. In: Proceedings of the Ocean Drilling Program, Scientific Results Vol. 165 Eds: Leckie, R.M.Sigurdsson, H.Acton, G.D.Draper, G. p. 19-56
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