Globorotalia inflata d'Orbigny 1839 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 . |
Notice: This catalogue page may contain unedited data.
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Species Globorotalia inflata d'Orbigny 1839 |
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Alternative name: |
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Discussion / Comments: |
Iaccarino (1985):
The morphologic features of the species are fully described and discussed in Banner & Blow (1967) and in Stainforth et al. (1975).
Controversial opinions concern the evolution of G. inflata. According to Colalongo & Sartoni (1967) it evolved from G. bononiensis, which in turn derived from G.puncticulata. Also Gradstein (1974) and Zachariasse (1975) recorded a transition from G. bononiensis to G. inflata, the main morphologic change concerning the height of the aperture, the shape of the chambers and their numbers. This transition according to the latter authors could reflect a more widespread evolutionary change. Contrary to Colalongo & Sartoni, however,
they did not record an evolutionary trend from G. puncticulata to G. bononiensis or from G. puncticulata to G. inflata as suggested by Kennett (1973) and by Cita (1973). In fact, Kennett believes that G. inflata evolved directly from G. puncticulata. If this were so, an overlap of the two taxa would he expected, which however does not occur in the Mediterranean Basin, where G. puncticulata disappears before the first occurrence of G. inflata.
In order to clear up the controversy, the most significant morphologic features of the three species and the major differences must be compared. G. puncticulata and G. inflata by definition possess curved intercameral sutures differing from those of G. bononiensis, which are radial. On the other hand the illustration of the neotype of G. inflata by Banner & Blow does not distinctly show this feature. In G. inflata 'the early chambers, in dorsal view, are reniform in outline but become increasingly larger than broad during ontogeny' (Banner & Blow, 1967); in G. puncliculata they are 'lunate in shape being much larger circumferentially than broad radially, a feature which becomes accentuated during ontogeny' (Banner & Blow, 1960). In G. bononiensis the shape of the chambers is ovate.
Following the concept that in an evolutionary trend a morphologic character acquired by a species cannot be reversed, it results that:
(1) If G. inflata has derived from G. bononiensis the latter
cannot evolve from G. puncticulata because the intercameral sutures are curved in puncticulata, straight in bononiensis and curved again in inflata.
(2) If G. inflata has derived directly from G. puncticulata, G.
bononiensis has to be regarded as belonging to a different lineage or to another branch of G. puncticulata.
The first appearance of G. inflata in the Mediterranean area is considered an important biostratigraphic event marking the base of the last zone of the Pliocene. It is recorded up to the Holocene. G. inflata is very common in the western Mediterranean and is scarce or absent in the eastern Mediterranean (Bizon & Müller, 1978). On the basis of its scarcity in this part of the Mediterranean, Bizon & Müller infer that G. inflata is not a useful index fossil for the uppermost Pliocene
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Systematics: |
1 Superregnum Eukaryota
Regnum Protoctista
Phylum Ciliophora
Subphylum Postciliodesmatophora
Ordo Globigerinida
Superfamilia Globorotaliaceae
Superfamilia Nonionacea
Familia Globorotaliidae
Genus Globorotalia
Species Globorotalia inflata
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Synonym list: |
Iaccarino (1985):
Vincent & Toumarkine (1990):
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Was used in synonym list of: |
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Stratigraphy - absolute ages: |
FAD: 2.09 ± 0 [Ma], Berggren et al. (1995) Mediterranean
FAD: 2.09 ± 0 [Ma], Berggren et al. (1995) North Atlantic
RAP: 1.99 ± 0 [Ma], Berggren et al. (1995) Mediterranean
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References: |
d'Orbigny,A.D. (1839): Foraminfères des Iles Canaries. In: Histoire naturelle des Iles Canaries Vol. 2(2) Eds: Barker Webb, P.Berthelot, S.
Banner,F.T. and Blow,W.H. (1967): The origin, evolution and taxonomy of the foraminiferal genus Pulleniatina Cushman, 1927 . Micropaleontology Vol. 13(2) p. 133-162
Iaccarino,S. (1985): Mediterranean Miocene and Pliocene planktic foraminifera. In: Plankton stratigraphy Eds: Bolli, H.M.Saunders, J.B.Perch-Nielsen, K. p. 283-314
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
Berggren,W.A.; Hilgen,F.J.; Langereis,C.G.; Kent,D.V.; Obradovich,J.D.; Raffi,I.; Raymo,M.E. and Shackleton,N.J. (1995): Late Neogene chronology: New perspectives in high-resolution stratigraphy . Geological Society of America Bulletin Vol. 107(11)
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