Praeorbulina transitoria Blow 1956 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.
To find validated information on this taxon please visit the following project pages: |
Species Praeorbulina transitoria Blow 1956 |
|
|
Diagnosis / Definition: |
Kennett & Srinivasan (1983):
Test low trochospiral, bilobate, chambers spherical, penultimate and ultimate chambers almost equal in size, embracing in early chambers; sutures on spiral side slightly
curved to radial, depressed; surface distinctly cancellate; apertures multiple, narrow, small slits confined to last sutures of the final and earlier chambers. |
Discussion / Comments: |
Kennett & Srinivasan (1983):
Pr. transitoria has an intermediate morphology linking its ancestor Gs. sicanus and its descendant 0. bilobata.
Bolli & Saunders (1985):
The presence of more than 2 apertures betwen the last chamber and earlier ones places this species in the genus Praeorbulina. It differs from G. bisphericus in being more symmetrically bilobate with the penultimate chamber occupying proportionally more of the test; morphologically intermediate forms can be found. |
Synonym list: |
Kennett & Srinivasan (1983):
Bolli & Saunders (1985):
Vincent & Toumarkine (1990):
|
References: |
Blow,W.H. (1956): Origin and evolution of the foraminiferal genus Orbulina d'Orbigny . Micropaleontology Vol. 2(1) p. 57-70
Kennett,J. and Srinivasan,M.S. (1983): Neogene Planktonic Foraminifera - A Phylogenetic Atlas.
Bolli,H.M. and Saunders,J.B. (1985): Oligocene to Holocene low latitude planktic foraminifers. In: Plankton Stratigraphy Eds: Bolli, H.M.Saunders, J.B. p. 155-262
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
|
This work is licensed under a Creative Commons Attribution 2.5 License.
|
|