|- divided into two main lineage groups and within these ordered by FO (time control age-window is: 0-800Ma)|
|lineage group B - inflated chambers, perforate walls|
Test small. Final whorl with 4 low conical chambers and an acute axial periphery. Axial periphery imperforate, becoming thickened on the last chambers.
Test very low trochospiral. Chambers globular. Axial periphery rounded. Aperture arched, extending over axial periphery to spiral side, but not to the trace of the spiral suture.
5-6 inflated chambers in the final whorl, very low coiling axis.
Test small. Final whorl with 4-4½ (rarely 5) inflated ovoid chambers. Aperture a high umbilical-extraumbilical arch with thin continuous lip.
5 chambers in the final whorl, increasing moderately in size. The chambers are more inflated than in G. archeocompressa and globular to ovoid.
|lineage group A - compressed tests, imperforate margin|
Test small highly compressed, with well-developed, thickened, imperforate peripheral margin. Final whorl with 5-6 (rarely 7) chambers, equatorial periphery rounded becoming lobulate. Aperture high umbilical-extraumbilical arch with thin, continuous lip.
Test compressed, periphery pinched with a thickened imperforate band. 5-6 rapidly enlarging chambers in final whorl.
Test spiroconvex with distinct keel & sharply-angled axial periphery. Umbilicus narrow. 5 (rarely 6) chambers in final whorl.
Test compressed, smooth-walled, chambers moderately increasing in size. Periphery pinched with a thickened imperforate margin (faint keel). 5-5½ chambers in final whorl.
Test small, 5 chambered, with moderately angular axial periphery, and with an imperforate peripheral margin that is moderately to strongly developed. Aperture a low, umbilical-extraumbilical arch, with a narrow well-defined lip.
Test very small (<130 µm), flattened, with the spiral side nearly flat. Axial periphery rounded with slightly conical chambers. Final whorl with 5-6, chambers that increase very gradually in size. Umbilicus shallow and broad, open to the previous chambers. Aperture umbilical-extraumbilical, broad, low arch with narrow lip.
Specimens which cannot be assigned to established species
Taxonomic discussion: Banner's 1989 study of Globanomalina clarified its taxonomic status, clearly distinguishing the genus from the planispiral Pseudohastigerina, which Loeblich and Tappan (1988) regarded as a junior synonym of this genus. Banner emended the genus to clearly separate it from Pseudohastigerina and discussed its evolutionary relationship with this genus. He, however, regarded Globanomalina as having a microperforate wall with low, bluntly margined perforation pits. His observations appear to be based on poorly preserved specimens with corroded and recrystallized walls. All of the species of Globanomalina included in this atlas are normal perforate. Banner's observation of perforation pits is, however, correct, but as he pointed out, they are not to be confused with a cancellate wall. Globanomalina is herein emended to include the smooth-walled species of the Paleocene, which are members of two distinct lineages, one with an imperforate margin that leads to the carinate species G. pseudomenardii and one with a perforate margin that leads to the planispiral genus Pseudohastigerina. [Olsson et al. 1999]
Catalog entries: Globanomalina, Pseudomenardella
Parent taxon (Globanomalinidae): Hedbergellids - trochospiral, mostly low trochospiral. Apertures of earlier formed chambers remain visible around the umbilicus.
This taxon: Very low trochospiral; 5-6 chambers in final whorl; chamber-shape variable.
Aperture interiomarginal, umbilical-extraumbilical, arch with narrow lip.
Wall smooth, normally perforate, pustules in some species.
Last occurrence (top): in upper part of Lutetian Stage (67% up, 43.4Ma, in Lutetian stage). Data source: Total of range of species in this database
First occurrence (base): within Danian Stage (61.61-66.04Ma, base in Danian stage). Data source: Total of range of species in this database
Plot of occurrence data:
Primary source for this page: Olsson et al. 1999 - Atlas of Paleocene Planktonic Foraminifera, p. 37
Banner, F. T. (1989). The nature of Globanomalina Haque, 1956. Journal of Foraminiferal Research. 19: 171-179. gs Haque, A. F. M. M. (1956). The smaller foraminifera of the Ranikot and the Laki of the Nammal gorge, Salt Range. Memoir of the Pakistan Geological Survey. 1: 1-300. gs Loeblich, A. R. & Tappan, H. (1988). Foraminiferal Genera and Their Classification (Volume I-II). Van Nostrand Reinhold Co., New York. 1-1059. gs Olsson, R. K., Hemleben, C., Berggren, W. A. & Huber, B. T. (1999). Atlas of Paleocene Planktonic Foraminifera. Smithsonian Institution Press, Washington, DC. 1-252. gs
Banner, F. T. (1989). The nature of Globanomalina Haque, 1956. Journal of Foraminiferal Research. 19: 171-179. gs
Haque, A. F. M. M. (1956). The smaller foraminifera of the Ranikot and the Laki of the Nammal gorge, Salt Range. Memoir of the Pakistan Geological Survey. 1: 1-300. gs
Loeblich, A. R. & Tappan, H. (1988). Foraminiferal Genera and Their Classification (Volume I-II). Van Nostrand Reinhold Co., New York. 1-1059. gs
Olsson, R. K., Hemleben, C., Berggren, W. A. & Huber, B. T. (1999). Atlas of Paleocene Planktonic Foraminifera. Smithsonian Institution Press, Washington, DC. 1-252. gs
Globanomalina compiled by the pforams@mikrotax project team viewed: 22-10-2021
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