Pullenia reussi
Pullenia reussi
Common name
Foraminifer
Fossil group
Foraminifera
Order
Rotaliida
Family
Nonionidae
Genus
Pullenia
Taxonomic status
Accepted
Geological age
Ypresian
Summary
Pullenia reussi was a compact benthic foraminifer with an involute planispiral calcitic test. It lived in the sea-floor microhabitat and gathered bacteria and organic particles with pseudopodia extending from the aperture.
The organism itself was a single cell, but the fossil is its microscopic test. In the 2026 Hampshire Basin study this taxon occurs within the London Clay Formation assemblage used to construct the first foraminiferal zonation of the formation.
Quick Identification
Look for: a smooth, compact planispiral test with inflated chambers and a rounded, almost globular outline, but without the strongly five-lobed profile typical of Pullenia quinqueloba.
Diagnostic Features
- Test compact, involute and planispiral.
- Chambers are inflated and separated by depressed sutures.
- Peripheral outline rounded and smooth rather than sharply keeled.
- Final whorl lacks the strongly regular five-lobed outline characteristic of P. quinqueloba.
- Aperture is a low interiomarginal opening at the base of the final chamber.
Fossil Details
Typical size
Microscopic; generally sub-millimetric.
Fossil material
Foraminiferal Test
Preservation
London Clay foraminiferal tests may be etched, crushed, stained or filled with matrix, and the 2026 study notes poorer preservation in parts of the succession. Fine apertural and sutural characters can disappear with corrosion; incomplete tests should be left at genus or higher rank.
Similar Species
Recorded Fossil Sites
No fossil-site occurrences have yet been recorded for this species.
References
- Hart, M. B.; Alex-Sanders, M. E. A.; Smart, C. W. (2026). Can the distribution of foraminifera locate the Early Eocene Climatic Optimum (EECO) and Middle Eocene Climatic Optimum (MECO) events in the Eocene succession of the Isle of Wight (UK)?. Journal of Micropalaeontology, 45(1), 315–334 View reference
Last Reviewed
20 August 2026
Reviewed by
Sam Harris