Quinqueloculina carinata

Quinqueloculina carinata

d'Orbigny, 1826

Common name Foraminifer
Fossil group Foraminifera
Order Miliolida
Family Hauerinidae
Genus Quinqueloculina
Taxonomic status Accepted
Geological age Ypresian

Summary

Quinqueloculina carinata was a benthic miliolid foraminifer with a porcelaneous, chambered calcitic test. It lived on or within shallow sea-floor sediment and used pseudopodia to collect bacteria, algae and detrital particles.

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: an elongate quinqueloculine test with angular chamber margins forming a conspicuous keel and a terminal aperture at the end of the final chamber.

Diagnostic Features

  • Wall porcelaneous and apparently imperforate.
  • Chambers arranged in quinqueloculine coiling around the test axis.
  • Test elongate with distinctly angular chamber margins.
  • A pronounced carina/keel gives the test a sharper-edged cross-section than Q. impressa.
  • Aperture terminal and commonly furnished with a tooth-like projection.

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