Quinqueloculina impressa

Quinqueloculina impressa

Reuss, 1851

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

Summary

Quinqueloculina impressa was a benthic miliolid foraminifer with an opaque porcelaneous calcitic test. It lived at or within shallow sea-floor sediment, feeding on bacteria, algae and detrital particles with reticulating pseudopodia.

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 porcelaneous test with chambers wrapped around one another in the characteristic quinqueloculine arrangement and a terminal aperture.

Diagnostic Features

  • Wall porcelaneous and imperforate-looking under reflected light.
  • Chambers follow quinqueloculine coiling, with successive chambers set in changing planes.
  • Test elongate to ovate rather than discoidal.
  • Sutures between the tubular chambers are distinct and impressed.
  • Aperture terminal, commonly with a tooth-like internal 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