Crepidolithus perforatus

(Medd, 1971) Grün & Zweili, 1980 Jan 31, 2026

Set number: 2987

  • Crepidolithus perforatus 10988 1
  • Crepidolithus perforatus 10990 2
  • Crepidolithus perforatus 10992 3
  • Crepidolithus perforatus 10995 4
  • Crepidolithus perforatus 10989 5
  • Crepidolithus perforatus 10991 6
  • Crepidolithus perforatus 10993 7
  • Crepidolithus perforatus 10994 8
    10µm
Crepidolithus perforatus, Oxfordian, DSDP Leg 76, Site 534, Blake-Bahama Basin, Atlantic Ocean
Final Epithet
Crepidolithus perforatus (Medd, 1971) Grün & Zweili, 1980
Basionym

Millbrookia perforata Medd, 1971

Optical Properties

In plan view under crossed polars, the wall exhibits weak birefringence, showing greyish-white interference colours and length-slow (+) elongation when a gypsum plate is inserted into the light path.

Remarks

Species of Crepidolithus are constructed of a single wall surrounding a central area spanned by a delicate, non-permanent proximal grill, which is often absent due to adverse palaeoenvironmental conditions. The width of the wall and the size of the central area vary greatly.

References

Grün, W. & Zweili, F. 1980. Das kalkige Nannoplankton der Dogger-Malm-Grenze im Berner Jura bei Liesberg (Schweiz). Jahrbuch der Geologischen Bundesanstalt. 123: 231-341.

Medd, A. W. 1971. Some Middle and Upper Jurassic Coccolithophoridae from England and France. In: Farinacci, A. (Ed.) Proceedings of the Second Planktonic Conference, Roma 1970. Edizioni Tecnoscienza, Roma 2: 821-844.

Taxonomy
Crepidolithus
Biostratigraphy
  • Phanerozoic
    • Mesozoic
      • Jurassic
        • Late Jurassic
          • Malm
            • Kimmeridgian
              • Early Kimmeridgian
        • Middle Jurassic
          • Dogger
            • Callovian
              • Early Callovian
Stratigraphic Range
Early Callovian - Early Kimmeridgian
Age (Ma)
164.50 - 152.98
Holotype
Crepidolithus perforatus 10991

Millbrookia perforata Medd, 1971

Oxfordian

Millbrook section, near Ampthill, Bedfordshire, England.