Set number: 4601

  • Pedinocyclus larvalis VR 30807 1
  • Pedinocyclus larvalis VR 30808 2
  • Pedinocyclus larvalis VR 30809 3
  • Pedinocyclus larvalis VR 30810 4
  • Pedinocyclus larvalis VR 30811 5
  • Pedinocyclus larvalis VR 30812 6
  • Pedinocyclus larvalis VR 30813 7
  • Pedinocyclus larvalis VR 30814 8
  • Pedinocyclus larvalis VR 30815 9
  • Pedinocyclus larvalis VR 30816 10
  • Pedinocyclus larvalis VR 30817 11
  • Pedinocyclus larvalis VR 30818 12
  • Pedinocyclus larvalis VR 30819 13
  • Pedinocyclus larvalis VR 30820 14
  • Pedinocyclus larvalis VR 30821 15
  • Pedinocyclus larvalis VR 30822 16
  • Pedinocyclus larvalis VR 30823 17
  • Pedinocyclus larvalis VR 30824 18
  • Pedinocyclus larvalis VR 30825 19
  • Pedinocyclus larvalis VR 30826 20
  • Pedinocyclus larvalis VR 30827 21
  • Pedinocyclus larvalis VR 30828 22
  • Pedinocyclus larvalis VR 30829 23
  • Pedinocyclus larvalis VR 30830 24
    10µm
Pedinocyclus larvalis, Middle Eocene, DSDP Leg 39, Sites 356, Sào Paulo Plateau, South Atlantic Ocean
Final Epithet
Pedinocyclus larvalis (Bukry & Bramlette , 1969b) Loeblich & Tappan, 1973
Basionym

Leptodiscus larvalis Bukry & Bramlette, 1969b

Description

Pedinocyclus was originally defined as comprising circular coccoliths constructed of a single, thin, nearly flat shield composed of slightly inclined to radial elements that are not clearly imbricate, and surrounding a relatively small central opening. The diagnosis therefore emphasises the simple single-shield construction, weak or absent imbrication of the elements, and the small central opening.

A limited number of specimens have been examined using the mobile mount. Most specimens encountered were incomplete or broken, and it remains possible that a proximal shield, if originally present, has been lost during preservation or preparation. The available material is therefore insufficient to confirm whether Pedinocyclus is genuinely constructed of a single shield. Further specimens will be sought to clarify its construction.

Remarks

Originally described as Leptodiscus larvalis Bukry & Bramlette, 1969, the species could not remain in Leptodiscus because that generic name was preoccupied by the dinoflagellate Leptodiscus Hertwig, 1877. Bukry & Bramlette (1971) therefore introduced the new genus Pedinocyclus, designating Leptodiscus larvalis as its type species, but they did not formally establish the new combination Pedinocyclus larvalis. The combination Pedinocyclus larvalis (Bukry & Bramlette, 1969) Loeblich & Tappan, 1973 was subsequently introduced by Loeblich & Tappan (1973).

References

Bukry, D., Bramlette, M. N., 1969b. Some new and stratigraphically useful calcareous nannofossils of the Cenozoic. Tulane Studies in Geology 7, 131-142.

Bukry, D. & Bramlette, M. N. 1971. Validation of Pedinocyclus and Quinquerhabdus new calcareous nannoplankton genera. Tulane Studies in Geology and Paleontology. 8: 122-122.

Loeblich, A. R. & Tappan, H. 1973. Annotated index and bibliography of the calcareous nannoplankton VII. Journal of Paleontology. 47(4): 715-759.