Pedinocyclus larvalis

Leptodiscus larvalis Bukry & Bramlette, 1969b

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.

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).

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.