Calcidiscus tropicus

Description

  • Citation: 
    Calcidiscus tropicus Kamptner, 1956 sensu Gartner, 1992

    Description: Species of Calcidiscus producing circular coccoliths with open central-area, 7-10μm.

    Remarks: Not always separated from C. leptoporus. Miocene forms often have a bicyclic proximal shield, in Pliocene forms a coarse grill is often visible in central opening. Larger forms (>10µm) are separated as C. macintyrei, possibly evolves into C. quadriperforatus.

    Range: NN4 to 19.

    4-19tropicus.JPG 4-16tropicus.JPG 4-18tropicus.JPG 4-20tropicus.JPG 4-17tropicus.JPGCtrop191-16NN16.JPGCtrop190-29NN16.JPG

    Variants;

    • C. leptoporus ssp centrovalis (Stradner and Fuchs, 1980) Perch-Nielsen, 1984 - similar to C. tropicus but sub-circular;
    • C. carlae (Lehotayova and Priewalder, 1978) Janin, 1992 [Cycloperfolithus] - Paratethyan form, with fine grill in central-area, and bicyclic proximal shield.

     

Images

  • 4-16tropicus.JPG
  • 4-17tropicus.JPG
  • 4-18tropicus.JPG
  • 4-20tropicus.JPG
  • 4-19tropicus.JPG
  • Ctrop191-16NN16.JPG
Scratchpads developed and conceived by: Vince Smith, Simon Rycroft & Dave Roberts