Watznaueria biporta

Watznaueria biporta Bukry, 1969

The shields display first-order yellowish-white interference colours, while the tube cycles exhibit white interference colours; all structures display inclined extinction lines and length-fast (–) elongation. In distal view, the extinction angles are approximately 80° in the shields and 72° in the tube cycles. Variation in the orientation of extinction lines between the tube cycles and the shield facilitates identification of the narrow outer tube cycle, in combination with observations under phase-contrast and bright-field illumination.

Large (>6.0 µm), subcircular to elliptical species of Watznaueria, characterised by a wide inner tube cycle bearing two pores aligned along the long axis of the placolith. The narrow outer tube cycle is readily observed under phase-contrast and bright-field illumination.

Watznaueria biporta differs from Watznaueria cynthae primarily in pore arrangement: in Watznaueria biporta, the pores are aligned along the long axis of the placolith, whereas in Watznaueria cynthae they are diagonally aligned.

Bukry, D. 1969. Upper Cretaceous coccoliths from Texas and Europe. University of Kansas Paleontological Contributions, Articles 51 (Protista 2): 1-79.