Watznaueria martelae

Calolithus martelae Noël, 1965

Watznaueria ovata Bukry, 1969

Elliptical species of Watznaueria are characterised by a relatively large subcircular to elliptical central opening devoid of internal structures. The width of the central opening is consistently less than that of the pelaga.

The shields, as well as the tube cycles, display first-order white interference colours with inclined extinction lines and length-fast (–) elongation. In distal view, the extinction angles are approximately 82° in the distal shield and about 72° in the tube cycles. The locking cycle remains in constant extinction, forming a narrow dim suture between the shield and tube cycle.

Watznaueria martelae differs from Watznaueria fossacincta in possessing a relatively larger central opening (>1.0 µm), whereas the latter has a smaller opening (<1.0 µm). In addition, extinction angles in the tube cycles and in the shields differ significantly between the two species.

Watznaueria martelae is further distinguished from Watznaueria coronata by its sub-circular to elliptical central opening, whereas the latter exhibits a narrow, elongate opening.

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

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.

Noël, D. 1965. Sur les Coccolithes du Jurassique Européen et d'Afrique du Nord. Essai de classification des coccolithes fossiles. Éditions du Centre National de la Recherche Scientifique, Paris. 1-129.