Nannotax Enabling nannofossil research

Description: Coccolith structure - dome-shaped, formed of layer of crystallites in hexagonal array with the crystalographic c-axis perpendicular to the surface. In LM the rim is bright and cenral part dark.

Coccospheres weakly dimorphic, piriform.

Coccolith form - the coccoliths have simple dome-shaped, with wall showing heaxoganla mesh fabric. Circum-flagellar coccoliths more elevated and with pyramidal central boss.

Remarks:

Size: Liths 2-3 µm long.

Life-cycle association: The association of these holococcoliths with Syracosphaera pulchra has been demonstrated by observation of numerous combination coccospheres, Cros et al. (2000), Geisen et al. (2002). Pirus-type holococcoliths also occur in assocaition with S. pulchra and this has been interpreted as result of pseudo-cryptic speciation (Geisen et al. 2002).

Fossil record: Can be common in well-preserved Quaternary sediments (Crudeli et al. 2006).

Synonym: Calyptrosphaera oblonga Lohmann 1902