Paulinella
Paulinella chromatophora, dividing

 

 

Genus Paulinella Lauterborn, 1895

 

Diagnosis: shell pyroid or broad-elliptical, not compressed, composed of siliceous, rectanguloid plates with slightly rounded, scarcely overlapping borders, arranged in circumferential longitudinal rows; in apertural view the plates form a counter-clockwise spiral, with one pentagonal scale at the aboral pole. Pseudostome small. Plasmabody with usually two sausage-like endosymbionts of cyanobacterial origin. Filopodia, usually fast moving.

 

Paulinella
Paulinella
Granulated nucleus, after division, and empty shell, stacked image