portrait

Description:

Katodinium auratum cells are elongated oval from the dorsal side, slightly dorso-ventrally flattened. Length 19 – 30 microns, width 9 – 15 microns. Cingulum beginning at 0.5 – 0.6 of the way down the cell, 2 – 3 microns wide, distal end 2 – 3 microns lower than proximal. Sulcus initially narrow, approximately 1.5 microns, widening towards the posterior of the cell. Apical groove not present. Longitudinal flagellum arising at the anterior end of the sulcus. Nucleus in the epicone, just above the cingulum, round, 6 -10 x 7 – 10 microns. Chloroplasts yellow-green, round to oval, 4 – 6 x 2 –3 microns. Chloroplasts generally positioned peripherally, 10 – 20 per cell. A red stigma, 2 – 4 microns, is present at the origin of the sulcus. Colourless globules are also present in the anterior end of the epicone.