Karlodinium ballantinum Salas 2008

3.1.3 Karlodinium ballantinum Salas 2008 ( Figure 4 View Figure 4 )

The cells were solitary, more or less oval in ventral view, 14 – 18 μm long, and 10 – 13 μm wide, with a length to width ratio of about 1.4. The cingulum was equatorial, and the epicone and hypocone were both hemispherical and nearly equal in size ( Figure 4A – D, L View Figure 4 ). The cingulum originated at the longitudinal axis of the cell, descended, and displaced about two cingular widths or 25 – 30 % of the cell length. The sulcus was sigmoid; it formed a short finger-like projection onto the epicone and continued a narrow, oblique connection between the two ends of the cingulum before fading and becoming wider posteriorly ( Figure 4A – D View Figure 4 ). A short apical groove was linear and extended across the apex and briefly down the dorsal epicone ( Figure 4B – E View Figure 4 ). In squashed cells, a pattern of knob-like structures lining the lower margin of the cingulum was discerned ( Figure 4G View Figure 4 ). No ventral pore was observed. The nucleus was located in the central part of the cell, close to the dorsal side ( Figure 4H – J View Figure 4 ). Numerous (8 – 19) irregularly shaped chloroplasts with internal pyrenoids were present ( Figure 4K View Figure 4 ). Cell division occurred at the motile stage ( Figure 4F View Figure 4 ).