black and white portrait

Description:

Dinema (die-knee-ma) platysomum (Skuja, 1939) Lee and Patterson, 2000. Cells are elliptical, 20 to 32 microns long, flattened and flexible. There are about 20 pellicular striations on ventral and dorsal faces of the cell. The ventral striations are more distinct than the dorsal ones. The two flagella are unequal in length. The anterior flagellum is slightly thickened, is about 1.2 times the length of the cell and sweeps from side to side. The trailing posterior flagellum is thicker and is most strongly developed proximally. It lies in a ventral groove and is about 2 to 2.5 times the length of the cell. The flagellar pocket is located in the left side of the cell and the large elliptical nucleus is located on the right half in the middle of the cell. The chisel-shaped ingestion apparatus may be easily seen. The cells occasionally stop and jerk when changing direction and then move again. The cells contained diatoms as food. Rarely observed.