Cryothecomonas (cry-oh-theek-oh-moan-ass) is a medium-sized heterotrophic flagellate with two similar flagella emerging from a point just behind the apex of the cell. The ventral surface is grooved (and this causes a slight indentation at the front of the cell). Pseudopodia may arise from the ventral groove. They consume diatoms and other detritus. DIfferential interference microscopy.