Escivs are up to 3mm long, and 2mm wide.
Thick carbonate armour surrounds their bodies. They have six cilia and a long tail like other Rhombites.
Rhombites reproduce asexually, laying a small sac containing five to ten eggs. This floats in the plankton.
These hatch to produce smaller Desevs, which grow up rapidly. Desevs usually live three weeks if not eaten, and reproduce once every five days.