Rajiform Locomotion

Rajiform locomotion- a kind of locomotion unique to rays, involves propelling the body with undulating movements of their disc-shaped fins along a vertical plane.

Green Humour for Roundglass Sustain .

In case you missed a similar marine biology class on sharks and the Ampullae of Lorenzini earlier, here it is.

Believe it or not, Sleeper Ray and Sleeper Shark are both actual species (not named so for sleeping in biology class!)