The whale has a series of 56–100 pleats or grooves along the bottom of the body that run from the tip of the chin to the navel that allow the throat area to expand greatly during feeding. It has a curved, prominent dorsal fin that ranges in height from (usually ) and averages about , lying about three quarters of the way along the back. Its flippers are small and tapered and its tail is wide, pointed at the tip, and notched in the centre.