On the abdomen are swimming appendages called pleopods, and the body ends in a tail fan.
The abdomen of the lobster includes swimming legs and a tail fan.
It also has a ducted tail fan in the rear.
The adult male's tail fan will be all the same length.
The uropods may work in concert with the telson to form a "tail fan".
Together, the telson and uropods form a splayed tail fan.
If a shrimp is alarmed, it can flex the its tail fan in a rapid movement.
The ganglia here also receive sensory input from the sensitive hairs on the tail fan.
When flexion occurs, only the first three segments flex and the tail fan is not directed under the body and forward but rather straight down.
The base of the tail fan has pale spots and the antennae are a uniform colour.