Sailor

The Sailors are an aquatic, crustacean-like species from Orion's Arm. They are known for the fact that they are natural, biological sailboats.

Homeworld
Their homeworld is not specified in the Encyclopedia Galactica, but it likely has large oceans, or possibly is an entirely ocean world.

Physiology
The Sailors range in size from about a meter to two meters in length. They are air breathers, like dolphins or porpoises, and fill much the same ecological niche.

Sailing
The Sailors have soft bodies, covered in a hard shell filled with various tanks and chambers that can be filled with water and air or emptied of it to control ballast. Their main form of locomotion is in the form of 3 large fins on their back which act like natural ship sails. A complex muscle and tendon system allow the Sailor to turn and orient the sails to catch the wind or to collapse them when resting or in rough weather. They can fill their shells with water and collapse their sails and sink to the bottom to rest or swim slowly, as a water-breather.

They have a series of fins along their underside to control direction and swim in calm seas.

It is not specified whether or not they are sapient.