The tripedal, three-armed species associated with Lieutenant Arex, navigator of the Enterprise in the animated series.
The species is known chiefly through Lieutenant Arex, who served as navigator aboard the Enterprise in The Animated Series. He had orange skin, large yellow eyes, three arms and three legs, a body plan that made him one of the most alien-looking Starfleet officers of the 23rd century.
The name Edosian comes from production material rather than dialogue in the animated series, but later series have made passing references to Edosian flora and fauna. Arex remains the only member of the species seen in any detail on screen.