Arex

Arex was an Edoan officer on active duty in the 23rd and 24th centuries.


 * In Pocket Books continuity, Arex na Eth was a Triexian, a species easily confused with the Edoans.

Lieutenant Arex was a navigations officer who transferred to the USS Enterprise during the latter part of James T. Kirk's first five-year mission. 

Absolute Horizon
Arex left the Enterprise before the end of the mission, citing "family obligations." In truth, he was suffering from a degenerative illness -- particular to his species -- that Dr. Leonard McCoy was unable to treat. By the time Arex returned to his homeworld, Edos, one of his arms was completely anemic.

Orion Press
Arex was also chief navigator of the Enterprise, after its refit, until 2275.

He briefly served aboard the USS Yorktown in 2276, but transferred to the Reliant -- commanded by Captain Clark Terrell -- until the mid-2280s.

By 2292, Arex had been promoted to captain and was commanding officer of the USS Repulse. During a battle against Tholians at Alpha Tucanae, he sustained two broken arms. (Orion Press: "A Klingon Holiday", " Ad Astra Per Aspera ", Liberation from Hell, Chekov's Enterprise)