The Axanar are one of the first species encountered by Earth Starfleet, in the Star Trek: Enterprise episode, “Fight or Flight“. The first Axanar they encounter were aboard a freighter that was attacked by a hostile species, and were being harvested for the triglobulin produced by their zymuth glands. The Enterprise narrowly averted conflict when another Axanar ship mistook them for the aggressors.
Triglobulin can be used for medical purposes or as an aphrodisiac by other species. They live to about 400 years old.
There was a famous Battle of Axanar, fought by Fleet Captain Garth of Izar. James T. Kirk was part of the diplomatic peace mission to Axanar, and earned a Palm Leaf of Axanar Peace Mission.
The Axanar became members of the Federation, but it is unknown when.
Axanar (PDF)