Hybrid species, part human and part Spartoi.
The Spartoi are a cousin race to the Shi'ar. While they are not necessarily allies, they have attempted a union in the past and do not consider one another to be enemies. They hail from the planet Spartax and from there the people built an empire consisting of hundreds of worlds.
The Spartoi Empire is ruled by an Emperor and guided by a Council of Ministers. The Spartoi are very long-lived by Earth standards, J'son of Sparta being well over 100 years old and not yet considered middle aged.