Yes. His race go through "morphs". Originally he was a female (which has different meaning in their culture) Aurash. Then he took the king morph to become Auryx. Then when he killed Akka to gain direct access and power from the Deep he became Oryx (that one possibly came only as a representation of his new power, as opposed to a morph).

Aurash was oryx in pre worm stage. Once he met the worms and became one with akka, he became Auryx, and once he stole from the deep and learned sword logic and taken powers, he became Oryx, Taken King, King of the Final Shape, and a couple other titles When he becomes one with Akka, he morphs into his king form, and into a hive, not a krill anymore. He is part of the darkness and lives longer now

She became a man