NBA's Trevor Ariza -- Floss Like An Egyptian ... Drops $12k On Anubis Chain

Diamond studded King Tut is out, diamond studded Anubis is wayyy in -- so says NBA star Trevor Ariza ... who just dropped $12,000 on a brand new jackal-headed gold piece ... TMZ Sports has learned.

The Rockets star hit up Johnny's Custom Jewelry in Houston looking for something cool -- and according to the brother of the owner, Zo, asked for a piece with an ancient Egyptian theme.

But Zo says Ariza was tired of seeing King Tut everywhere ... and wanted something a little more original. So he crafted an 18-karat design of Anubis -- a god who ushered souls into the afterlife.

Bonus Egyptian Joke -- What's a mummy's favorite kind of music? Wrap.