Siren skull head?

Can someone tell me how to get the head for the siren where it’s a skull and its glowing blue and u can see the skin on their head pulled down to their neck???

This one?

It’s found in the head hunter pack Mad Moxxi and the Wedding Day Massacre.
You can get it by completing the mission A Match Made On Pandora with Maya or via random drop from the boss.

I like that head and the Dolphins are badass skin from the son of crawmerax dlc