Noov

Noov was a Zaranite who handled the night shift on the SS Clydesdale. Since Noov breathed fluorine and needed a full facemask and fluorine supply to come out of his quarters, he tended to keep to himself except when he was on duty.

When the Clydesdale was intercepted by the USS Ventus, the Starfleet crew left him on board the Clydesdale because of his fluorine needs. He was able to help rescue everyone from the Ventus once Mike Harper came up with a plan. ("Busted" [TOS])