Charlotte Mayfield is the Vice President of Farrow-Marshall Aeronautics, and also a Trust agent, who was taken over by the Goa'uld Athena sometime after Ba'al came to Earth.
She was questioned by Lt. Colonel Samantha Carter about the disappearance of Alex Jameson, but was not cooperative. (SG1: "Ex Deus Machina")
She had attempted to probe Vala Mal Doran's mind in an attempt to get information on the Clava Thessara Infinitas, but that eventually failed after US officers attacked a safehouse and Vala escaped. She was possibly the last remaining Goa'uld on Earth. (SG1: "Memento Mori")