(Reuters) - Texas executed a Houston man on Thursday convicted in the 1988 killing of a teenager and her toddler cousin, a prison spokesman said.

Preston Hughes, 46, was convicted of stabbing to death 15-year-old Shandra Charles and her 3-year-old cousin, Marcell Taylor, in a vacant field near his apartment complex.

Hughes was executed at 7:52 p.m. Central Time. He was the 40th inmate executed in the United States this year and the 15th in Texas.

(Reporting by James B. Kelleher; Editing by Eric Walsh)