A new species in the genus Agestrata Eschscholtz, 1829 is described from Myanmar. The new taxon, Agestrata fortii n. sp., is markedly different from the other members of the genus. Further to the uniform turquoise-cerulean blue color of the integument, A. fortii displays a unique and highly derived aedeagal structure, metacoxae lacking an acute posterolateral angle, and broadly depressed abdominal sternites. Even when taken individually, these character states distinguish A. fortii from all known Agestrata species.