The Bright Oakblue (Arhopala madytus) is a butterfly of the Lycaenidae family. It is found in New Guinea and adjacent islands (Aru, Ambon, Waigeu, from West Irian to Papua, Woodlark and the Louisiades) and the north-east coast of Queensland The wingspan is about 40 mm. The larvae feed on Terminalia catappa, Terminalia melanocarpa, Terminalia sericocarpa and Hibiscus tiliaceus. They are attended by the ant species Oecophylla smaragdina.