Acrodipsas illidgei is an endangered butterfly inhabiting mangrove forests in southeasternQueensland, Australia. Concern over the effects of mosquito control activities prompted a broad-scale surveyfor the species at Coomera Island, in southeastern Queensland. The butterfly was recorded on the edge of anold-growth mangrove forest in close proximity to mosquito control runnels. Other forms of mosquito control atCoomera Island are unlikely to impact on the species because of the mode of action of larvicides used and thefact larvae occur within ant colonies formed in hollow stems and branches of mangrove trees. Further studiesare required to more fully understand the relationships between mosquito control activities and the populationdynamics of endangered species such as A. illidgei.