The Loten's sunbird, long-billed sunbird or maroon-breasted sunbird, (Cinnyris lotenius) is a sunbird endemic to peninsular India and Sri Lanka. Its long bill distinguishes it from the similar purple sunbird that is found in the same areas and also tends to hover at flowers. Like other sunbirds, it feeds on small insects and builds characteristic hanging nests. The species is named after a colonial Dutch governor of Ceylon, Joan Gideon Loten.