The African blue flycatcher or blue-crested flycatcher (Elminia longicauda) is a species of bird in the family Stenostiridae from western and central Sub-Saharan Africa. The African blue flycatcher is a dainty, pale, bright blue flycatcher with a short crest and long tail. The entire upper parts and tail are bright blue, shading between blue and cyan, with black lores and black flight feathers edged with blue, the underparts are greyish blue fading to whitish on the belly. The bill and legs are black. Juveniles are duller with faint greyish spotting on the head and wing coverts. It measures 15–18 cm (5.9–7.1 in) in length and weighs 7–12 g (0.25–0.42 oz). The African blue flycatcher occurs from Mauritania, Senegal and Gambia east discontinuously to Kenya and south through the eastern Democratic Republic of Congo to northern Angola. Its natural habitats are moist lowland forests, mangrove forests, gallery forest, montane forests, gardens, wooded farmland and moist savanna. The African blue flycatcher forages rather gracefully with a fanned tail and half open wings among leaves, as well as occasionally foraging on the ground and flycatching.