Euryceros prevosti; Print; Helmet vanga; The helmet vanga (Euryceros prevostii) is a distinctive-looking bird of the vanga family; Vangidae; and is classified in its own genus; Euryceros. It is mainly blue-black; with rufous wings and a huge arched blue bill. It is restricted to lowland and lower montane rainforests of northeastern Madagascar. Its diet is composed of invertebrates; predominantly insects. The species is threatened by habitat loss.; 1838