The Arfak astrapia (Astrapia nigra) is a species of astrapia, a group of birds found in the Paradiseidae family of the birds-of-paradise.
In the wild, the bird has hybridised with the black sicklebill creating offspring that were once considered a distinct species, Elliot's sicklebill "Epimachus ellioti". While some ornithologists still believe that this bird is a distinct species, possibly critically endangered or even extinct, many now think it was a hybrid between the two species.
The Arfak astrapia is the third largest of its genus, being approximately 76 cm long, including the tail. The male has a black head with a bluish-purple sheen, or iridescence, an elongated jet-black nape crests extending up along the sides of the up to the eyes on each side, a shiny, metallic greenish-yellow cape from the mantle up to the nape, very black, dense and elongated upper breast feathers, and an almost exaggeratedly long tail almost two times the length of its body. The female is less appealing, being dark brown over most of its body and a blackish head, and sporting much shorter tail feathers. The female is also exceptionally shorter than the male.