The Kioea (Chaetoptila angustipluma), is an extinct species of Hawaiian bird that became extinct around 1859. The kioea was in decline even before the discovery of Hawaiʻi by Europeans. Even native Hawaiians are seemingly unfamiliar with this bird. The feathers of the kioea were not used in Hawaiian featherwork, nor is it mentioned in any chants or legends. Only four specimens exist in museums. The cause of its extinction is unknown.