HOACIN (Opisthocomus do), The word Opisthocomus comes from the Greek opisthe, "behind" and komes, "hair", . opisthomiform bird, the only representative of the genus Opisthocomus and the family Opisthocomidae. It is a peculiar tropical bird that inhabits the swampy areas that surround the Amazon and Orinoco rivers, in South America. Some synonyms, words or similar expressions may be hoacin, hoatzin, chenchena 40, in the plains 41, , pava serere 40 , in bolivia 41 , , shansho 40 , in peru 41 , , guacharaca de agua 40 , in venezuela 41 , , pava hedionda 40 , in colombia 41 ,