Hoatzin - Taxonomy, Systematics and Evolution

Taxonomy, Systematics and Evolution

The Hoatzin was originally described by German zoologist Statius Müller in 1776. It is arguably the most enigmatic living bird in regard to its phylogenetic relationships. No satisfying evolutionary hypothesis has been proposed, and the situation has become worse with the availability of DNA sequence data.

There has been much debate about the Hoatzin's relationships with other birds. Because of its distinctness it has been given its own family, the Opisthocomidae, and its own suborder, the Opisthocomi. At various times, it has been allied with such taxa as the tinamous, the Galliformes (gamebirds), the rails, the bustards, seriemas, sandgrouse, doves, turacos and other Cuculiformes, and mousebirds. Altogether, it has been most frequently suggested to be related to Galliformes, turacos, or the anis (New World cuckoos).