| Hassiavis, Aegialornis, Songlingornithidae|
Archaeotrogon is a prehistoric bird genus. Its remains have been found in the Quercy Phosphorites of France, a geological formation containing Late Eocene and Early Oligocene deposits. Archaeotrogon lived some 30-35 million years ago. Not all species described herein may be valid.
This genus has been placed in a distinct family, the Archaeotrogonidae. The Middle Eocene Hassiavis, a more recently described bird from the famous Messel Pit in Germany, might also belong there. In addition, a somewhat enigmatic fossil in the M. Daniels collection, found in the Early Eocene London Clay appears to belong here too.
As the name implies, Archaeotrogon was initially thought be a prehistoric trogon. However, it is nowadays generally believed that they are not very closely related to these tropical forest birds of our time, but rather convergent. The Archaeotrogonidae actually seem to be Cypselomorphae and related to nightjars and hummingbirds, either as a basal lineage or as a distinct but entirely extinct family. The latter might be more justified than with other indeterminate Cretaceous and Paleogene modern birds: Archaeotrogon is known from a time when the living cypselomorph families were already distinct, yet appears as well highly autapomorphic and the archaeotrogonid lineage seems to go as far back as that of nightjars for example.
†Archaeotrogonidae Wetmore 1926†Hassiavis laticauda Mayr 1998
†Archaeotrogon Milne-Edwards 1892 (Late Eocene/Early Oligocene)
†A. nocturnus Mlíkovský 2002
†A. venustus Milne-Edwards 1892
†A. zitteli Gaillard 1908
†A. cayluxensis Gaillard 1908
†A. hoffstetteri Mourer-Chauviré 1980