New remains of the very small cuckoo,Chambicuculus pusillus (Aves, Cuculiformes, Cuculidae) from the late Early/early Middle Eocene of Djebel Chambi, Tunisia

A very tiny cuckoo, Chambicuculus pusillus, was recently described after a few fragments of tarsometatarsi from the late Early/early Middle Eocene of Djebel Chambi, Tunisia. New remains, notably a coracoid, confirm the attribution of this genus to the family Cuculidae. This coracoid shows a very elongate and strap-like processus procoracoideus. This morphological feature is present in some recent or extinct taxa but it is more developed in the family Cuculidae. The characteristics of the coracoid and tarsometatarsi show that Chambicuculus is morphologically more advanced over the other stem cuculids described in Europe and North America. Chambicuculus is the oldest Cuculidae known so far.