A new specimen of the Early Eocene Masillacolius brevidactylus and its implications for the evolution of feeding specializations in mousebirds (Coliiformes)

A new skeleton of the Early Eocene stem group mousebird Masillacolius brevidactylus is described, which for the first time provides information on the skull morphology of this unusual coliiform species. Notably, the mandible exhibits long, blade-like retroarticular processes, which were previously only known from two distantly related taxa of stem group Coliiformes. An assessment of the evolutionary significance of these structures depends on...