Iberomesornis romerali (Aves, Ornithothoraces) reevaluated as an Early Cretaceous enantiornithine

Abstract

Recent cladistic analyses have placed the Early Cretaceous avian, Iberomesornis romerali, outside the enantiornithine radiation at the base of Ornithothoraces. This conclusion is based on erroneous interpretations of the holotypic skeleton, which is shown here to exhibit ten enantiornithine synapomorphies. Revised diagnoses are presented for Enantiornithes and Iberomesornis romerali, which is very close in skeletal form to the Spanish and Chinese enantiornithines Concornis lacustris and Sinornis santensis, respectively.