Neornithes Gadow, 1893 - living birds Palaeognathae - palaeognaths see Cohort Palaeognathae Pycraft, 1900 ratites see Subcohort Ratitae Merrem, 1813 Family Rheidae Bonaparte, 1849 - rheas Genus Rhea Brisson, 1760 [monotypic] Rhea americana (Linnaeus, 1758) - greater rhea Rhea americana araneipes Brodkorb, 1938