Parent taxon: Palaeognathae according to J. F. Clements et al. 2017
See also Acosta Hospitaleche and Picasso 2022, Carroll 1988, Livezey and Zusi 2007 and Mayr 2022
Sister taxa: Aepyornithiformes, Ambiortiformes, Crypturi, Eremopezidae, Lithornidae, Lithornithidae, Medioolithidae, Palaeocursornithiformes, Patagopterygiformes, Ratitae, Remiornithidae, Remiornithiformes, Struthioniformes
Subtaxa: Rheidae
Ecology: ground dwelling carnivore
Distribution:
• Quaternary of Argentina (11 collections), Bolivia (1), Brazil (2)
• Pliocene of Argentina (3)
• Huayquerian of Argentina (3)
• Miocene to Pliocene of Argentina (1)
• Miocene of Argentina (8)
• Neogene of Argentina (1)
• Eocene to Miocene of Argentina (1)
• Eocene of Brazil (1)
Total: 32 collections including 35 occurrences