Parent taxon: Palaeognathae according to K. E. Slack et al. 2006
See also Carroll 1988, del Hoyo et al. 2014, Kampouridis et al. 2020, Lambrecht 1933, Livezey and Zusi 2007, Mayr 2022 and Wetmore 1960
Sister taxa: Aepyornithiformes, Ambiortiformes, Crypturi, Eremopezidae, Lithornidae, Lithornithidae, Medioolithidae, Palaeocursornithiformes, Patagopterygiformes, Ratitae, Remiornithidae, Remiornithiformes, Rheiformes
Subtaxa: Eleutherornithidae Ergilornithidae Geranoididae Palaeotididae Struthionidae
Ecology: ground dwelling herbivore
Distribution:
• Quaternary of Algeria (1 collection), China (1), the Congo-Kinshasa (3), Egypt (2), Ethiopia (1), Georgia (1), Greece (1), Kenya (1), Morocco (2), Niger (2), South Africa (14), Sudan (5), Tanzania (16), Turkmenistan (1), Türkiye (1)
• MN 16 of Greece (1)
• Villafranchian of Hungary (1)
• Pliocene to Pleistocene of China (1), India (1), South Africa (1)
• Pliocene of Egypt (2), Ethiopia (1), Kenya (3), Kyrgyzstan (1), Malawi (1), Moldova (1), Morocco (2), the Russian Federation (2), South Africa (3), Tanzania (3), Türkiye (1), Ukraine (1)
• Turolian of Greece (1)
• Miocene to Pliocene of Kenya (2), South Africa (2)
• Miocene of Algeria (2), Bulgaria (2), China (2), Greece (4), Iraq (1), Kenya (3), Moldova (2), Morocco (1), Namibia (1), South Africa (1), Tunisia (2), Ukraine (6), the United Arab Emirates (1)
• Oligocene of Kazakhstan (1)
• Eocene of France (1), Germany (1), United States (2: Wyoming)
Total: 116 collections including 121 occurrences