Cinsin bilinen üç türü bulunmaktadır.
- ^ Zelenkov, Nikita V.; Lavrov, Alexander V.; Startsev, Dmitry B.; Vislobokova, Innessa A.; Lopatin, Alexey V. (4 Mart 2019). "A giant early Pleistocene bird from eastern Europe: unexpected component of terrestrial faunas at the time of early Homo arrival". Journal of Vertebrate Paleontology (İngilizce). 39 (2): e1605521. doi:10.1080/02724634.2019.1605521. ISSN 0272-4634. 11 Nisan 2021 tarihinde kaynağından arşivlendi. Erişim tarihi: 1 Ağustos 2021.
- ^ Kampouridis, Panagiotis; Michailidis, Dimitrios; Kargopoulos, Nikolaos; Roussiakis, Socrates; Theodorou, Georgios (16 Haziran 2020). "First description of an ostrich from the late Miocene of Kerassia (Euboea, Greece): remarks on its cervical anatomy". Historical Biology. 0 (0): 1-8. doi:10.1080/08912963.2020.1779252. ISSN 0891-2963.