View source for Struthioniformes

{{Short description|Order of birds}}
{{Automatic taxobox
| oldest_fossil = Early Eocene
| image = Common Ostrich (Struthio camelus) female ... (51584626132).jpg
| image_caption = ''[[Struthio camelus]]''
| taxon = Struthioniformes
| authority = [[John Latham (ornithologist)|Latham]], 1790
| subdivision = *{{extinct}}''[[Palaeotis]]''
*{{extinct}}''[[Galligeranoides]]''
*{{extinct}}[[Geranoididae]]
*{{extinct}}[[Eogruidae]]
*{{extinct}}[[Ergilornithidae]]
*[[Struthionidae]]
}}
'''Struthioniformes''' is an order of birds with a single extant family, [[Struthionidae]], containing the [[ostrich]]es. Several other extinct families are known, spanning across the Northern Hemisphere, from the Early [[Eocene]] to the early [[Pliocene]], including a variety of [[Flightless bird|flightless]] forms like the [[Palaeotididae]], [[Geranoididae]], [[Eogruidae]] and [[Ergilornithidae]], the latter two thought to be closely related to Struthionidae.

== Evolutionary history ==
According to Mayr and Zelenkov (2021), all Struthioniformes are united by the following characters: "a very long and narrow [[tarsometatarsus]] with short trochleae for the second and fourth toes, a tubercle next to the pons supratendineus on the distal end of the [[tibiotarsus]], as well as a shortening of all non-ungual [[phalanges]] of the fourth toe except for the proximal one" All known members of the group are thought to have been flightless. Struthioniformes were widely distributed in the Northern Hemisphere during the [[Eocene]], including [[Paleotididae]] from Europe, and [[Geranoididae]] from North America, and [[Eogruidae]] and [[Ergilornithidae]] in Asia.<ref name=":0" /> The discovery of ''Lumbreornis'', belonging to either Paleotididae or Geranoididae, suggests that Struthiorniformes probably also inhabited South America during the Eocene.<ref>{{Cite journal|last1=Bertelli |first1=S. |last2=Giannini |first2=N. P. |last3=García-López |first3=D. A. |last4=Deraco |first4=V. |last5=Babot |first5=J. |last6=Del Papa |first6=C. |last7=Armella |first7=M. A. |last8=Herrera |first8=C. |last9=Mayr |first9=G. |year=2024 |title=The first Eocene bird from Northwestern Argentina  |journal=Publicación Electrónica de la Asociación Paleontológica Argentina |volume=24 |issue=2 |pages=78–89 |doi=10.5710/PEAPA.31.05.2024.511 |doi-access=free }}</ref> Ergilornthidae would persist in Asia into the Early [[Pliocene]], while its sister group [[Struthionidae]] likely originated from Asia.<ref name=":0" /> Ostriches first appeared in Africa during the early Miocene, around 21 million years ago, before dispersing into Eurasia during the late Miocene, beginning around 12 million years ago.<ref>{{Cite journal |last1=Widrig |first1=Klara |last2=Field |first2=Daniel J. |date=February 2022 |title=The Evolution and Fossil Record of Palaeognathous Birds (Neornithes: Palaeognathae) |journal=Diversity |language=en |volume=14 |issue=2 |page=105 |doi=10.3390/d14020105 |issn=1424-2818|doi-access=free }}</ref>

== Taxonomy ==
After Mayr, and Zelenkov (2021)<ref name=":0">{{Cite journal |last1=Mayr |first1=Gerald |last2=Zelenkov |first2=Nikita |date=2021-11-13 |title=Extinct crane-like birds (Eogruidae and Ergilornithidae) from the Cenozoic of Central Asia are indeed ostrich precursors |url=https://academic.oup.com/auk/article/doi/10.1093/ornithology/ukab048/6338403 |journal=Ornithology |language=en |volume=138 |issue=4 |article-number=ukab048 |doi=10.1093/ornithology/ukab048 |issn=0004-8038|doi-access=free }}</ref>

* [[Palaeotididae]] (Early mid-Eocene, Europe)
** ''[[Palaeotis]]''
** ''[[Galligeranoides]]''
* [[Geranoididae]] (Early-mid Eocene, North America)
* Unnamed clade
** [[Eogruidae]] (monotypic)
*** ''[[Eogrus]]'' (mid-Late Eocene, Asia)
** ''[[Sonogrus]]'' (late Eocene, Asia)
** Unnamed clade
*** ''[[Proergilornis]]'' (late Eocene, Mongolia)
*** Unnamed clade
**** [[Ergilornithidae]] (Late Eocene-Early Pliocene, Asia)
**** [[Struthionidae]] (Early Miocene-Recent, Afro-Eurasia)

== Gallery ==
{{gallery|File:Palaeotis weigelti 2.jpg|Skeleton of ''[[Palaeotis weigelti]]''|File:Ergilornis.jpg|Life restoration of ''[[Ergilornis]]''|||||width=300|height=360}}

==References==
{{reflist}}

{{Taxonbar|from1=Q840849}}
{{Authority control}}

[[Category:Struthioniformes| ]]
[[Category:Bird orders]]
[[Category:Taxa named by John Latham (ornithologist)]]
[[Category:Ratites]]