Unenlagiidae

{{Short description|Extinct family of dinosaurs}} {{automatic taxobox | name = Unenlagiids | fossil_range = {{fossilrange/linked|Late Cretaceous}} | image = Austroraptor Reconstruction.jpg | image_caption = Life reconstruction of ''[[Austroraptor]] cabazai'' | taxon = Unenlagiidae | authority = Bonaparte, 1999 | type_species = {{extinct}}''[[Unenlagia comahuensis]]'' | type_species_authority = Novas & Puerta, 1997 | subdivision_ranks = Subfamilies | subdivision = *{{extinct}}[[Halszkaraptorinae]]? *{{extinct}}[[Unenlagiinae]] | synonyms = * '''Unenlagiinia'''? <small>Brum et al., 2021</small> }}

'''Unenlagiidae''' is a proposed family of [[Paraves|eumaniraptoran paravian]]s that includes the subfamilies [[Unenlagiinae]] and possibly [[Halszkaraptorinae]]. Fossils of both subfamilies have been found in both [[Gondwana]]n and [[Laurasia]]n deposits. The biology of the group suggests that some members were semiaquatic specialists.<ref name="Cauetal2017"/>

== Classification == The family Unenlagiidae traditionally includes the same members as the previously named subfamily of [[Dromaeosauridae]], [[Unenlagiinae]], so Unenlagiidae was often seen as a synonym of Dromaeosauridae. However, since the 2010s, there have been subsequent studies that have questioned this placement, necessitating the revival of the family name. Some have placed unenlagiids as outside Dromaeosauridae, being the sister taxon or closely related to [[Avialae]],<ref name=avianancestry>{{cite book|author=Federico L. Agnolín and Fernando E. Novas |year=2013 |title=Avian ancestors. A review of the phylogenetic relationships of the theropods Unenlagiidae, Microraptoria, ''Anchiornis'' and Scansoriopterygidae |pages=1–96 |doi=10.1007/978-94-007-5637-3 |series=SpringerBriefs in Earth System Sciences |isbn=978-94-007-5636-6|s2cid=199493087 }}</ref><ref name=Overoraptor>{{cite journal |author1=Matías J. Motta |author2=Federico L. Agnolín |author3=Federico Brissón Egli |author4=Fernando E. Novas |year=2020 |title=New theropod dinosaur from the Upper Cretaceous of Patagonia sheds light on the paravian radiation in Gondwana |journal=The Science of Nature |volume=107 |issue=3 |article-number=24 |doi=10.1007/s00114-020-01682-1 |pmid=32468191 |bibcode=2020SciNa.107...24M |s2cid=218913199 |hdl=11336/135530 |hdl-access=free }}</ref> while others have placed the newly recognized [[Halszkaraptorinae|halszkaraptorines]] in the family, as basal [[Deinonychosauria|deinonychosaurs]] outside Dromaeosauridae and [[Troodontidae]].<ref name="Hartmanetal2019">{{cite journal |last1=Hartman |first1=Scott |last2=Mortimer |first2=Mickey |last3=Wahl |first3=William R. |last4=Lomax |first4=Dean R. |last5=Lippincott |first5=Jessica |last6=Lovelace |first6=David M. |title=A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight |journal=PeerJ |date=2019 |volume=7 |article-number=e7247 |doi=10.7717/peerj.7247 |pmid=31333906 |pmc=6626525 |doi-access=free }}</ref> Other recent studies supported the traditional placement of Halszkaraptorinae and Unenlagiinae in Dromaeosauridae, forming no distinct clade.<ref name="Cauetal2017">{{cite journal|last1=Cau|first1=A.|last2=Beyrand|first2=V.|last3=Voeten|first3=D.|last4=Fernandez|first4=V.|last5=Tafforeau|first5=P.|last6=Stein|first6=K.|last7=Barsbold|first7=R.|last8=Tsogtbaatar|first8=K.|last9=Currie|first9=P.|last10=Godrfroit|first10=P.|date=6 December 2017|title=Synchrotron scanning reveals amphibious ecomorphology in a new clade of bird-like dinosaurs|journal=[[Nature (journal)|Nature]]|volume=552|issue=7685|pages=395–399|doi=10.1038/nature24679|pmid=29211712|bibcode=2017Natur.552..395C|s2cid=4471941}}</ref><ref name=Cau2020>{{Cite journal|last=Cau|first=Andrea|date=2020-02-25|title=The body plan of Halszkaraptor escuilliei (Dinosauria, Theropoda) is not a transitional form along the evolution of dromaeosaurid hypercarnivory|journal=PeerJ|language=en|volume=8|article-number=e8672|doi=10.7717/peerj.8672|issn=2167-8359|pmid=32140312|pmc=7047864 |doi-access=free }}</ref> In 2021, Brum et al. named the clade '''Unenlagiinia''' for a unified ''Unenlagia''+''Halszkaraptor'' clade, recovering them as basal dromaeosaurs.<ref name=Brum2021>{{cite journal|author1=Brum, Arthur S.|author2=Pêgas, Rodrigo V.|author3=Bandeira, Kamila L.N.|author4=Souza, Lucy G.|author5=Campos, Diogenes A.|author6=Kellner, Alexander W.A.|year=2021|title=A new Unenlagiinae (Theropoda: Dromaeosauridae) from the Late Cretaceous of Brazil|journal=Papers in Palaeontology|volume=7|issue=4|pages=2075–2099|doi=10.1002/spp2.1375|s2cid=238854675 }}</ref>

The following cladogram is from Motta et al., 2020, showing Unenlagiidae outside dromaeosaurids and more closely related to Avialae:<ref name=Overoraptor /> {{clade| style=font-size: 100%; line-height:100% |label1=[[Paraves]] |1={{clade |1=[[Troodontidae]] |label2=[[Eumaniraptora]] |2={{clade |1=[[Dromaeosauridae]] |2={{clade |1=[[Microraptoria]] |2={{clade |label1='''Unenlagiidae''' |1={{clade |1=''[[Austroraptor]]'' |2=''[[Buitreraptor]]'' |3=''[[Unenlagia]]'' }} |2={{clade |1={{clade |1=''[[Overoraptor]]'' |2=''[[Rahonavis]]'' }} |label2=[[Avialae]] |2={{clade |label1=[[Archaeopterygidae]] |1={{clade |1=''[[Alcmonavis]]'' |2={{clade |1=''[[Wellnhoferia]]'' |2=''[[Archaeopteryx]]'' }} }} |2={{clade |label1=[[Anchiornithidae]] |1={{clade |1=''[[Xiaotingia]]'' |2=''[[Anchiornis]]'' }} |2={{clade |1=''[[Jeholornis]]'' |2=[[Pygostylia]] }} }} }} }} }} }} }} }} }}

In 2025, Motta et al. recovered Unenlagiidae (along with [[Halszkaraptorinae|Halszkaraptoridae]], [[Anchiornithidae]], and ''[[Archaeopteryx]]'') as within [[Avialae]].<ref name="Motta2025">{{cite journal |last1=Motta |first1=Matías J. |last2=Agnolína |first2=Federico L. |last3=Eglia |first3=Federico Brissón |last4=Rozadillaa |first4=Sebastián |last5=Novas |first5=Fernando E. |title=Phylogenetic relationships of Unenlagiidae among Paraves (Dinosauria) |journal=Journal of Systematic Palaeontology |date=22 Aug 2025 |volume=23 |issue=1 |doi=10.1080/14772019.2025.2529608 |url=https://www.tandfonline.com/doi/full/10.1080/14772019.2025.2529608 |access-date=22 August 2025|url-access=subscription }}</ref> The two trees recovered are reproduced below:

{{columns-start|num=2}} ;Consensus Improved (equal weighting) {{clade| style=font-size: 80%; line-height:75% |label1='''[[Pennaraptora]]''' |1={{clade |1={{clade |1=[[Scansoriopterygidae]] |2=[[Oviraptorosauria]] }} |label2=[[Paraves]] |2={{clade |1=[[Troodontidae]] |label2=[[Eumaniraptora]] |2={{clade |label1=[[Dromaeosauridae]] |1={{clade |1=[[Microraptoria]] |2=[[Eudromaeosauria|Eudromaeosauridae]] }} |label2=[[Avialae]] |2={{clade |label1=Unenlagiinia |1={{clade |1=[[Halszkaraptorinae|Halszkaraptoridae]] |2=[[Unenlagiidae]] }} |2={{clade |1={{clade |1=[[Anchiornithidae]] |2=''[[Archaeopteryx]]'' }} |2={{clade |1=''[[Jeholornis]]'' |2=[[Pygostylia]] }} }} }} }} }} }} }} {{column}} ;Consensus Improved (implied weighting) {{clade| style=font-size: 80%; line-height:75% |label1='''[[Pennaraptora]]''' |1={{clade |1={{clade |1=[[Scansoriopterygidae]] |2=[[Oviraptorosauria]] }} |label2=[[Paraves]] |2={{clade |1=[[Troodontidae]] |label2=[[Eumaniraptora]] |2={{clade |label1=[[Dromaeosauridae]] |1={{clade |1=[[Microraptoria]] |2=[[Eudromaeosauria|Eudromaeosauridae]] }} |label2=[[Avialae]] |2={{clade |label1=Unenlagiinia |1={{clade |1=[[Halszkaraptorinae|Halszkaraptoridae]] |2=[[Unenlagiidae]] }} |2={{clade |1=[[Anchiornithidae]] |2={{clade |1={{clade |1=''[[Fujianvenator]]'' |2=''[[Archaeopteryx]]'' }} |2={{clade |1=''[[Jeholornis]]'' |2=[[Pygostylia]] }} }} }} }} }} }} }} }} {{columns-end}}

==References== {{Reflist}}

[[Category:Unenlagiidae| ]] [[Category:Dinosaur families]] [[Category:Late Cretaceous dinosaurs]]