Navaornis

{{Speciesbox

| fossil_range = Late Cretaceous (late Santonian–early Campanian), {{fossilrange|85|75}}

| image = Navaornis hestiae holotype.png

| image_caption = Fossil material of Navaornis (white and light grey in "b") and an unnamed specimen (dark grey)

| display_parents = 2

| genus = Navaornis

| parent_authority = Chiappe et al., 2024

| species = hestiae

| authority = Chiappe et al., 2024

}}

Navaornis is an extinct genus of enantiornithean birds from the Late Cretaceous Adamantina Formation of Brazil. The genus contains a single species, N. hestiae, known from a well preserved skull and skeleton.{{Cite journal |last1=Chiappe |first1=Luis M. |last2=Navalón |first2=Guillermo |last3=Martinelli |first3=Agustín G. |last4=Carvalho |first4=Ismar de Souza |last5=Miloni Santucci |first5=Rodrigo |last6=Wu |first6=Yun-Hsin |last7=Field |first7=Daniel J. |date=2024-10-30 |title=Cretaceous bird from Brazil informs the evolution of the avian skull and brain |journal=Nature |language=en |volume=635 |issue=8038 |pages=376–381 |doi=10.1038/s41586-024-08114-4 |pmid=39537887 |issn=1476-4687|pmc=11560842 |bibcode=2024Natur.635..376C }}

Discovery and naming

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|image1=Navaornis hestiae holotype skull.png

|caption1=Preserved holotype skull and diagram

|image2=Navaornis skull.webp

|caption2=Three-dimensional cranial reconstruction of Navaornis

}}

The Navaornis fossil material was discovered in 2016 in sediments of the Adamantina Formation ('William's Quarry' bonebed, Bauru Group) in São Paulo State, southeastern Brazil. The holotype specimen comprises a complete skull with an associated postcranial skeleton. A single basicranium described in 2022 was also referred to Navaornis based on its similarities with the holotype.{{Cite journal |last1=Chiappe |first1=Luis M. |last2=Navalón |first2=Guillermo |last3=Martinelli |first3=Agustín G. |last4=Nava |first4=William |last5=Field |first5=Daniel J. |date=2022-09-28 |title=Fossil basicranium clarifies the origin of the avian central nervous system and inner ear |journal=Proceedings of the Royal Society B: Biological Sciences |language=en |volume=289 |issue=1983 |doi=10.1098/rspb.2022.1398 |issn=0962-8452 |pmc=9515635 |pmid=36168759}}

In 2024, Chiappe et al. described Navaornis hestiae as a new genus and species of enantiornithean birds based on these fossil remains. The generic name, Navaornis, combines "Nava"—honoring William Nava, the discoverer of the holotype and type locality—with the Greek word "ornis", meaning "bird". The specific name, hestiae, references the Greek goddess Hestia, who is considered to be both the oldest and youngest Olympian—similar to the archaic phylogenetic position of Navaornis combined with its modern skull morphology.

Classification

File:Navaornis_UDL.png]]

In their phylogenetic analyses, Chiappe et al. (2024) recovered Navaornis as a derived member of the extinct Cretaceous bird clade Enantiornithes, clustering with Yuornis and Gobipteryx, two other edentulous birds with beaks. However, they noted that due to the low support for specific enantiornithean relationships, this grouping may not represent a legitimate toothless clade. Their results are displayed in the cladogram below:

{{clade

|{{clade

|1=Protopteryx

|2={{clade

|1=Orienantius

|2={{clade

|1={{clade

|1=Eopengornis

|2=Parapengornis }}

|3={{clade

|1=Shenqiornis

|2={{clade

|1={{clade

|1=Junornis

|2=Gretcheniao }}

|3={{clade

|1=Sulcavis

|2={{clade

|1=Zhouornis

|2={{clade

|1=Longusunguis

|2={{clade

|1=Bohaiornis

|2={{clade

|1=Qiliania

|2=Parabohaiornis }} }} }} }} }} }}

|3={{clade

|1={{clade

|1=Vescornis

|2={{clade

|1=Neuquenornis

|2=Pengornis }} }}

|3={{clade

|1=Eoenantiornis

|2={{clade

|1=CUGB P1202
{{small|(indeterminate unnamed enantiornithean){{Cite journal |last1=Peteya |first1=Jennifer A. |last2=Clarke |first2=Julia A. |last3=Li |first3=Quanguo |last4=Gao |first4=Ke-Qin |last5=Shawkey |first5=Matthew D. |date=2017 |editor-last=Gabbott |editor-first=Sarah |title=The plumage and colouration of an enantiornithine bird from the Early Cretaceous of China |journal=Palaeontology |language=en |volume=60 |issue=1 |pages=55–71 |doi=10.1111/pala.12270 |bibcode=2017Palgy..60...55P |s2cid=89530170 |issn=0031-0239|doi-access=free }}}}

|2={{clade

|1={{clade

|1=Concornis

|2={{clade

|1=Elsornis

|2=Longipteryx }} }}

|3={{clade

|1=Shanweiniao

|2={{clade

|1=Longirostravis

|2=Rapaxavis }} }} }}

|3={{clade