Eotetrapodiformes

This clade is defined as "the node-based clade arising from the most recent common ancestor of Eusthenopteron and Ichthyostega plus all of its descendants," for their litany of shared morphological characteristics, such as similarities in their lower jaws and endocrania. Utilizing the holotype FMNH PF 610 of the sarcopterygian Litoptychus bryanti, paleontologists highlighted the division between the ethmoid and sphenoid processes, as well as vomeral and parasphenoid processes similar to those of more derived tetrapods. Eotetrapodiformes are considered a sister taxon to Megalichthyiformes and Rhizodontida.

The clade was named in 2010 by Michael I. Coates and Matt Friedman.

The majority of eotetrapodimorphs have been discovered from formations from southern Euramerica. The earliest tetrapodomorphs are known from China and Australia, from a time where relatively few examples have been discovered outside of East Asia and eastern Gondwana.

Families described in this clade evolved in the lower Devonian period 400 to 5 million years ago. And evolved into other different species. Most of the geological stages that have the highest recorded number of formations are restricted to southern Euramerica where the majority of eotetrapodiform taxa have been discovered.{{cite journal |last1=Gardener |first1=Jacob D |last2=Surya |first2=Kevin |last3=Organ |first3=Chris L |date=2019 |title=Early tetrapodomorph biogeography: Controlling for fossil record bias in macroevolutionary analyses |journal=Comptes Rendus Palevol |volume=18 |pages=699–709}} In Coates and Friedman's seminal paper defining eotetrapodiformes as separate from megalichthyiformes and rhizodontids, they hypothesized that though each clade diversified considerable throughout the Devonian, only the limbed tetrapods survived beyond.{{Cite book |url=https://www.worldcat.org/oclc/682880899 |title=Morphology, phylogeny and paleobiogeography of fossil fishes : honoring Meemann Chang |date=2010 |publisher=F. Pfeil |others=Miman Zhang, David K. Elliott |isbn=978-3-89937-122-2 |location=München |oclc=682880899}}

Cladogram from Swartz, 2012:

{{clade| style=font-size:85%;line-height:85%

|1={{clade

|1=Megalichthyiformes 70 px

|label2=Eotetrapodiformes

|2={{clade

|1=Tristichopteridae 70px

|2={{clade

|1=Tinirau

|2={{clade

|1=Platycephalichthys 70 px

|label2=Elpistostegalia

|2={{clade

|1=Panderichthys 70 px

|2={{clade

|1={{clade

|1=Tiktaalik 70 px

|2=Elpistostege}}

|2={{clade

|1=Elginerpeton 70 px

|2={{clade

|1=Ventastega 60 px

|2={{clade

|1=Acanthostega 70 px

|2={{clade

|1=Ichthyostega 70 px

|2={{clade

|1=Whatcheeriidae 70 px

|2={{clade

|1=Colosteidae 70 px

|2={{clade

|1=Crassigyrinus 70 px

|2={{clade

|1=Baphetidae 70 px

|2=Tetrapoda (Crown group) 70 px

}} }} }} }} }} }} }} }} }} }} }} }} }} }} }}

{{Reflist|refs=

{{cite journal |last1=Clement |first1=A. M. |last2=Cloutier |first2=R. |last3=Lu |first3=J. |last4=Perilli |first4=E. |last5=Maksimenko |first5=A. |last6=Long |first6=J. |title=A fresh look at Cladarosymblema narrienense, a tetrapodomorph fish (Sarcopterygii: Megalichthyidae) from the Carboniferous of Australia, illuminated via X-ray tomography |journal=PeerJ |date=2021 |volume=9 |pages=e12597 |doi=10.7717/peerj.12597|doi-access=free |pmc=8667741 }}

{{cite book |last=Coates |first=M. I. |last2=Friedman |first2=M. |year=2010 |chapter=Litoptychus bryanti and characteristics of stem tetrapod neurocrania |title=Morphology, Phylogeny and Paleobiogeography of Fossil Fishes |editor=Elliot, D.K. |editor2=Maisey, J.G. |editor3=Yu, X. |editor4=Miao, D. |publisher=Pfeil |isbn=978-3-89937-122-2 |pages=389–416}}

{{cite journal | last = Swartz | first = B. | year = 2012 | title = A marine stem-tetrapod from the Devonian of Western North America | journal = PLOS ONE | pmid = 22448265 | volume = 7 | issue = 3 | pmc = 3308997 | pages = e33683 | doi = 10.1371/journal.pone.0033683 | bibcode = 2012PLoSO...733683S | doi-access = free }}

}}

{{Tetrapodomorpha|Eo.}}

{{Taxonbar|from=Q5381965}}

Category:Extant Devonian first appearances

Category:Evolution of tetrapods