Platypterygius

{{Automatic taxobox

| name = Platypterygius

| image = Platypterygius australis.jpg

| image_caption = Assigned P. australis specimen

| fossil_range = Late Aptian-Late Cenomanian
{{fossil range|113|93.9}}

| taxon = Platypterygius

| authority = von Huene, 1922

| type_species = {{extinct}}Platypterygius platydactylus

| type_species_authority = (Broili, 1907)

| subdivision_ranks = Other species

| subdivision = * {{extinct}}P. americanus
{{small|(Nace, 1939)}}

{{extinct}}P. australis
{{small|(McCoy, 1867)}}
{{extinct}}P. hercynicus
{{small|Kuhn, 1946}}
{{extinct}}P. elsuntuoso
{{small|Fonseca, Cabra, & Camacho, 2024}}

| synonyms =

Ichthyosaurus platydactylus
{{small|Broili, 1907}}
Longirostria australis
{{small|McCoy, 1867}}
Myobradypterygius mollensis
{{small|Rusconi, 1938}}C. Rusconi. (1938). Restos de ictiosaurios del Jurásico Superior de Mendoza [Remains of ichthyosaurs from the Upper Jurassic of Mendoza]. Boletin Paleontológico de Buenos Aires 10:1-4
Platypterygius longmani
{{small|Wade, 1990}}
Tenuirostria americanus
{{small|Hace, 1939}}

}}

Platypterygius is a historically paraphyletic genus of platypterygiine ichthyosaur from the Cretaceous period. It was historically used as a wastebasket taxon, and most species within Platypterygius likely are undiagnostic at the genus or species level, or represent distinct genera, even being argued as invalid.{{cite journal|author1=Fischer, V.|author2=Masure, E.|author3=Arkhangelsky, M.S.|author4=Godefroit, P.|year=2011|title=A New Barremian (Early Cretaceous) Ichthyosaur From Western Russia|journal=Journal of Vertebrate Paleontology |volume=31|issue=5|pages=1010–1025|doi=10.1080/02724634.2011.595464|bibcode=2011JVPal..31.1010F |hdl=2268/92828 |s2cid=86036325 |hdl-access=free}} While fossils referred to Platypterygius have been found throughout different continents, the holotype specimen was found in Germany.

Description

File:Platypterigius longmani DB.jpg

As Platypterygius contains multiple species not especially close to each other, little can be said in terms of shared characteristics. According to an analysis by Fischer (2012), all anatomical features used to unify Platypterygius species are either not actually present in each species, or much more widespread among unrelated ophthalmosaurs. Generally, species referred to this genus were large bodied macropredators based on their robust dentition.{{Cite journal|last1=Fischer|first1=V.|last2=Bardet|first2=N.|last3=Benson|first3=R.B.J.|last4=Arkhangelsky|first4=M.S.|last5=Friedman|first5=M.|date=2016|title=Extinction of Fish-shaped Marine Reptiles Associated with Reduced Evolutionary Rates and Global Environmental Volatility|journal=Nature Communications|volume=7|page=10825|doi=10.1038/ncomms10825|pmid=26953824|pmc=4786747|bibcode=2016NatCo...710825F}} This is also supported by P. australis having been found with remains of hatchling protostegid sea turtles and enantiornithines (possibly Nanantius) in association with actinopterygian fish in its guts.{{cite journal |last1=Kear |first1=Benjamin P. |last2=Boles |first2=Walter E. |last3=Smith |first3=Elizabeth T. |year=2003 |title=Unusual gut contents in a Cretaceous ichthyosaur |journal=Proceedings of the Royal Society B |volume=270 |issue= Suppl 2|pages=S206–S208 |doi = 10.1098/rsbl.2003.0050 |pmid=14667384 |pmc=1809966}}

In 1998, Arkhangelsky estimated that P. platydactylus was about {{convert|5|m|ft}} long, while "P." americanus was about {{convert|5.5|m|ft}} long. In 2010, Zammit and colleagues estimated that "P." australis was about {{convert|7|m|ft}} long.{{cite journal|author=Maria Zammit, Rachel M. Norris & Benjamin P. Kear|year=2010|title=The Australian Cretaceous ichthyosaur Platypterygius australis: a description and review of postcranial remains|journal=Journal of Vertebrate Paleontology|volume=30|issue=6|pages=1726–1735|doi=10.1080/02724634.2010.521930|bibcode=2010JVPal..30.1726Z |s2cid=85089080 }}

Discovery and species

File:Platypterygius sp. (fossil Ichthyosaur).jpg]]

The type species of Platypterygius was described in 1922 based on remains found in upper Aptian strata around Hannover, Germany that were previously described as a species of Ichthyosaurus (I. platydactylus) in 1907 by Ferdinand Broili. These remains however were not adequately described and to complicate matters further, destroyed during World War 2. In the time after its discovery however Platypterygius has become a catch-all genus for Cretaceous ichthyosaurs, creating the misconstrued view of post-Jurassic ichthyosaurs as being a single global genus lacking in diversity. Later research conducted in the 2000s and 2010s has repeatedly shown this to be false, with all of the autapomorphies previously used to define Platypterygius either not being present in all assigned species or also being present in other ophthalmosaurids.{{cite journal |first1=V. |last1=Fischer |year=2012 |title=New Data on the Ichthyosaur Platypterygius hercynicus and Its Implications for the Validity of the Genus |journal=Acta Palaeontologica Polonica |volume=57 |issue=1 |pages=123–134|doi=10.4202/app.2011.0007 |s2cid=53355007 |doi-access=free }} As the holotype was destroyed, a redescription of the material attempting to identify valid autapomorphies is out of the question and leaves the genus in a problematic state. Furthermore, the inclusion of later described genera of Cretaceous, platypterygiine ichthyosaurs has shown Platypterygius to be paraphyletic, with the different species not clading closely to one another. Subsequently, many redescriptions of referred Platypterygius species have found them to be their own distinct genera.

One notable attempt at revising Platypterygius was conducted by Arkhangel'sky in 1998, who split the genus into three new subgenera. Longirostria (including the Australian "P." longmani, a synonym of "P." australis, and the Argentinian "P." hauthali), Tenuirostria ("P." americanus) and Pervushovisaurus (which included the newly described "P." bannovkensis). Both Platypterygius platydactylus,"P." kiprianoffi and "P." hercynicus were placed in the subgenus Platypterygius.{{cite journal |first1=M.S. |last1=Arkhangelsky |year=1998 |title=On the Ichthyosaurian genus Platypterygius |journal=Paleontological Journal |volume=32 |issue=6 |pages=611–615}}

"Platypterygius" bannovkensis was eventually elevated to its own genus Pervushovisaurus in 2014, utilizing Arkhangel'sky's proposed subgenus name{{cite journal | last1 = Fischer | first1 = Valentin | last2 = Arkhangelsky | first2 = Maxim S. | last3 = Naish | first3 = Darren | last4 = Stenshin | first4 = Ilya M. | last5 = Uspensky | first5 = Gleb N. | last6 = Godefroit | first6 = Pascal | year = 2014 | title = Simbirskiasaurus and Pervushovisaurus reassessed: implications for the taxonomy and cranial osteology of Cretaceous platypterygiine ichthyosaurs | journal = Zoological Journal of the Linnean Society | volume = 171 | issue = 4| pages = 822–841 | doi=10.1111/zoj.12158| doi-access = free }} and "P." campylodon was also assigned to this genus by a study published in 2016.{{cite journal |first1=V. |last1=Fischer |date=2016 |title=Taxonomy of Platypterygius campylodon and the diversity of the last ichthyosaurs |journal=PeerJ |volume=4 |page=e2604 |doi=10.7717/peerj.2604 |pmid=27781178 |pmc=5075704 |doi-access=free }} "P." kiprianoffi was also assigned to P. campylodon (now Pervushovisaurus).{{cite book|year=2000|pages=187–210|publisher=Cambridge University Press|location=Cambridge, UK|chapter=Mesozoic marine reptiles of Russia and other former Soviet Republics|title=The Age of Dinosaurs in Russia and Mongolia}}{{cite journal|author1=McGowan, C.|author2= Motani, R.|title=Ichthyopterygia|journal=Handbook of Paleoherpetology|location=Munich, Germany|year=2003|volume=8|pages=175}}{{cite journal|last=Zammit|first=M.|year=2012|title=Cretaceous Ichthyosaurs: Dwindling Diversity, or the Empire Strikes Back?|journal=Geosciences|volume=2|issue=2|pages=187–210|doi=10.3390/geosciences2020011|bibcode=2012Geosc...2...11Z |doi-access=free}} Simbirskiasaurus was originally described in 1985 and later sunk into Platypterygius before being declared distinct in the same paper as Pervushovisaurus. "Platypterygius" ochevi, described in 2008 by Arkhangel'sky et al., was found to be a junior synonym of Maiaspondylus cantabrigiensis{{cite journal |author1=Nikolay G. Zverkov |author2=Dmitry V. Grigoriev |year=2020 |title=An unrevealed lineage of platypterygiines (Ichthyosauria) with peculiar forefin structure and semiglobal distribution in the mid-Cretaceous (Albian–Cenomanian) |journal=Cretaceous Research |volume=115 |pages=Article 104550 |doi=10.1016/j.cretres.2020.104550 |bibcode=2020CrRes.11504550Z |s2cid=225721312 }} and in 2021 "Platypterygius" sachicarum was described by Cortés et al. as Kyhytysuka sachicarum.{{cite journal |last1=Cortés |first1=D. |last2=Maxwell |first2=E.E. |last3=Larsson |first3=H.C.E. |year=2021 |title=Re-appearance of hypercarnivore ichthyosaurs in the Cretaceous with differentiated dentition revision of Platypterygius sachicarum (Reptilia:Ichthyosauria, Ophthalmosauridae) from Colombia |journal=Journal of Systematic Palaeontology|volume=19 |issue=14 |pages=969–1002 |doi= 10.1080/14772019.2021.1989507|bibcode=2021JSPal..19..969C |s2cid=244512087 }} It is argued that the inclusion of oldest species "P." hauthali requires reinvestigation, for it lacks a skull to attribute.{{cite journal|author1=Maxwell, E.E.|author2=Kear, B.P.|year=2010|title=Postcranial anatomy of Platypterygius americanus (Reptilia: Ichthyosauria) from the Cretaceous of Wyoming|journal=Journal of Vertebrate Paleontology |volume=30|issue=4|pages=1059–1068|doi=10.1080/02724634.2010.483546|bibcode=2010JVPal..30.1059M |s2cid=85817541 }} Because of this, recent analyses on ichthyosaur classification neglect this species.{{cite journal |author1=Nikolay G. Zverkov |author2=Vladimir M. Efimov |name-list-style=amp |year=2019 |title=Revision of Undorosaurus, a mysterious Late Jurassic ichthyosaur of the Boreal Realm |journal=Journal of Systematic Palaeontology |volume=17 |issue=14 |pages=963–993 |doi=10.1080/14772019.2018.1515793 |bibcode=2019JSPal..17.1183Z |s2cid=91912834 |url=https://figshare.com/articles/Revision_of_i_Undorosaurus_i_a_mysterious_Late_Jurassic_ichthyosaur_of_the_Boreal_Realm/7624868 }} In 2024, "P." hauthali was reclassified back into the original genus, Myobradypterygius.{{Cite journal |last1=Campos |first1=L. |last2=Fernández |first2=M. S. |last3=Bosio |first3=V. |last4=Herrera |first4=Y. |last5=Manzo |first5=A. |year=2024 |title=Revalidation of Myobradypterygius hauthali Huene, 1927 and the phylogenetic signal within the ophthalmosaurid (Ichthyosauria) forefins |journal=Cretaceous Research |volume=157 |at=105818 |doi=10.1016/j.cretres.2023.105818|bibcode=2024CrRes.15705818C }}

= Accepted species =

File:Opalised Ichthyosaur backbone.jpg vertebral column assigned to an immature P. cf. longmani (a synonym of P. australis)]]

Platypterygius platydactylus {{small|Broilli, 1907 (type)}}
Platypterygius americanus {{small|Nace, 1939}} (=Tenuirostria)
Platypterygius australis {{small|McCoy, 1867}} (=Longirostria)
Platypterygius hercynicus {{small|Kuhn, 1946}}

= Formerly assigned species =

Pervushovisaurus bannovkensis {{small|Arkhangelsky, 1998}}{{cite journal |first1=Valentin |last1=Fischer |first2=Maxim S. |last2=Arkhangelsky |first3=Darren |last3=Naish |first4=Ilya M. |last4=Stenshin |first5=Gleb N. |last5=Uspensky |first6=Pascal |last6=Godefroit |date=2014 |title=Simbirskiasaurus and Pervushovisaurus reassessed: implications for the taxonomy and cranial osteology of Cretaceous platypterygiine ichthyosaurs |journal=Zoological Journal of the Linnean Society |volume=171 |issue=4 |pages=822–841 |doi=10.1111/zoj.12158 |doi-access=free }}
Pervushovisaurus campylodon {{small|Carter, 1846}}{{cite journal |first1=V. |last1=Fischer |date=2016 |title=Taxonomy of Platypterygius campylodon and the diversity of the last ichthyosaurs |journal=PeerJ |volume=4 |page=e2604 |doi=10.7717/peerj.2604 |pmid=27781178 |pmc=5075704 |doi-access=free }}
Simbirskiasaurus birjukovi {{small|Otschev and Efimov, 1985}}
Plutoniosaurus bedengensis {{small|Efimov, 1997}}
Maiaspondylus cantabrigiensis (senior synonym of Platypterygius ochevi {{small|Arkhangelsky et al., 2008}})
Kyhytysuka sachicarum {{small|Cortés et al., 2021}} (formerly Platypterygius sachicarum {{small|Páramo, 1997{{cite journal |last1=Páramo |first1=M.E. |year=1997 |title=Platypterygius sachicarum (Reptilia, Ichthyosauria) nueva especie del Cretácico de Colombia |journal=Revista INGEOMINAS |volume=6 |pages=1–12|author1-link=María Páramo }}}})
Myobradypterygius hauthali {{Small|von Huene, 1927}}

Classification

File:Ichthyosaur Skeleton, Platypterygius longmani, in The Museum and Art Gallery of the Northern Territory at Darwin.jpg]]

The following cladogram shows the internal relationships of ophthalmosaurian ichthyosaurs according to an analysis performed by Zverkov and Jacobs (2020) which shows that P. americanus is too distantly related compared to the other three species.{{cite journal |author1=Nikolay G. Zverkov |author2=Megan L. Jacobs |year=2020 |title=Revision of Nannopterygius (Ichthyosauria: Ophthalmosauridae): reappraisal of the 'inaccessible' holotype resolves a taxonomic tangle and reveals an obscure ophthalmosaurid lineage with a wide distribution |journal=Zoological Journal of the Linnean Society |volume=191 |pages=228–275 |doi=10.1093/zoolinnean/zlaa028}}

{{clade

|label1=Ophthalmosauria

|1={{clade

|label1=Ophthalmosaurinae

|1={{clade

|1=Acamptonectes densus

|2={{clade

|1=Mollesaurus periallus

|2={{clade

|1=Ophthalmosaurus natans

|2=Ophthalmosaurus icenicus

}}

}} }} }}

|2={{clade

|1={{clade

|1=Gengasaurus nicosiai

|2={{clade

|1={{clade

|1=Nannopterygius yasykovi

|2={{clade

|1=Nannopterygius enthekiodon

|2=Nannopterygius saveljeviensis

|3=Nannopterygius borealis

}}

|2={{clade

|1={{clade

|1=Arthropterygius volgensis

|2={{clade

|1=Arthropterygius lundi

|2=Arthropterygius thalassonotus

|3={{clade

|1=Arthropterygius hoybergeti

|2=Arthropterygius chrisorum

}}

|label2=Platypterygiinae

|2={{clade

|1={{clade

|1=Brachypterygius extremus

|2=Aegirosaurus leptospondylus

|3={{clade

|1=Muiscasaurus catheti

|2={{clade

|1=Leninia stellans

|2={{clade

|1=Sveltonectes insolitus

|2={{clade

|1=Athabascasaurus bitumineus

|2={{clade

|1=Platypterygius americanus

|2={{clade

|1={{clade

|1=Acuetzpalin carranzai

|2=Platypterygius sachicarum

|3=Caypullisaurus bonapartei

}}

|2={{clade

|1={{clade

|1=Grendelius mordax

|2=Grendelius alekseevi

|3=Grendelius pseudoscythicus

|4=Grendelius zhuravlevi

}}

|2={{clade

|1={{clade

|1=Undorosaurus kielanae

|2={{clade

|1=Undorosaurus nessovi

|2=Undorosaurus gorodischensis

}}

|3={{clade

|1=Platypterygius australis

|2={{clade

|1=Plutoniosaurus bedengensis

|2=Simbirskiasaurus birjukovi

|3=Platypterygius hercynicus

|4=Sisteronia seeleyi

|5=Platypterygius platydactylus

|6=Maiaspondylus lindoei

}}

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

References

= Bibliography =

{{cite journal |last1=Arkhangelsky |first1=M.S. |last2=Averianov |first2=A.O. |last3=Pervushov |first3=E.M. |last4=Ratnikov |first4=V. Yu |last5=Zozyrev |first5=N. Yu. |year=2008 |title=On ichthyosaur remains from the Cretaceous of the Voronezh region |journal=Paleontological Journal |volume=42 |issue=3 |pages=287–291|doi=10.1134/S0031030108030106 |bibcode=2008PalJ...42..287A |s2cid=128822178 }}
{{cite journal |first1=Patrick S. |last1=Druckenmiller |first2=Erin E. |last2=Maxwell |year=2010 |title=A new Lower Cretaceous (lower Albian) ichthyosaur genus from the Clearwater Formation, Alberta, Canada |journal=Canadian Journal of Earth Sciences |volume=47 |issue=8 |pages=1037–1053 |doi=10.1139/E10-028 |url=http://rparticle.web-p.cisti.nrc.ca/rparticle/AbstractTemplateServlet?calyLang=eng&journal=cjes&volume=47&year=0&issue=8&msno=e10-028 |bibcode=2010CaJES..47.1037D |url-access=subscription }}{{dead link|date=March 2018 |bot=InternetArchiveBot |fix-attempted=yes}}
{{cite journal |last1=Fernández |first1=M. |year=2007 |title=Redescription and phylogenetic position of Caypullisaurus (Ichthyosauria: Ophthalmosauridae) |journal=Journal of Paleontology |volume=81 |issue=2 |pages=368–375 |doi=10.1666/0022-3360(2007)81[368:rappoc]2.0.co;2|s2cid=130457040 }}
{{cite journal |last1=Pardo Pérez |first1=Judith |last2=Frey |first2=Eberhard |last3=Stinnesbeck |first3=Wolfgang |last4=Fernández |first4=Marta S. |last5=Rivas |first5=Luis |last6=Salazar |first6=Christian |last7=Leppe |first7=Marcelo |date=2012 |title=An ichthyosaurian forefin from the Lower Cretaceous Zapata Formation of southern Chile: implications for morphological variability within Platypterygius |url=https://www.researchgate.net/publication/230727454 |journal= Palaeobiodiversity and Palaeoenvironments|volume=92 |issue= 2|pages=287–294 |doi=10.1007/s12549-012-0074-8 |bibcode=2012PdPe...92..287P |s2cid=128487253 |access-date=30 August 2016}}