Talk:Undorosaurus

Merge Cryopterygius?

Undorosaurus & Cryopterygius have long been recognized as similar, and in 2019, Zverkov & Efimov synonymized Cryopterygius with Undorosaurus and C. kristiansenae with U. gorodischensis (C. kielane became U. kielane. [1] Later that same year, Delsett et al. reviewed their decision, and while they found some errors, they did not consider the two genera to be different enough to keep separate, although they rejected the synonymy of C. kristiansenae and U. gorodischensis, referring the former as U.? kristiansenae. [2] This seems rather significant, as they could have maintained Cryopterygius as separate based on phylogeny, and considered the contentious genera Keilhauia, Janusaurus, and Palvennia to be valid as well. Another 2019 publication by Campos et al. [3] failed to recover a monophyletic Undorosaurus, but instead of splitting Cryopterygius back out, they put quotation marks around its name, though there is a frustrating lack of discussion about this. The latest major revision of ophthalmosaurs that I know of is the Nannopterygius redescription, though I don't know if the Cryopterygius situation is given any discussion there as the paper is not OA (though perhaps it will be by January?). However, it seems that the general consensus is that Cryopterygius is invalid, and Undorosaurus seems to be the genus to sink it into, which is why I've proposed this merge. --Slate Weasel [Talk - Contribs] 17:32, 27 December 2021 (UTC)

• As explained here ([4]), I no longer support this merger. I seem to have misinterpreted the literature, and the case that Cryopterygius is distinct seems to have more support than its synonymy. --Slate Weasel [Talk - Contribs] 14:45, 14 March 2022 (UTC)

Cryopterygius Round Two

I previously proposed merging Cryopterygius into Undorosaurus, but later retracted my proposal after an argument by Huinculsaurus proposed on my talk page: [5]. However, having reconsidered, I feel that I must propose this merge again. To summarize what happened in the literature, starting at the synonymy of the two genera:

• Zverkov & Efimov (2019) formally synonymized the two genera. Additionally, they synonymized their type species as well, subsuming C. kristiansenae into U. gorodischensis. C. kielane was retained as a separate species, U. kielanae.
• Delsett et al. (2019) reviewed the synonymy, and found various issues with the synonymy of C. kristiansenae with U. gorodischensis. Their phylogenetic analyses did not recover monophyletic Undorosaurus. However, they noted that the two were still quite similar, and refered to the Cryopterygius holotype as U.? kristiansenae, noting more work would be needed.
• Campos et al. (2019) mentioned the synonymy of C. kristiansenae with U. gorodischensis, but had them coded separately in their analysis "to avoid ad hoc assumptions". They did not find the two taxa to clade together, but did not comment on whether they considered the genera distinct or synonymous (though, for what it is worth, they did consistently write "Cryopterygius" using quotes).
• Various other studies on ophthalmosaurs have mentioned Cryopterygius/Undorosaurus, some following the synonymy (i.e., Massare et al. (2021)), some treating them as separate genera (i.e., Cortés et al. (2021)), and some remaining neutral (i.e., Weryński & Błażejowski (2023)).

Overall, starting at the synonymy, there were three papers that directly mentioned the Cryopterygius/Undorosaurus synonymy, all treated Cryopterygius as invalid (two explictly, one implicitly), and the two that explicitly considered it invalid synonymized it with Undorosaurus. Therefore, I think it is reasonable to merge these two articles. --Slate Weasel [Talk - Contribs] 22:47, 27 December 2023 (UTC)

• Support It's best if these taxa are covered in the same article for conciseness. Hemiauchenia (talk) 22:57, 27 December 2023 (UTC)
• Comment: In their recent description of the new genus Argovisaurus, Miedema et al. (2024) mention the synonymy as well (Cryopterygius (= Undorosaurus)? kristiansenae). -SlvrHwk (talk) 01:47, 19 March 2024 (UTC)

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Comment: If merge to be performed, two more sites must be handled: commons:Category:Cryopterygius and wikidata.- (in wikidata the "Wikipedia" record must be edited and the type of en:Cryopterygius must be changed to "sitelink to redirect") Altenmann >talk 23:10, 27 December 2023 (UTC)

  Y Merger complete. Klbrain (talk) 13:14, 20 July 2024 (UTC)

Wikidata adjusted as suggested. Klbrain (talk) 13:17, 20 July 2024 (UTC)