Vieraella (Early Jurassic frog) redescribed + Foxemys (Late Cretaceous turtle) skull morphology + tinamou phylogeny and classification + rafting iguanas

[Ben Creisler]

Ben Creisler

bcre...@gmail.com

Some recent non-dino papers:

Ana M. Báez & Laura Nicoli (2025)
Re-examination of the oldest known frog from South America: New data prompt new evolutionary interpretations
The Anatomical Record (advance online publication)
doi: https://doi.org/10.1002/ar.25654
https://anatomypubs.onlinelibrary.wiley.com/doi/10.1002/ar.25654


Available paleontological evidence, although scarce, points to the early diversification of salientian lissamphibians in the Triassic and Early Jurassic. This study provides new key anatomical information on the earliest mostly articulated frog currently known, thereby improving our understanding of the early evolution of this lissamphibian lineage. Herein, available specimens of the Early Jurassic Vieraella herbstii from Patagonia, which consist of dorsal and ventral imprints of the incomplete, partially articulated skeleton of a single individual, are thoroughly redescribed. Although we comment on its known features, we focus on those that had been misinterpreted or overlooked previously. Among other features, we address the relative proportions of the skull regions and limbs, the morphology of the vomers, the peculiar articulation of the palatine flanges of premaxilla and maxilla that suggests the presence of well-developed cristae subnasales, and the presence of prepollex. The most surprising, significant findings are the presence of stapes, indicating the possibility of a complete tympanic middle ear, and of a short, tapering urostyle and postsacral vertebral elements. Based on available information, we present partial reconstructions of the pectoral girdle and the skeleton of Vieraella in the dorsal aspect. Discussion of the evolutionary significance of these features and perusal of the phylogenetic and functional analyses that included Vieraella in the taxon sampling highlight the necessity of thorough revision of the scorings and measurements, incorporating information presented herein. This reassessment will be relevant not only to clarify its relationships but also to provide sound insights into the early diversification of frogs.

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Haiyan Tong, Eric Buffetaut & Julien Claude (2025)
Skull morphology of Foxemys (Testudines: Pleurodira: Bothremydidae) from the Upper Cretaceous of Massecaps, Cruzy, southern France
Historical Biology (advance online publication)
doi: https://doi.org/10.1080/08912963.2025.2478209
https://www.tandfonline.com/doi/full/10.1080/08912963.2025.2478209


The Massecaps locality (Cruzy, Department of Hérault, France) has yielded abundant turtle remains. Most of them have been referred to Foxemys mechinorum Tong, Gaffney and Buffetaut, 1998 which belongs to Bothremydidae, an extinct pleurodiran turtle family. A previous study has shown that skulls from that locality exhibited some differences from the type series. It was suggested that these differences may represent intraspecific variation or diagnostic characters for a separate taxon. In this paper, the skulls from the Massecaps locality are described. Comparisons with the type series of Foxemys mechinorum confirm the assignment of the Massecaps bothremydids to that species. The cranial differences from the type series are interpreted as intraspecific variation and may be explained mainly by ontogeny.

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Sara Bertelli, Francisca Cunha Almeida & Norberto P. Giannini (2025)
A new phylogeny and classification of the tinamous, volant palaeognathous birds from the Neotropics
Cladistics (advance online publication)
doi: https://doi.org/10.1111/cla.12605
https://onlinelibrary.wiley.com/doi/10.1111/cla.12605


The Neotropical Tinamidae is the most diverse family of palaeognathous birds (Neornithes; Palaeognathae). This is the only family with species capable of powered flight, in striking contrast to all the other flightless, large-bodied, both living and recently extinct, palaeognaths. Here we report our latest phylogenetic analysis of tinamous, built on previous comprehensive studies, presently including all 46 currently recognized species. Our goal was to apply all the valid available supraspecific names to the clades recovered, creating new ones as needed. We recovered the traditional major subclades, forest-dwelling vs. open-areas tinamous, with all three currently recognized genera in the former matching the chief groupings, and with two taxa in the latter that do not fit the current classification as per the phylogenetic results. Our analysis of the taxonomic history of tinamid taxa revealed complications chiefly owing to the convoluted history of certain key names, particularly Tinamus. We disentangled the perceived misapplication of Tinamus to various tinamid taxa, concluding that Tinamus Hermann, 1783 is valid and not Tinamus Latham, 1790, with type species soui Hermann, 1783, currently placed in Crypturellus. As a consequence, while the phylogenetic signal is clear, a major taxonomic rearrangement is needed in the forest-dwelling tinamous reassigning species of small forest tinamous (currently in Crypturellus) according to priority to Tinamus Hermann, and former invalid Tinamus Latham to Pezus Spix, 1825. In the open-areas tinamous (Tinamotidinae), we recognize two tribes and the phylogeny also indicated the need for a new genus to be applied to cinerascens, formerly in Nothoprocta; and the synonymy of Taoniscus, as the single species nanus was recovered nested in Nothura. We discuss at length our taxonomic proposal against alternatives; this is particularly complicated owing to a long, unresolved taxonomic history.

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Simon G Scarpetta, Robert N Fisher, Benjamin R Karin, Jone B Niukula, Ammon Corl, Todd R Jackman & Jimmy A McGuire (2025)
Iguanas rafted more than 8,000 km from North America to Fiji.
Proceedings of the National Academy of Sciences 122(12): e2318622122
doi: https://doi.org/10.1073/pnas.2318622122
https://www.pnas.org/doi/10.1073/pnas.2318622122


Significance

Transoceanic dispersal to far-away islands is an important mechanism for the generation of new species lineages and biotas and has captivated scientists since at least the time of Darwin. Determining whether and how such events occur is challenging, particularly for hypothesized dispersals spanning thousands of kilometers. We addressed the enigmatic occurrence of Fijian iguanas via phylogenomic and biogeographic analyses, providing strong evidence that iguanas rafted >8,000 km from North America as early as the Paleogene. This represents the longest documented transoceanic dispersal in terrestrial vertebrates. Our findings elaborate on the importance of long-distance dispersal in the diversification of iguanids. Iguanid lizards display a propensity for overwater dispersal, which could stimulate further research into the predictability of these incredible biogeographic events.


Abstract

Founder-event speciation can occur when one or more organisms colonize a distant, unoccupied area via long-distance dispersal, leading to the evolution of a new species lineage. Species radiations established by long-distance, and especially transoceanic, dispersal can cause substantial shifts in regional biodiversity. Here, we investigate the occurrence and timing of the greatest known long-distance oceanic dispersal event in the history of terrestrial vertebrates—the rafting of iguanas from North America to Fiji. Iguanas are large-bodied herbivores that are well-known overwater dispersers, including species that colonized the Caribbean and the Galápagos islands. However, the origin of Fijian iguanas had not been comprehensively tested. We estimated the phylogenetic relationships and evolutionary timescale of the iguanid lizard radiation using genome-wide exons and ultraconserved elements (UCEs). Those data indicate that the closest living relative of extant Fijian iguanas is the North American desert iguana and that the two taxa likely diverged during the late Paleogene near or after the onset of volcanism that produced the Fijian archipelago. Biogeographic models estimate North America as the most probable ancestral range of Fijian iguanas. Our analyses support the hypothesis that iguanas reached Fiji via an extraordinary oceanic dispersal event from western North America, and which spanned a fifth of the earth’s circumference (>8,000 km). Overwater rafting of iguanas from North America to Fiji strengthens the importance of founder-event speciation in the diversification of iguanids and elucidates the scope of long-distance dispersal across terrestrial vertebrates.

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News:

Iguanas floated one-fifth of the way around the world to colonize Fiji

https://news.berkeley.edu/2025/03/17/iguanas-floated-one-fifth-of-the-way-around-the-world-to-colonize-fiji/

https://phys.org/news/2025-03-iguanas-world-colonize-fiji-genetic.html

https://www.sciencenews.org/article/iguanas-crossed-pacific-ocean-fiji

https://www.livescience.com/animals/lizards/iguanas-sailed-one-fifth-of-the-way-around-the-world-on-rafts-34-million-years-ago

https://www.discovermagazine.com/planet-earth/iguanas-floated-5-000-miles-to-colonize-fiji-millions-of-years-ago

https://www.iflscience.com/iguanas-rafted-8000-kilometers-from-north-america-to-fiji-a-record-for-land-vertebrates-78450