In Wyoming, where it is now, dinosaurs, alligators, and birds’ ancestors once roamed the range. A reptile-like animal with a nose that ate plants around quite a while ago has been depicted in a paper distributed in the journal Variety.
“A New Rhynchosaur Taxon from the Popo Agie Formation, Wyoming” describes the new taxon. Previously, researchers at the University of Wisconsin-Madison discovered “Implications for a Northern Pangean Early-Late Triassic (Carnian) Fauna,” but the surface texture and morphological characteristics of the initial specimens were too eroded for comparison.
Paleontologists were able to confirm it as a brand-new Rhynchosauria by utilizing the distinctive dental morphology of 12 brand-new specimens. There was enough morphological information in five specimens to determine that they belonged to the rhynchosaur subfamily Hyperodapedontinae.
Because the specimens were collected on lands belonging to the Northern Arapaho, the researchers’ First Nation co-authors gave the new animal the taxonomic name Beessiiwo (Bah—se—wa) cooowuse (ja’ aw-wu sa), which translates to “big lizard from the Alcova area” in the Arapaho language. With a length of about half a meter, this massive lizard was small in comparison to the massive reptiles that would later dominate the landscape.
The fossils were found in the Popo Agie Development of Wyoming, a layer of residue stored in the Triassic period in what might have been waterways or lake beds when Wyoming was important for the Northern Pangean supercontinent a huge number of years prior.
Finding the fossils, describing them, and naming the new species may have been simple, but figuring out exactly where they fit into the lizard vocabulary of the Late Triassic Carnian was more difficult. As a result of overlapping definitions based on previous finds, which may be tens of millions of years apart but share traits from common ancestors but are as evolutionarily distant as apes and monkeys, numerous classification schemes have fallen into and out of favor during this time of significant early diversification.
Additionally, even the most devoted paleontologist is baffled by the fact that numerous distinct taxa of these related creatures coexisted in close proximity, shared territories, and occasionally coexisted in some locations. Beessiiwo cooowuse was generally like, and logically a sister type of, the as of late portrayed Oryctorhynchus bairdi tracked down in Nova Scotia, Canada; however, it was anything but a precise match. The researchers decided that Beessiiwo deserved its own category after attempting to fit into any of the available ones.
The authors also mention that Wyoming’s early to late Triassic fauna is yet to be discovered. The Popo Agie Formation stretches from west-central Wyoming through northeastern Utah and parts of Colorado to provide greater surface access to this truly ancient nonmarine continental strata than is found anywhere else in North America.
More information: Adam J. Fitch et al, A New Rhynchosaur Taxon from the Popo Agie Formation, WY: Implications for a Northern Pangean Early-Late Triassic (Carnian) Fauna, Diversity (2023). DOI: 10.3390/d15040544
