Ancient Predator Found in Nevada Rewrites Triassic Coastal History

Did you know that Nevada was once submerged under an ancient ocean teeming with marine reptiles?1 A recent fossil discovery in the Augusta Mountains has uncovered a surprising new species: Benggwigwishingasuchus eremicarminis, a 5-6 foot long crocodile-like creature that lived along the coast of the Panthalassan Ocean between 247.2 and 237 million years ago

This terrestrial pseudosuchian archosaur, a relative of modern crocodiles, was unexpectedly found among the remains of ichthyosaurs and ammonites in what was once a pelagic environment. The discovery of B. eremicarminis is rewriting our understanding of ancient coastal life and the diversity of pseudosuchian archosaurs in the early Mesozoic Era.

Unexpected Fossil Find in the Favret Formation

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Image Credit: Smith, N.D.; Klein, N.; Sander, M.P.; Schmitz, L., CC BY 4.0, via Wikimedia Commons

This peculiar creature was unearthed in the Augusta Mountains of Nevada by a team of paleontologists led by Dr. Nate Smith from the Natural History Museum of Los Angeles County

The fossil, a partially articulated skeleton including parts of the skull, spinal column, limb girdles, and limbs, was found in the Middle Triassic Fossil Hill Member of the Favret Formation, a pelagic setting known for abundant ammonites and giant ichthyosaurs like Cymbospondylus youngorum.(ref)

The Favret Formation dates back to the Anisian stage of the Middle Triassic, between 247.2 and 237 million years ago. At that time, the area was submerged under the eastern Panthalassan Ocean, which surrounded the supercontinent Pangaea. Despite Nevada’s current arid, mountainous terrain, this discovery reveals the state’s surprising prehistoric past as a coastal environment.

Evolutionary Revelations & Diversity of Pseudosuchians

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Image Credit: daveynin, CC BY 2.0, via Wikimedia Commons

B. eremicarminis belongs to the crocodilian lineage and its discovery suggests that diverse pseudosuchian archosaurs independently adapted to coastal life during the Triassic period. The evolutionary relationships of B. eremicarminis and its relatives hint that pseudosuchians achieved great diversity rapidly following the End-Permian mass extinction, the extent of which is still being uncovered in the fossil record.

While Triassic pseudosuchians exhibited a wide range of sizes and lifestyles compared to modern crocodilians, B. eremicarminis was likely a medium-sized carnivore, reaching 5-6 feet in length. Its well-developed limbs show no clear adaptations for aquatic life, suggesting it probably stuck close to the shore

The discovery of this terrestrial animal among marine reptiles was initially perplexing for the researchers.

Global Coastal Occupation & Archosauriform Experimentation

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Image Credit: JoergS/DepositPhotos

Interestingly, B. eremicarminis is the first coastal pseudosuchian found in the Panthalassan Ocean realm and western hemisphere, indicating these crocodile relatives inhabited coastal regions worldwide during the Middle Triassic. Other pseudosuchians have been discovered along the shores of the Tethys Ocean (the precursor to today’s Indian Ocean).

However, these various coastal species belong to different evolutionary groups, implying that pseudosuchians and archosauriforms more broadly were independently adapting to shoreline habitats

Dr. Smith describes it as “a bunch of very different archosauriform groups deciding to dip their toes in the water,” showcasing the morphological and ecological diversity and experimentation occurring early in pseudosuchian history.(ref)

What’s in a Name?

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Image Credit: ESTELLE R/Shutterstock

The genus name Benggwigwishingasuchus combines the Shoshone word for “catching fish” with the Greek name for the crocodile-headed Egyptian god Sobek. The species name eremicarminis means “desert song,” a nod to the arid environment where it was found. The name was chosen in consultation with the Fallon Paiute Shoshone Tribe to honor local heritage and reflect the animal’s ecological role and cultural significance.

The discovery of B. eremicarminis is a fascinating glimpse into the unexpected diversity of ancient coastal life. As paleontologists continue to unearth fossils from this time period, who knows what other surprising creatures may emerge to reshape our understanding of the Triassic world?

Source:

  1. Nevada Magazine
davin
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Davin is a jack-of-all-trades but has professional training and experience in various home and garden subjects. He leans on other experts when needed and edits and fact-checks all articles.