Labrujasuchus expectatus: 212-Millionen Jahre alte Zahnlose Bipedal Croc-Cousin

Labrujasuchus expectatus, a 212‑million‑year‑old reptile from a New Mexico quarry, shows that a toothless, beaked, bipedal cousin of crocodiles once prowled the Late Triassic.

A New Species in the Shuvosauridae Lineage

The specimen, uncovered in 2006, was dated to 212 Ma, making it younger than one North American Shuvosauridae species and later than others. Alan Turner of Stony Brook University led the team that identified the bones as a new species within Shuvosauridae, noting subtle differences in the humerus and overall morphology.

Anatomical Oddities: Beak, No Teeth, Tiny Arms

Unlike modern crocodiles, L. expectatus had no teeth and a beak‑like snout, raising questions about its diet; Turner suggests it was a meat eater or scavenger, similar to how eagles eat without teeth.

Implications for Archosaur Evolution and Convergent Evolution

Although not a dinosaur, L. expectatus shares convergent traits with theropods, such as bipedalism and a beak, illustrating how similar ecological pressures can produce analogous features across distant lineages. Turner emphasizes that L. expectatus is a distant cousin of modern crocodiles, having split from the lineage that led to alligators and crocodiles hundreds of millions of years ago, making it a side branch rather than a direct ancestor. The discovery, published in the Journal of Vertebrate Paleontology, adds a data point to models of archosaur evolution and helps refine our understanding of convergent evolution during the Late Triassic. Future work will likely focus on further fossil finds to clarify the ecological role of L. expectatus and its place within the broader archosaur tree, potentially reshaping how we interpret the early diversification of bipedal reptiles.

Source: A toothless, beaked, bipedal crocodile cousin roamed Earth 200 million years ago
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