Paleontology: Tiny prehistoric lizard sheds light on reptile evolution

The discovery of a new species of prehistoric reptile from Germany is reported this week in Scientific Reports. The anatomical features of the species, named Vellbergia bartholomaei, add to our understanding of the early evolution of lepidosauromorphs.

Lepidosauromorphs are one of the largest and most diverse tetrapod lineages with over 10,500 species. Ancestors to modern-day lizards, snakes and reptiles known as tuataras, lepidosauromorph specimens have only been found across a few Triassic sites and their early evolution remains largely unknown.

Gabriela Sobral and colleagues discovered the small fossil within the Middle Triassic (247 to 237 million-year-old) deposits of Vellberg, Germany. Analyses suggest that the specimen is a previously unknown species of early lepidosauromorph. One of the smallest found at the site, it could represent the first juvenile fossil collected at Vellberg. V. bartholomaei differs from other lepidosauromorph species owing to its distinct characteristics, including narrow, slender and short teeth relative to the lower jaw, but shares a mosaic of features found in the predecessors of present-day lizards and tuataras. The findings, which suggest that Vellbergia may be a common ancestor of the two lineages, further our understanding of early reptile evolution.

The fossil adds to evidence implicating Vellberg as an important site for understanding early lepidosauromorph evolution. Owing to the poor fossil record for the Early Triassic period, specimens from the Middle Triassic are of fundamental importance to understanding how vertebrates recovered after the Permian-Triassic mass extinction (around 252 million years ago), the Earth's most severe known extinction event, and how they diversified into modern species.

Credit: 
Scientific Reports