Tholosauridae

Tholosauridae is an extinct family of procolophonid reptiles that lived during the Late Triassic period. These small, herbivorous animals were part of the earliest radiation of lepidosaurs, a group that also includes modern lizards and snakes. Tholosaurids are characterized by their robust build, short tails, and relatively broad skulls. Their teeth suggest a diet of tough plant material, and their limb structure indicates they were likely terrestrial, possibly adapted for digging or moving through dense vegetation. Fossils of tholosaurids have been found in several continents, including Europe, Africa, and South America, suggesting a relatively widespread distribution during their existence.

The family Tholosauridae includes a few genera, most notably Tholacosaurus and Palaeochersis. These genera display variations in skull morphology and vertebral structure, reflecting some degree of diversification within the group. Their ecological niche likely involved foraging on low-lying plants in arid or semi-arid environments. As procolophonids, tholosaurids represent an important lineage in understanding the early evolution of diapsid reptiles, a major group that dominated Mesozoic ecosystems. The extinction of tholosaurids, like many other Triassic fauna, is often linked to the end-Triassic extinction event, which significantly reshaped terrestrial vertebrate communities. Studying tholosaurids provides insights into the palaeoecology and evolutionary history of early terrestrial ecosystems.