Ancient lizard and snake catalogue A to Z

Squamates are more than a modern silhouette

The catalogue combines several branches of Squamata without treating them as one linear sequence. Adriosaurus and Aigialosaurus entered marine settings in different ways, while the other animals are terrestrial.

One specimen can be valuable and limiting

Aigialosaurus and Aiolosaurus are each securely represented by one principal specimen. Their bones can diagnose anatomy, but cannot reveal the full variation of a population.

Teeth describe mechanics before menus

The broad-based teeth of Adamisaurus and three-cusped crowns of Asagaolacerta indicate different food-processing systems. Neither shape alone identifies a particular plant, insect or shell.

Classification changes when fossils improve

A newer skeleton of Ardeosaurus supplied details missing after the holotype was lost. Its position still varies among analyses, illustrating why a phylogenetic result is a testable hypothesis rather than a permanent label.

Reading marine adaptations

Limb reduction in Adriosaurus was uneven, while Aigialosaurus retained four digit-bearing feet. Both relied heavily on the trunk and tail, but neither should be reconstructed automatically as a miniature late mosasaur.