Anguidae is a large and diverse family of lizards native to the northern hemisphere. The group includes the slowworms, glass lizards, and alligator lizards, among others. Anguidae is divided into three subfamilies and contains 94 species in eight genera. Their closest living relatives are the helodermatid lizards.^[2] They have hard osteoderms beneath their scales, and many of the species have reduced or absent limbs, giving them a snake-like appearance, although others are fully limbed.^[3]

Anguids are carnivorous or insectivorous, and inhabit a wide range of different habitats. The group includes both egg-laying and viviparous species. Most species are terrestrial, although some climb trees.^[3]

Anguids have a relatively good fossil record. The oldest known anguid is Odaxosaurus, from the late Campanian of Canada, approximately 75 million years ago, and anguids are relatively common as fossils the Late Cretaceous and Paleogene of western North America. Odaxosaurus and other Late Cretaceous anguids already exhibit many features found in living anguids, including chisel-like teeth and armor plates in the skin, suggesting a long evolutionary history for the group. Anguids are particularly diverse during the Paleocene and Eocene in North America; some species, such as Glyptosaurus, grew to large size and evolved a highly specialized crushing dentition. The long fossil record for Anguidae in North America suggests that the group probably evolved in North America during the Cretaceous before dispersing to Europe in the Paleogene.

Classification

Helodermoides tuberculatus fossil

Family Anguidae

• Subfamily Anguinae
  • Genus Anguis - Slow worms (2 species)
  • Genus Ophisaurus - Glass lizards (13 species)
  • Genus Pseudopus - Scheltopusik (1 species)
• Subfamily Diploglossinae
  • Genus Celestus - Galliwasps (25 extant species)
  • Genus Diploglossus - Galliwasps (19 species)
  • Genus Ophiodes - (4 species)
• Subfamily Gerrhonotinae - Alligator lizards
  • Genus Gerrhonotus (4 species) - Alligator lizards
  • Genus Abronia (27 species) - Arboreal alligator lizards

References