Sauria

• Iguanidae

  New World lizards.

• Agamidae

  An Old World reptile family of Sauria.

• Scincidae

  Skinks.

• Anguidae

  Alligator lizards.

• Teiidae

  Whiptails; etc.

• Gekkonidae

  Geckos.

• Helodermatidae

  Only known venomous lizards.

• Lacertidae

  Old World lizards.

• Chamaeleontidae

  Old World chameleons; in some classifications they are considered a superfamily...

• Pygopodidae

  Australian and Tasmanian lizards.

• Xantusiidae

  Night lizards.

• Xenosauridae

  Monotypic family of Mexican lizards.

• Anniellidae

  Legless lizards.

• Lanthanotidae

  Stout-bodied lizards.

• Varanidae

  Monitor lizards.

• Amphisbaenidae

  Worm lizards.

Serpentes

• Colubridae

  Nonvenomous snakes; about two-thirds of all living species.

• Elapidae

  Cobras; kraits; mambas; coral snakes; Australian taipan and tiger snakes.

• Crotalidae

  New World vipers: pit vipers.

• Boidae

  Boas and pythons.

• Viperidae

  Old World vipers.

• Leptotyphlopidae

  Blind snakes.

• Hydrophidae

  Sea snakes.

• Typhlopidae

  Blind snakes.

Chelonia

• Emydidae

  Box and water turtles.

• Testudinidae

  Land tortoises.

• Cheloniidae

  Green turtles; hawksbills.

• Chelydridae

  Snapping turtles.

• Kinosternidae

  Mud turtles; musk turtles.

• Trionychidae

  Soft-shelled turtles.

• Dermochelyidae

  Sea turtles.

Crocodylia

• Crocodylidae

  True crocodiles.

• Alligatoridae

  Alligators; caimans.

• Gavialidae

  Gavials.

Euronithopoda

• Hadrosauridae

  Duck-billed dinosaurs; upper Cretaceous.

• Iguanodontidae

  Iguanodons.

Also contains

• Dromaeosauridae

  Swift-running bipedal dinosaurs.

• Pythoninae

  Old World boas: pythons; in some classifications considered a separate family from B...

• Titanosauridae

  Herbivorous dinosaurs of the Cretaceous.

• Ichthyosauridae

  Later ichthyosaurs of the Jurassic and Cretaceous; widely distributed in both h...

• Megalosauridae

  Megalosaurs.

• Edaphosauridae

  A family of reptiles of the order Pelycosauria.

• Pterodactylidae

  A reptile family in the order Pterosauria.

• Pythonidae

  In some classifications a family separate from Boidae comprising Old World boas.

• Ceratopsidae

  American ceratopsian dinosaurs.