The Common Gliding Lizard,
Draco sumatranus, with 'wings' extended
Draco is a genus of agamid lizards that are sometimes called the flying dragons. The ribs and their connecting membrane can be extended to create a kind of wing. The hindlimbs are flattened and wing-like in cross-section, and a small set of flaps on the neck serve as a horizontal stabilizers.
They live in forests, and eat insects. They cannot fly, but often get lift as they glide. Glides as long as 60 m have been recorded, over which the animal loses only 10 m in height. They are quite small. One species is only about 20 cm long.