Lizard is the common name used for all squamate reptiles that are not snakes, encompassing over 7,000 species. They have a cosmopolitan distribution, ranging across all continents except Antarctica, as well as most oceanic island chains. Extant lizard species vary in size from the 13.5 mm (0.53 in) nano-chameleon and the 14–18 mm (0.55–0.71 in) Jaragua dwarf gecko to the 3-meter-long Komodo dragon.