Gekkonidae:

In general, geckos may be divided into 2 primary groups: species with immovable, or fixed, eyelids (Gekkoninae, Teratoscincinae, and Diplodactylinae), and species which possess a movable eyelid (Aleuroscalabotinae & Eublepharinae). Geckos which possess fixed eyelids can be further divided on the basis of the presence (arboreal), or lack of presence (generally terrestrial), of sub-digital lamellae. Normally, the tail length of most gecko species is nearly equal to the snout-vent length and is expressed in a great variety of textures, shapes, and sizes. Additionally, the presence of either round pupils (diurnal) or vertically oriented pupils (nocturnal) helps to distinguish several genera. A number of arboreal species exhibit a stunning degree of beautiful green, red, and blue coloration (notably, species of Phelsuma and Naultinus). Finally, scalation characteristics range from the tile-like network (smooth, cycloid, imbricate) to be found on Teratoscincus, Geckolepis, and Teratolepis, to among some of the most minute, velvety-textured, granular scales exhibited in several Oedura species.