Night lizards (family Xantusiidae) are a group of very small, viviparous (live-bearing) scincomorph lizards, averaging from less than 4 cm to over 12 cm long. The family has only three living genera, with approximately 31 living species. The genera are divided by geographic range: Xantusia in southwestern North America and Baja California, Cricosaura in Cuba, and Lepidophyma, the most populous night lizard genus, in Central America.