The desert night lizard, Xantusia vigilis, is a night lizard native to southern California east of the Sierras and San Gabriel Mountains into Baja California, southern Nevada, southwestern Utah and extreme western Arizona.
Like all night lizards, the desert night lizard is viviparous, giving birth to live young and producing 1 to 3 young from August to December. The desert night lizard attains a snout-to-vent length (SVL) of 1.5 to 2.75 in (3.8 to 7.0 cm) with a tail roughly the same length. The lizard’s coloring is usually gray, yellow-brownish, or olive. Despite their name, night lizards are active during the day. They are known to easily to change their color, from light olive (usually during the evening) to dark brown during the day. It is a good climber and usually eats termites, small insects, spiders and other arthropods.
It is a secretive lizard of arid and semi-arid locales. During the day it may be found under fallen debris of desert plants and in rock crevices. It is usually associated with varieties of yucca such as the Joshua Tree, Spanish Dagger, and Spanish Bayonet.
Unusually for a lizard it forms family social groups with a father-mother pair and offspring, which may delay dispersing for years. The young are capable of feeding themselves but will huddle together with their relatives. They do not receive any direct care from their parents and older siblings and it is not yet known what the advantages of staying with their parents are. The baby lizards are well-camouflaged and are not much bigger than a toothpick.