About Xantusia riversiana Cope, 1883
Nomenclature and Congener Comparison
Commonly known as the island night lizard, Xantusia riversiana Cope, 1883 is significantly larger than the desert night lizard (Xantusia vigilis), another species in the same genus that is found in southern California.
Body Length
Excluding its tail, the island night lizard usually measures between 2.6 and 4.3 inches (6.6 and 10.9 cm) in length.
Lifespan
Its typical lifespan ranges from 11 to 13 years, though some individuals are estimated to have lived 30 years or longer.
Coloration and Patterning
The lizard's base color varies across a spectrum from pale ash gray and beige to brown and black, and its patterning may be uniform, mottled, or striped.
Preferred Habitat
The island night lizard prefers to live in coastal scrub habitats consisting of dense boxthorn and cacti thickets.
Reproductive Mode
Like other night lizards in the family Xantusiidae, the island night lizard is ovoviviparous, meaning it gives birth to live young instead of laying eggs.