Alligator Lizard (e.g. Elgaria multicarinata)

ReptileLizardNorth America

Overview

Alligator lizards (genus Elgaria and relatives) are slender, long-tailed lizards of North and Central America, named for their tough, armoured scales and somewhat broad heads, which give them a passing resemblance to a tiny alligator. The southern alligator lizard (Elgaria multicarinata), shown here, is a common example in the western United States. Their scales are stiffened by bony plates (osteoderms), making the body rather inflexible.

To get around that stiff armour, alligator lizards have a distinctive feature: a fold of loose, soft, granular skin running along each side of the body, which expands to let them breathe, feed, and carry eggs despite the rigid scales.

Note: “alligator lizard” covers several species; details here use the southern alligator lizard as a reference. Treat general statements as approximate and verify against authoritative sources.

Habitat & Range

Alligator lizards live in western North America and into Central America, in a range of habitats — woodland, grassland, chaparral, oak savanna, rocky slopes, and gardens — often in cooler, moister, or more shaded spots than many other lizards prefer. The southern alligator lizard is common in California and adjacent areas, including suburban yards.

Diet

Alligator lizards are carnivores that eat insects, spiders, snails, and other small invertebrates, and larger individuals take small vertebrates such as tiny lizards, baby mice, and eggs, including occasionally raiding birds' nests. They hunt on the ground and in low vegetation, using a strong bite to subdue prey.

Behavior

The lateral skin fold is the key to the alligator lizard's body plan: because the armoured scales make the trunk stiff, the expandable groove of soft skin along each flank allows the body to swell when the lizard breathes deeply, eats a big meal, or fills with eggs. They are mostly ground-dwelling but climb well, and they can shed their long tail to escape a predator, regrowing a shorter replacement. When threatened, an alligator lizard may bite firmly, thrash, and smear the attacker with musk and droppings. They are active by day in mild weather and shelter under logs, rocks, and debris.

Human Interaction & Conservation

Alligator lizards are harmless and beneficial garden residents, helping control insects and other small pests, and they are a familiar sight in parts of the western United States. They are common and adaptable, not generally of conservation concern, though like all wildlife they benefit from intact habitat and from cats being kept indoors. A large one can give a firm but harmless nip if handled. Consult authoritative sources for species-specific status.

More photos of the alligator lizard