Types of Lizards in Los Angeles: 3 Species Living in Your Backyard
October 26, 2026
Anyone researching the types of lizards in Los Angeles quickly discovers that the county’s reptile life is far richer than the coyotes and hawks usually associated with the region. Tucked into hillside chaparral, cracked sidewalks, and porch lights across the metro area, a small cast of lizard species has quietly become part of daily city life. Some have lived here for thousands of years; others arrived by accident and never left.
This guide covers the three lizards Angelenos are most likely to encounter: the southern alligator lizard, the western fence lizard, and the Mediterranean house gecko. Each one has adapted to Los Angeles in a different way, and knowing how to tell them apart makes backyard wildlife-watching a lot more interesting.
1. Southern Alligator Lizard
The southern alligator lizard (Elgaria multicarinata) is the species most likely to catch a homeowner off guard, because it does not just tolerate city life, it thrives in it. According to a survey of the Baldwin Hills, the Southern Alligator Lizard is one of the most widespread urban dwelling lizards based on observations reported by citizens in the Los Angeles basin, and researchers found it in most areas surveyed, particularly cooler, densely vegetated spots.
UCLA reptile expert Brad Shaffer, who studies urban wildlife in Southern California, has called the species a bit of a puzzle precisely because of how well it does in cities. “Southern alligator lizards are a little bit of a mystery, because they’re our most-urban-adapted species,” Shaffer said. He added that they do well in parks and backyards and are “a great addition” to the city’s wildlife, calling it “a beautiful lizard.”
Size is one of the easiest identifiers. Southern alligator lizards can be up to a foot long, with most of their length coming from their tails, which they can use to help them climb, a sort of fifth limb. That long, muscular tail combined with a boxy, armored body is what gives the species its “alligator” nickname. Despite the tough appearance, Shaffer is quick to reassure worried residents: “They’re great animals: They’re harmless, they’re useful, they’re a native species and they can’t hurt you,” he said, noting that “they help by eating all kinds of insects, including pest insects.”
They can deliver a pinch if handled carelessly, but as Shaffer discovered after getting bitten repeatedly while showing one to news cameras, the bites “can’t break the skin, they just pinch.” If one wanders indoors, the recommended approach is simple: “just get a broom and gently coax them toward the door.”
Pro Tip: A quick way to rule out a snake is checking for legs, external ear openings, and moveable eyelids. Unlike snakes, lizards have external ear openings and moveable eyelids, which alligator lizards display clearly even when their short legs are tucked close to the body.
The southern alligator lizard belongs to a family found well beyond California, and readers curious about how related species look and behave elsewhere can compare notes with the alligator lizards native to Mexico, where several close relatives occupy similar hillside and garden habitats.
2. Western Fence Lizard
The western fence lizard (Sceloporus occidentalis) is better known by its nickname, the blue-belly, thanks to the coloring on adult males. The males have distinctive iridescent patches of candy-metallic blue along their flanks, which they flash during territorial push-up displays. Across the state, this species holds the title of most frequently spotted lizard: the western fence lizard is by far the most commonly-encountered lizard in California, showing up in yards, agricultural areas, and open hillsides alike.
Interestingly, western fence lizards do not dominate the urban core the way alligator lizards do. Shaffer’s UCLA research team observed the opposite pattern from what many residents might expect: “Western fence lizards are much more abundant in Southern California, but they’re not thriving as well in cities,” he said, adding that the native alligator lizards’ success is a sign that something is being done right environmentally to support them. In other words, fence lizards are common across greater Los Angeles, but they favor open, less developed terrain over dense residential blocks.
Beyond their role in the local food web, western fence lizards perform a public health service that few residents realize. A 1998 study led by UC Berkeley entomologist Robert Lane found that a protein in the western fence lizard’s blood killed Borrelia bacteria, and as a result, Lyme-infected ticks that feed on the lizard’s blood are cleansed of the disease-causing pathogen. That matters because up to 90 percent of the juvenile ticks in this species feed on the western fence lizard, which is prevalent throughout California and neighboring states. As a result, the lizard is often credited for the relatively low incidence of Lyme disease in the Western United States.
Key Insight: The same “disease-cleansing” trait has since been documented in other local reptiles. Cal Poly researcher Emily Taylor found that the effect is “not just the western fence lizard; locally, it also includes other species like alligator lizards,” meaning both of Los Angeles’s most common native lizards may be quietly protecting residents from tick-borne illness.
Because the western fence lizard’s range stretches far beyond California, readers who want to compare its habits with populations elsewhere can look at the desert lizards found in Arizona or the fence lizard populations across Texas, both of which host related Sceloporus species adapted to drier terrain.
3. Mediterranean House Gecko
Unlike the previous two species, the Mediterranean house gecko (Hemidactylus turcicus) is not native to Southern California. Found in the Southeast and Los Angeles, California, this species, as its name would suggest, is not native to California. It likely arrived through nursery stock or shipping and has since settled comfortably into porches, stucco walls, and streetlights across the region.
Size and coloring make this gecko fairly easy to distinguish from the two native species. Mediterranean house geckos grow to about 1.5 to 2.5 inches (3-6 cm) and have a life expectancy of 3-9 years. Physically, they are small and delicate looking, with flattened bodies and protruding tubercles on their skin. A close look reveals another giveaway: large vertical pupils and no eyelids, a trait shared with many gecko species but absent in fence and alligator lizards.
Color also shifts depending on the time of day. The lizards’ bodies are a pinkish translucent color in their light phase and a darker grayish color when in the dark phase. That pale, almost ghostly appearance is one reason these geckos are so easy to spot clinging to a porch light after dark.
Mediterranean house geckos are strictly nocturnal, and their hunting strategy is refreshingly low-effort. They like to sit still under a light source at night and wait for insects attracted to the light. Males are also vocal during the breeding season: they make squeaking noises during fights and to attract mates. Residents who hear faint chirping near an exterior light after dark are almost certainly listening to one of these geckos rather than an insect.
This species is part of a broader pattern that Los Angeles biologists have been tracking for years. The Natural History Museum of Los Angeles County runs a community science initiative that documents exactly these kinds of arrivals. Since its initiation in 2013, the RASCals (Reptiles and Amphibians of Southern California) Community Science Project has led to the discovery of more than a dozen new populations of lizards living in Southern California, and researchers note that these lizards don’t belong here; they’ve come from other parts of the world and could negatively impact local species by preying upon smaller species or outcompeting them.
Important Note: The Mediterranean house gecko is not the only non-native lizard turning up in Los Angeles backyards. NHM scientists have also confirmed established populations of green anoles in neighborhoods like Hancock Park, a species native to the southeastern United States. Anyone who spots an unfamiliar lizard is encouraged to report it through the museum’s community science program rather than assuming it is harmless to local ecosystems.
Because this same gecko has spread well beyond California, readers can see how it behaves in other warm climates through resources on house geckos established in Florida or, for a look at how introduced reptiles fare on islands, the invasive geckos found in Hawaii.
4. Comparing the Three Species at a Glance
A common question among new Los Angeles homeowners is how to quickly tell these three lizards apart without waiting for a field guide. The table below breaks down the fastest identifiers.
| Feature | Southern Alligator Lizard | Western Fence Lizard | Mediterranean House Gecko |
|---|---|---|---|
| Native status | Native | Native | Introduced |
| Typical size | Up to 12 inches | Small to medium, spiny scales | 1.5 to 2.5 inches |
| Active time | Daytime | Daytime | Nighttime |
| Common location | Dense vegetation, backyards, parks | Fence posts, rocks, open hillsides | Porch lights, stucco walls, exteriors |
| Notable trait | Long climbing tail | Blue belly patches, Lyme disease protection | No eyelids, squeaking calls |
None of these three species pose any real danger to people or pets. In fact, only one Californian lizard species possesses venom, and it lives in the state’s deserts, not the Los Angeles basin. Readers curious about venomous lizards can compare the trait in the venomous Mexican beaded lizard, a close relative of the desert-dwelling Gila monster.
Los Angeles County’s reptile diversity does not stop at these three. Statewide, California has more than sixty different species and subspecies of lizards, and the most common are alligator lizards and fence lizards (also called bluebellies). The county also hosts less common residents such as the side-blotched lizard and the Italian wall lizard, a species documented in San Pedro. For readers interested in how neighboring states compare, guides covering fence lizard populations in Georgia offer a useful East Coast contrast to the Southern California scene.
Why These Lizards Matter to the Local Ecosystem
Every one of these species plays a working role in the neighborhoods where it lives, not just a decorative one. Alligator lizards and fence lizards keep insect populations in check, and as noted earlier, fence lizards specifically help suppress Lyme disease transmission by cleansing feeding ticks of harmful bacteria. Mediterranean house geckos, while non-native, also feed heavily on insects drawn to artificial light, though biologists still weigh that benefit against the risk they pose to native species through competition.
Anyone who wants to go beyond backyard observation and start keeping reptiles at home should research species-specific care before bringing one in, since wild-caught native lizards generally should be left where they are found. A broader overview of popular pet reptiles is a useful starting point for readers considering a captive-bred gecko or lizard species instead.
Common Mistake: Many residents assume any small lizard darting across a patio at night must be dangerous or invasive by default. In reality, only the Mediterranean house gecko among these three is non-native, and even that species poses no direct threat to humans.
Final Thoughts on Los Angeles Lizards
Los Angeles residents share their neighborhoods with a small but resilient set of lizard species, each filling a distinct role. The southern alligator lizard has proven itself the city’s most adaptable native, the western fence lizard quietly protects public health while favoring open terrain over dense blocks, and the Mediterranean house gecko has carved out a nocturnal niche around porch lights despite its non-native origins. Recognizing these three species, and understanding what each one contributes to the local ecosystem, turns a routine backyard sighting into a small window on how wildlife survives, and sometimes thrives, in one of the country’s largest cities.