Common Spiders in LA
With its warm climate, Los Angeles plays host to several spider species. These spiders can be seen in homes, gardens or the rugged desert terrains bordering the Los Angeles Basin. Though most of the area's spiders are harmless, a few species have poisonous bites. If you're bitten by a spider, call the California Poison Action Line at 800-222-1222 for treatment advice.
California Trapdoor Spider
The California trapdoor spider (Bothriocyrtum californicum) burrows into Los Angeles' soil and creates tunnels with trapdoors, hence its name. Six varieties are common in Los Angeles, according to Pasadena City College, and most measure no more than a half-inch long and are dark brown or black. They usually stay in their tunnels and jump out when prey crawl past their trapdoor.
Brown Recluse Spider
The brown recluse spider (Loxosceles laeta) can be found in eastern Los Angeles, according to the California Poison Control System. The spider measures approximately a half-inch long and is brown or tan with a violin-shaped mark on its head pointing toward its middle. Bites are toxic and cause a burning sensation within 10 minutes, followed by itching. The bite becomes a blister with concentric red-and-white rings.
Cellar Spider
The cellar spider (Pholcus phalangioides) is not native to California but is very common in Los Angeles homes. Pasadena City College attributes the number of house cobwebs to this spider. The spider measures just under an inch and has a brown-gray color with a long, slender abdomen.
Orb Spider
Orb spiders belong to the Argiope family. Common species from the Los Angeles Basin include the golden orb-weaver (Argiope aurantia) and the silver orb-weaver (Argiope argentata), according to the Natural History Museum of Los Angeles County. Brightly colored red or yellow abdomens and unique web shapes make it easy to recognize this species. The spider spins very fine webs that form X-shaped white lines just 3 to 4 feet off the ground.
Tube-Dwelling Spider
The Segestriidae family of spiders are also known as tube-dwelling spiders. They're common in Los Angeles trees, where they spin wool-like webs, according to Pasadena City College. The spider, which is usually dark black with an oval-shaped abdomen and visible fangs, is approximately an inch long. Its leg positions make for a recognizable trait; when resting, the spider pushes its first three pairs of legs forward.
Black Widow Spider
The infamous black widow spider (Latrodectus hesperus) is extremely toxic and especially common in southern California, according to the California Poison Control System. The bite site turns pale and is encircled by a red ring. Physical symptoms include cramps and muscle pain. The spider measures approximately a third of an inch and is glossy black, typically with a bright red spot on its abdomen.
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