Types of Spiders Commonly Found in Southern California

Southern California is home to a diverse array of spider species, each with its own behaviors and risks. Understanding these common invaders is the first step in effective spider control.

Black Widow Spiders (Latrodectus hesperus)

• Identification: Famous for the female’s shiny black body and distinctive red hourglass marking on the underside of her abdomen. Males are smaller and lighter in color.
• Behavior: Primarily nocturnal, black widows prefer dark, secluded areas like woodpiles, garages, sheds, and under eaves. Their webs are irregular and strong.
• Specific Risks: Their venom is neurotoxic and can cause severe pain, muscle cramps, nausea, and sweating. While bites are rarely fatal, they require immediate medical attention.

Brown Widow Spiders (Latrodectus geometricus)

• Identification: Similar in shape to the black widow but typically lighter in color, ranging from tan to dark brown, with an orange or yellow hourglass marking. Their egg sacs are spiky.
• Behavior: Often found in similar outdoor locations as black widows, but also more commonly in cluttered areas around homes, patio furniture, and mailboxes.
• Specific Risks: Their venom is also neurotoxic, though generally less potent than the black widow’s. Bites can still cause localized pain and discomfort.

Wolf Spiders (Family Lycosidae)

• Identification: Large, hairy, and fast-moving spiders, typically brown or gray with distinct markings. They do not build webs to catch prey.
• Behavior: Hunters that actively pursue their prey on the ground. They are often found in gardens, leaf litter, and sometimes wander indoors, especially during cooler weather.
• Specific Risks: While their bite is not considered dangerous, it can be painful and cause localized swelling and redness.

Orb Weaver Spiders (Family Araneidae)

• Identification: A large family with many species, known for building elaborate, circular (orb) webs. They vary greatly in size and color.
• Behavior: Construct their webs in open areas, often between plants, trees, or structures, to catch flying insects. They are generally harmless to humans.
• Specific Risks: Bites are rare and typically only occur if provoked. Their venom is not considered medically significant.

Jumping Spiders (Family Salticidae)

• Identification: Small to medium-sized, often hairy, with excellent eyesight and a distinctive jerky, jumping movement. Many species are brightly colored.
• Behavior: Active hunters that stalk and pounce on their prey. They are commonly seen on walls, fences, and plants, and occasionally enter homes.
• Specific Risks: Bites are uncommon and generally cause only mild, localized irritation.

Cellar Spiders (Pholcus phalangioides)

• Identification: Also known as “daddy long-legs,” these spiders have very long, thin legs and small, elongated bodies.
• Behavior: Build loose, irregular webs in damp, dark areas like basements, cellars, and crawl spaces. They are harmless to humans.
• Specific Risks: Not considered medically significant.