Insect identifier · Spiders and scorpions
How to identify a Western black widow
Latrodectus hesperus
· Also called black widow, western widow, black widow california, black widow arizona

Western black widows thrive in western suburbs, parks, and irrigation edges. Same hourglass logic as other widows.
Someone searching this page usually has a western black widow in a photo, on skin, or in a story about yards, garages, parks. Use the marks, the bite, and the range together. Western black widows thrive in western suburbs, parks, and irrigation edges. Same hourglass logic as other widows.
What does a western black widow look like?
Shiny black female, red hourglass, messy cobwebs under pot lips and playground equipment.
Western black widow (Latrodectus hesperus) is Similar to southern widow. Colors people notice: black, red. Field marks: Shiny black female, red hourglass; Common around western homes and playground equipment; Messy cobwebs in corners and under lips of pots. It is found both. If those marks are missing, open Southern black widow, Northern black widow before you force this name. Search phrases that belong on this page include what a western black widow looks like and western black widow identification.
Identification marks
- Shiny black female, red hourglass
- Common around western homes and playground equipment
- Messy cobwebs in corners and under lips of pots
Size: Similar to southern widow
Colors: black, red
Where: both
What a typical western black widow bite looks like

Small mark, possible systemic muscle pain. Treat systemic symptoms as urgent.
People searching “western black widow bite identification” want the pattern, not a single anonymous bump. Same widow pattern: small mark, possible systemic muscle pain. Immediate steps on this page: Urgent care for systemic symptoms; Clean and ice locally; Photo the spider if possible. This species does bite or sting people. Fever, spreading redness, trouble breathing, or a child with many stings is professional care.
If you were bitten
- Urgent care for systemic symptoms
- Clean and ice locally
- Photo the spider if possible
Western black widow vs Southern black widow
Same hourglass rule as other widows. In the West they show up in playground equipment and pot rims. False widows in the same sheds lack the red hourglass.
- Southern black widow identification (Latrodectus mactans)
- Northern black widow identification (Latrodectus variolus)
- False widow identification (Steatoda grossa)
- Brown widow identification (Latrodectus geometricus)
Range and season
Western North America, warm months.
Western suburbs, irrigation edges, parks, and sheds.
Western North America, including dry urban edges and deserts.
Warm months
Common questions
Are western black widows common in cities?
Yes, they thrive in western suburbs, parks, and irrigation edges.
Is the bite worse than a bee sting?
It can be, because of neurologic venom — treat systemic symptoms as urgent.
Do males bite?
Rarely of medical importance.
Are there black widows in California and Arizona?
Yes. Western black widows are common around western homes and parks.
Western black widow vs false widow?
True widow: black with red hourglass. False widow: brown bulbous abdomen, no red hourglass.
Related identification pages
- Southern black widow identification
- Northern black widow identification
- False widow identification
- Brown widow identification
- Brown recluse identification
- Yellow sac spider identification
- Yellow garden spider identification
- Arizona bark scorpion identification
- All insect identification pages
- Identify an insect from a photo
