Black Widow Spider
Latrodectus mactans
The famous venomous spider with a red hourglass
The black widow is known for the female's glossy black globe abdomen and the red hourglass on its underside. Its neurotoxin is potent, yet it rarely bites humans and does so only when threatened. Males are far smaller and paler.
Key figures
- Length
- Females about 8–13 mm (excluding legs)
- Venom
- Neurotoxic, about 15 times stronger than rattlesnake venom, but injected in tiny amounts
- Life cycle
- Females live about 1–3 years; males only a few months
- Habitat
- Dry, dark corners, rock crevices, woodpiles and storerooms
- Diet
- Insects and other small animals caught in its irregular web
- Feature
- The red hourglass marking on the underside of the abdomen
Life cycle
Egg → Spiderling → Adult
Ecological role
It spins irregular webs in crevices and feeds on flying insects, acting as a common indoor and outdoor predator.
Did you know
Only the female's bite is dangerous to humans; the male is too small and carries too little venom to matter.
Range
North America
Status
Common
Anatomy
- Abdomen — Globular, glossy black, with a red hourglass on the underside — the key identifying mark
- Cephalothorax — Head and thorax fused together, where all eight legs attach
- Eyes — Eight simple eyes in two rows; poor vision but highly sensitive to vibration
- Fangs — A pair of chelicerae ending in fangs that inject neurotoxic venom
- Legs — Eight slender walking legs tipped with claws for moving nimbly on the web
Open the interactive 3D specimen