Theridiidae (cobweb weavers)

The Black Widow

Latrodectus mactans

Dangerous

Photo: Shenrich91 · CC BY-SA 3.0 · Wikimedia Commons

Family

Theridiidae (cobweb weavers)

Size

Body 8–13 mm (female)

Region

Americas, temperate worldwide

Habitat

Woodpiles, sheds, undisturbed dark spaces and garden debris.

Overview

Glossy black with the unmistakable red hourglass. Its neurotoxic venom makes it the most medically significant spider in North America.

Standout fact

Black widow venom is roughly 15× more potent drop-for-drop than a rattlesnake's, but the dose delivered is tiny.

Parasteatoda tepidariorum

The spider you most often meet indoors. It builds tangled cobwebs in quiet corners and is completely harmless to people.

Loxosceles reclusa

A shy, reclusive hunter recognised by the dark violin shape on its back. Its cytotoxic venom can cause slow-healing wounds.

Phidippus audax

Charismatic, curious and fuzzy, with huge forward-facing eyes. It hunts by pouncing rather than building webs.

Trichonephila clavipes

Spins enormous webs of shimmering golden silk. Large and dramatic, yet shy and reluctant to bite.