Brown Widow

Latrodectus geometricus

True spideradvancedVenom: Medically significant

Medically significant venom

Venom is medically significant. Experienced keepers only — check local legality and have a protocol.

About

A tan, mottled widow with a striking orange hourglass — a hardy, low-maintenance cobweb-builder, but one for experienced, cautious keepers only. Its venom is the same type as the black widow's (latrodectism) and is medically significant, so it requires escape-proof housing and absolutely no handling; in practice brown widow bites tend to be milder and more localized than black widow bites because far less venom is delivered, but it must still be treated with full respect. Give a tall enclosure with anchor points for its irregular web, room temperature, occasional misting for water, and crickets or flies. Shy and reluctant to bite. Solitary.

Taxonomy

FamilyTheridiidae

GenusLatrodectus

Native regionCosmopolitan in warm regions; widespread in the southern USA

TypeCobweb (web)

Temperamentshy, reclusive; venom is MEDICALLY SIGNIFICANT — no handling

Size & growth

Adult sizefemale 7-10 mm, male ~4 mm

Length4.00–15.00 mm

Growth ratefast

Climate

Temperature70–85 °F

Humidity50–65%

Enclosure

Adult size8x8x10 in or 32oz, vertical web anchors

Substrateanchor points (sticks, cork, mesh) for an irregular cobweb; substrate optional

Substrate depth1-2 inches (web spider; rarely on the ground)

Water dishOptional

Feeding

Feeding modePredator (live prey)

Prey sizeflying insects, crickets

Adult cadence2-3 prey per week

Times kept: 0