Southern Black Widow, Shoe-button Spider
Latrodectus mactans
Theridiidae (Cobweb Spiders), Order Araneae. Key family characteristics include a globular abdomen, comb-like serrated bristles on the hind tarsi used to pull silk over prey, and typically building irregular, tangled web structures.
Physical Description
The spider exhibits a robust, glossy black body with a distinctively large, globular abdomen and a much smaller cephalothorax. The surface is smooth and shiny.
Size Estimate
Body length is roughly 8 to 13 millimeters for females, with a leg span reaching up to 38 millimeters. The specimen appears to be an adult female.
Coloration & Markings
Deep, jet-black coloration with a characteristic bright red or orange hourglass-shaped marking on the ventral (underside) surface of the abdomen.
Web Type
Irregular, three-dimensional tangle web or cobweb constructed close to the ground in dark, undisturbed areas, featuring sticky vertical silk threads that act as tripwires for crawling insects.
Eye Arrangement
Eight small eyes arranged in two parallel rows of four, typical of the family Theridiidae, with anterior and posterior lateral eyes often closely paired.
Leg Characteristics
Long, slender, glossy black legs without prominent banding or spines, featuring specialized comb structures on the hind feet for wrapping prey.
Venom & Safety Information
Venom Information
Neurotoxic venom containing latrotoxin, which affects the nervous system. Potent relative to its size, causing severe systemic symptoms in humans.
Medical Significance
Medically significant. A bite can cause severe local pain followed by muscle cramps, abdominal rigidity, nausea, and sweating. Medical attention should be sought immediately, though fatalities are extremely rare with modern antivenom and supportive care.
Safety Recommendations
Wear gloves when moving woodpiles or stored items in dark areas, shake out shoes before wearing, and gently relocate unwanted spiders outside using a cup and paper.
Habitat & Behavior
Habitat & Range
Found throughout the warmer regions of the United States and parts of the Americas, typically inhabiting dark, dry, sheltered microhabitats such as woodpiles, under stones, hollow stumps, and outbuildings.
Behavior & Temperament
Reclusive, non-aggressive, and sedentary, spending most of its time hanging upside down in its web. It typically bites only in self-defense when accidentally pressed against human skin.
Diet & Prey
Insects and other arthropods such as flies, mosquitoes, beetles, grasshoppers, and caterpillars caught in its sticky snare.
Seasonal Activity
Most active during the warm summer and autumn months, when mating occurs and females produce egg sacs.
Description
The Southern Black Widow is one of North America's most recognizable and misunderstood spiders. Featuring a glossy black finish and a warning red hourglass, this reclusive cobweb weaver prefers quiet corners away from human activity. While its neurotoxic venom demands respect, the spider poses little threat unless directly threatened or compressed.
Key Features
Jet-black glossy body and the unmistakable bright red hourglass marking on the underside of the female's abdomen.
Similar Species
False black widows (Steatoda grossa) and male black widows, which lack the bright red hourglass marking and have different body proportions or brownish patterning.
Life Cycle
Females construct pear-shaped silk egg sacs containing hundreds of eggs. Spiderlings disperse via ballooning after hatching, undergoing multiple molts to reach maturity over several months.
Ecological Importance
Serves as an effective natural controller of insect populations, preying upon common household and agricultural pests.
Conservation Status
Not threatened or endangered; highly adaptable and common throughout its natural range.
Interesting Facts
Despite common myths, female black widows only occasionally consume males after mating, a behavior that gave rise to their common name.
Photography Tips
Use a macro lens with a flash for lighting the dark body, and maintain a safe distance while photographing the ventral side where the diagnostic red hourglass is located.
Identified: 2026-09-21T19:43:22.775148