Southern Black Widow, Shoe-button Spider
Latrodectus mactans
Theridiidae (Cobweb Spiders), Order Araneae
Physical Description
Small to medium-sized spider with a smooth, glossy, bulbous spherical abdomen and a distinctively smaller cephalothorax. The silhouette shows slender legs radiating from a compact central body mass.
Size Estimate
Body length ranges from 8 to 13 millimeters for adult females, with a leg span up to 38 millimeters. The specimen appears relatively small against the screen mesh, likely an adult female or a larger juvenile.
Coloration & Markings
Jet black base coloration with a high-gloss finish. While details are silhouetted against the bright background, this species typically features a distinctive red or orange hourglass marking on the ventral side of the abdomen.
Web Type
Irregular 3D tangle web or cobweb constructed near ground level in dark, undisturbed areas, featuring a sticky, scaffolding-like structure.
Eye Arrangement
Eight small eyes arranged in two rows of four, typical of the Theridiidae family, set closely together on small tubercles on the anterior cephalothorax.
Leg Characteristics
Long, slender, smooth legs without prominent spines, though the hind legs possess a comb-like row of serrated bristles used to pull silk over prey.
Venom & Safety Information
Venom Information
Neurotoxic venom containing latrotoxin, which affects the nervous system and causes severe muscle cramps and pain.
Medical Significance
Medically significant. Bites can cause severe local pain spreading to the abdomen and back, sweating, and nausea. Antivenom is available for severe cases, though most healthy adults recover fully with medical care.
Safety Recommendations
Wear gloves when moving firewood or cleaning dark corners. If found indoors, relocate safely using a container or contact pest control if near high-traffic living areas.
Habitat & Behavior
Habitat & Range
Found throughout the warmer regions of the United States, particularly the South and West, inhabiting sheltered, dark nooks around woodpiles, under stones, and around human structures.
Behavior & Temperament
Timid and non-aggressive, typically retreating when disturbed. They spend most of their time hanging upside down in their webs and only bite in self-defense when accidentally pressed against human skin.
Diet & Prey
Insects such as flies, mosquitoes, grasshoppers, beetles, and caterpillars that become entangled in the sticky lower threads of the web.
Seasonal Activity
Most active during the warmer months of spring, summer, and early autumn, seeking sheltered over-wintering spots when temperatures drop.
Description
The Southern Black Widow is one of North America's most recognizable spiders, known for its glossy black body and potent neurotoxic venom. Preferring quiet, undisturbed corners, it plays a vital role in controlling insect populations.
Key Features
Glossy jet-black body, spherical abdomen, and the characteristic red hourglass marking on the underside.
Similar Species
False widow spiders (Steatoda species) and male or juvenile black widows, which often feature red or white spots on the dorsal side instead of a clean black body.
Life Cycle
Females construct multiple pear-shaped silk egg sacs containing hundreds of eggs. Spiderlings disperse via ballooning after hatching, undergoing multiple molts to reach maturity.
Ecological Importance
Acts as an effective natural predator of pest insects, helping to naturally regulate populations of flies, roaches, and agricultural pests.
Conservation Status
Not threatened or endangered; highly adaptable and common throughout its native range.
Interesting Facts
Females occasionally consume males after mating, giving the species its widow moniker, though this behavior is less common in the wild than in laboratory settings.
Photography Tips
Use a macro lens from a safe distance with natural sidelighting to capture the glossy texture and the ventral hourglass marking without disturbing the spider.
Identified: 2026-09-18T22:59:16.975026