Southern Black Widow
Latrodectus mactans
Theridiidae (Cobweb Spiders), Order Araneae. Key family traits include a globose abdomen and building 'tangle' webs.
Physical Description
A shiny, jet-black spider with a spherical, bulbous abdomen and a smaller cephalothorax. The exoskeleton has a high-gloss, porcelain-like texture.
Size Estimate
Body approx. 8-13 mm for females; leg span up to 38 mm (1.5 inches). This specimen looks to be an adult or sub-adult female.
Coloration & Markings
Deep, glossy black overall. While the red hourglass on the underside is not visible here, the dark, unpatterned dorsal view is classic for the adult female of this species.
Web Type
Irregular, messy-looking 'tangle' or 'cobweb' built in dark, recessed areas. The silk is exceptionally strong and 'pings' when broken.
Eye Arrangement
8 eyes in two rows of four; however, they are small and difficult to see without extreme magnification/macro photography.
Leg Characteristics
Long, slender legs tapering to a point. The fourth pair of legs has a row of serrated bristles (comb-foot) used to wrap prey in silk.
Venom & Safety Information
Venom Information
Contains 'alpha-latrotoxin,' a potent neurotoxin that causes massive release of neurotransmitters. It is medically significant but rarely fatal to healthy adults.
Medical Significance
Dangerous. Bites cause 'latrodectism'—severe muscle pain, abdominal cramping, and sweating. Seek medical attention if bitten; antivenom is available.
Safety Recommendations
Wear gloves when working near well heads or woodpiles. Do not reach into dark spaces blindly. Relocate using a jar and stiff paper if necessary.
Habitat & Behavior
Habitat & Range
Found throughout the Southeastern US, including North Carolina. Prefers dark, undisturbed places like woodpiles, sheds, and well heads.
Behavior & Temperament
Reclusive and shy. They prefer to retreat into a crevice rather than bite. They are primarily nocturnal and stay within or near their web.
Diet & Prey
Insects like beetles, roaches, and grasshoppers. They use their strong silk to entangle prey before delivering a paralyzing bite.
Seasonal Activity
Most active from late spring through autumn. They may overwinter in protected structures like the well head in this photo.
Description
The Southern Black Widow is one of North America's most iconic venomous spiders. They are recognized by their sleek, oily-black appearance and sedentary lifestyle.
Key Features
Glossy black spherical abdomen, messy tangle web, and the classic red hourglass on the ventrum (underside).
Similar Species
Steatoda grossa (False Widow) lacks the red marking and has a more purple-brown tint. Latrodectus variolus (Northern Widow) has a broken hourglass.
Life Cycle
Females produce papery, tan/white egg sacs containing hundreds of eggs. Spiderlings disperse via 'ballooning.' Females can live up to 3 years.
Ecological Importance
Highly effective at controlling pest populations including cockroaches and beetles that common garden spiders might miss.
Conservation Status
Stable; not listed by IUCN. They thrive in human-altered environments where debris provides shelter.
Interesting Facts
Despite the name, sexual cannibalism is not mandatory or even common in the wild; males often survive mating by sensing if the female is well-fed.
Photography Tips
A side or 'ventral' (underneath) shot is best to confirm the red hourglass. Use a flash to highlight the glossy texture of the abdomen.
User Notes
Found under well head in North Carolina
Identified: 2026-06-10T23:38:26.699593