Southern Black Widow
Latrodectus mactans
Theridiidae (Cobweb Spiders), Order Araneae
Physical Description
Features a rounded, bulbous abdomen and a relatively small cephalothorax. The body is glossy and compact, characteristic of comb-footed spiders.
Size Estimate
Body length around 8 to 13 millimeters for females, with a leg span reaching up to 38 millimeters.
Coloration & Markings
Jet black base coloration with a distinctive red hourglass marking on the underside of the abdomen, though some variations may lack or have broken markings.
Web Type
Irregular, three-dimensional tangle web or cobweb constructed in dark, protected corners close to the ground.
Eye Arrangement
Eight small eyes arranged in two rows of four, typical of the family Theridiidae.
Leg Characteristics
Long, slender black legs without prominent banding, featuring a comb-like row of serrated bristles on the hind tarsi used to pull silk over prey.
Venom & Safety Information
Venom Information
Contains a potent neurotoxin called latrotoxin, which affects the nervous system and causes intense pain and muscle cramping.
Medical Significance
Medically significant. A bite causes severe muscle pain, cramping, rigidity, sweating, and nausea, requiring medical attention though rarely fatal with prompt treatment.
Safety Recommendations
Wear gloves when clearing dark storage areas or moving woodpiles. Relocate spiders carefully using a container if found indoors.
Habitat & Behavior
Habitat & Range
Found primarily in the southeastern United States and warm temperate regions, inhabiting dark, undisturbed crevices, woodpiles, under boxes, and outbuildings.
Behavior & Temperament
Reclusive, non-aggressive, and timid. They typically retreat when disturbed and only bite defensively when trapped or directly pressed against the skin.
Diet & Prey
Feeds primarily on crawling insects such as beetles, ants, roaches, and grasshoppers caught in its sticky web.
Seasonal Activity
Most active during the warm summer and autumn months, often seeking shelter indoors as temperatures drop.
Description
The Southern Black Widow is one of North America's most recognizable spiders, known for the female's glossy black body and signature red hourglass mark. Living quietly in corners and dark retreats, it plays an important insect-controlling role despite its potent venom.
Key Features
Glossy black body, spherical abdomen, and the characteristic red hourglass marking on the ventral side.
Similar Species
False black widows (Steatoda grossa) which lack the red hourglass and have a more purplish-brown coloration.
Life Cycle
Females construct spherical silken 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 pest controller by reducing populations of common household and garden insects.
Conservation Status
Secure and widespread; not currently threatened or evaluated by the IUCN.
Interesting Facts
Females occasionally consume males after mating, a behavior from which the common name 'widow' originates.
Photography Tips
Use a macro lens with good side lighting to highlight the glossy texture and underside markings safely from a distance.
Identified: 2026-09-22T22:05:25.503767