Southern House Spider
Kukulcania hibernalis
Filistatidae (Crevice Weavers), Order Araneae
Physical Description
A robust spider with a velvety or 'felt-like' texture. The abdomen is elongated-oval, and the cephalothorax is relatively flat with a characteristic dark V-shaped or 'violin' marking near the head. They have exceptionally long, thick legs and long, forward-pointing pedipalps (often mistaken for a fifth pair of legs).
Size Estimate
Females are much larger than males, with a body length of 13-19mm (approx. 0.5-0.75 inches) and a leg span reaching up to 2 inches (50mm). This specimen appears to be an adult female.
Coloration & Markings
Females are typically charcoal grey, dusky brown, or black with fine soot-colored hairs. They often have darker markings on the cephalothorax. Males are light amber or yellowish-brown and are frequently misidentified as Brown Recluse spiders.
Web Type
They build messy, non-sticky 'cribellate' silk webs radiating from a central crevice or hole. The silk has a woolly, velcro-like texture that entangles prey through mechanical snagging.
Eye Arrangement
A compact group of eight eyes clustered closely together on a small mound (tubercle) on the front of the cephalothorax.
Leg Characteristics
The legs are long, stout, and covered in dense, fine hairs (setae). They lack the prominent spines found on many other spiders. The front legs are particularly long and are used to sense vibrations in the silk.
Venom & Safety Information
Venom Information
The venom is not considered complex or dangerous to humans. It is primarily designed to immobilize small insects.
Medical Significance
Harmless. A bite might cause minor localized pain similar to a bee sting, but they have no significant medical impact. They are often feared only due to their large size or resemblance to more dangerous species.
Safety Recommendations
If found indoors, they can be safely left alone to catch pests. If relocation is desired, they can be easily captured in a cup and moved to a shed or garage. No special first aid is required for bites beyond standard cleaning.
Habitat & Behavior
Habitat & Range
Common across the Southern United States, from Maryland down to Florida and west to Texas and California. They are synanthropic, frequently found in human structures, particularly in crevices of eaves, shutters, barns, and warehouses.
Behavior & Temperament
They are sedentary, nocturnal ambush hunters that spend most of their lives in or near their silk-lined retreats. They are exceptionally docile and slow-moving, rarely biting even when handled.
Diet & Prey
Primary diet consists of crawling insects such as beetles, cockroaches, and ants. They use their sensitive legs to detect vibrations on their signaling silk-lines before emerging to capture prey.
Seasonal Activity
Active year-round in warmer climates, though they become more noticeable in autumn when males go wandering in search of females.
Description
The Southern House Spider is a common fixture of older buildings in warmer climates. The females are striking for their large, velvety appearance and their tendency to remain in the same crevice for years. They are 'living fossils' belonging to an ancient lineage of spiders.
Key Features
Velvety texture, compact eye cluster on a mound, long pedipalps, and a dark 'violin' mark on the cephalothorax.
Similar Species
Males are frequently confused with the Brown Recluse (Loxosceles reclusa), but can be distinguished by their eight eyes (Recluses have six) and much longer pedipalps. Females may be confused with Wolf Spiders but lack their distinct eye pattern.
Life Cycle
Females are long-lived, sometimes surviving up to 8 years. They produce a white, silken egg sac which they guard within their retreat. Spiderlings may stay with the mother for some time before dispersing.
Ecological Importance
They are excellent natural pest controllers, specializing in capturing large crawling insects that enter homes and barns.
Conservation Status
Not evaluated by the IUCN, but populations are stable and abundant due to their successful adaptation to human-made environments.
Interesting Facts
Unlike many spiders that rebuild webs daily, these spiders may keep the same web for years, simply adding more silk. They are known for being exceptionally calm and are popular among amateur arachnologists.
Photography Tips
Focus on the cephalothorax to capture the eye cluster and the 'violin' mark. These spiders are sensitive to vibrations, so move slowly and avoid touching their radiating silk lines.
Identified: 2026-05-30T21:12:57.437811