Woodlouse Hunter, Sowbug Killer, Woodlouse Spider
Dysdera crocata
Dysderidae (Woodlouse Hunters), Order Araneae. Characterized by having only six eyes and large, forward-jutting chelicerae (fangs).
Physical Description
A medium-sized spider with a smooth, glossy texture. The cephalothorax is reddish-brown to dark orange, and the oval-shaped abdomen is a pale, creamy grey or tan. It possesses exceptionally large, prominent chelicerae (fangs) that project forward, adapted for piercing the armor of isopods.
Size Estimate
Body length typically ranges from 9-15 mm (approx. 0.4-0.6 inches). Common for adult females to be larger than males. This specimen appears to be an adult.
Coloration & Markings
Characteristically bi-colored: the head/thorax and legs are a deep mahogany or rusty orange, while the abdomen is a dull, uniform cream or yellowish-grey without distinct patterns.
Web Type
Hunting spider; does not build webs for capturing prey. It constructs small, silk, sack-like retreats under rocks, logs, or debris where it sleeps and molts during the day.
Eye Arrangement
Six eyes arranged in a tight semi-circle or oval cluster at the front of the cephalothorax, distinguishing it from most spiders which have eight eyes.
Leg Characteristics
The legs are relatively short, stout, and orange-red, matching the cephalothorax. They lack prominent banding and are used for steady walking rather than jumping.
Venom & Safety Information
Venom Information
Possesses venom used to subdue its prey. The venom is not considered medically significant to humans, though the large fangs can facilitate a painful mechanical bite.
Medical Significance
Low danger level. Bites are rare and usually occur when the spider is trapped against skin. Symptoms typical of a bee sting: localized pain, redness, and minor swelling. No systemic toxicity is associated with this species.
Safety Recommendations
Provide the spider a way out or relocate it using the 'cup and paper' method if found indoors. Wear gloves when gardening in leaf litter to avoid accidental defensive bites.
Habitat & Behavior
Habitat & Range
Globally distributed due to human transport. Found throughout North America, Europe, Australia, and parts of South America. Preferred habitats include moist areas under logs, rocks, leaf litter, and occasionally damp basements or crawlspaces.
Behavior & Temperament
A nocturnal, active wandering hunter. It is generally shy and will attempt to flee if disturbed. However, if handled roughly, it may bite defensively. It is a specialist feeder that specifically seeks out woodlice.
Diet & Prey
Primarily woodlice (sowbugs/pillbugs). Its elongated fangs are specifically evolved to reach around or pierce through the hard exoskeleton of terrestrial isopods.
Seasonal Activity
Active year-round in milder climates or inside buildings; outdoors, activity peaks in spring and summer months.
Description
An unmistakable hunter of the leaf litter, the Woodlouse Hunter is a specialized predator easily identified by its contrasting orange head and tan abdomen. While its large fangs may look intimidating, it is a beneficial garden predator that keeps isopod populations in check.
Key Features
Red-orange cephalothorax, cream abdomen, six eyes in a cluster, and exceptionally large, forward-pointing chelicerae.
Similar Species
Broad-faced Sac Spiders (Trachelas tranquillus) have similar colors but lack the oversized fangs and have eight eyes. Ground spiders (Gnaphosidae) lack the shiny, bi-colored look.
Life Cycle
Mating involves a complex ritual where the male must avoid the female's large fangs. Females lay eggs in a silk retreat and may provide limited protection until they hatch. Can live for 2-3 years.
Ecological Importance
Serves as a natural pest control agent in gardens and around homes, specializing in a prey source that few other predators exploit.
Conservation Status
Not evaluated by the IUCN, but considered common and widespread with no immediate threats.
Interesting Facts
The fangs of this spider are so long and powerful they can easily penetrate the tough, calcified shells of pillbugs that most other spiders cannot eat.
Photography Tips
Focus on the front of the spider to capture the eye arrangement and the large fangs, which are the primary diagnostic features. Diffused lighting helps reduce glare on its shiny cephalothorax.
Identified: 2026-07-21T05:31:09.552194