The woodlouse spider, scientifically known as Dysdera crocata, is a species frequently encountered by humans. This arachnid is commonly referred to as the woodlouse hunter, sowbug killer, or pillbug hunter, reflecting its primary diet. A common question arises regarding the potential danger of its venom to humans, particularly given its distinctive appearance and large fangs. While it possesses venom, its impact on human health is generally not considered significant.
Understanding Woodlouse Spider Venom
Woodlouse spiders primarily use venom to subdue prey like woodlice. This venom effectively pierces their tough exoskeletons, allowing the spider to immobilize and consume them.
The discomfort from a woodlouse spider bite is largely due to the mechanical puncture from its disproportionately large fangs rather than the venom itself. Its low toxicity means serious complications in humans are rare. Bites generally cause mild, temporary effects, often subsiding without significant medical intervention.
Recognizing a Woodlouse Spider
Woodlouse spiders typically have a reddish-brown cephalothorax (head and thorax region) and legs. Their abdomen is usually a greyish-white or creamy color, often appearing shiny. A prominent feature is their large, forward-pointing chelicerae, or jaws.
Adult females generally measure about half an inch in length, while males are slightly smaller, around a quarter to a third of an inch. Unlike many other spider species, woodlouse spiders have six eyes arranged in a tight group. They are nocturnal hunters and do not spin webs for catching prey, instead actively seeking out woodlice in damp, dark environments. These spiders are commonly found outdoors under logs, rocks, leaf litter, and in woodpiles, but can also enter homes, particularly basements or other moist areas.
If Bitten by a Woodlouse Spider
If bitten by a woodlouse spider, individuals often experience a sharp, initial pain due to the mechanical penetration of the large fangs. Common reactions include localized redness, itching, or minor swelling at the affected site. This discomfort usually subsides within a short period, often less than an hour.
For first aid, cleaning the bite wound with mild soap and water is recommended. Applying a cool compress or ice pack to the area for about 15 minutes each hour can help reduce pain and swelling. Over-the-counter pain relievers or antihistamines may be used for discomfort or itching. Medical attention might be necessary if symptoms worsen, if there are signs of infection such as spreading redness or pus, or in the rare event of an allergic reaction.
Preventing Woodlouse Spider Encounters
To minimize woodlouse spider encounters, particularly indoors, seal cracks and gaps in the foundation and around windows and doors to prevent their entry. Using caulk for smaller openings and weatherstripping for gaps around doors and windows creates effective barriers.
Reducing clutter in areas like basements, garages, and storage spaces removes potential hiding spots for these spiders. Managing moisture levels indoors by fixing leaks and using dehumidifiers in damp areas can make the environment less attractive to them, as they prefer high humidity. Additionally, clearing away woodpiles, leaf litter, and other debris near the home’s exterior can reduce their outdoor habitats and discourage them from seeking shelter inside.