The woodlouse spider stands out in your garden or basement because of its reddish body and large fangs. You can recognize this spider by its unique appearance and its preference for hunting woodlice instead of spinning webs. With its strong jaws, it feeds almost exclusively on woodlice, making it a specialized predator.
You might spot woodlouse spiders under rocks, among leaf litter, or in dark corners of your home. Their nocturnal habits and striking looks often catch the attention of curious observers.
Learning about how this spider lives and interacts with its environment helps you understand its role in controlling woodlouse populations.
You can recognize a woodlouse spider by its distinctive body structure, preferred habitats, and specialized behaviors. Understanding these aspects will help you identify this spider and anticipate where you are likely to encounter it.
The woodlouse spider (Dysdera crocata) has a striking appearance that sets it apart from other spiders. Its body is usually 11–15 mm long, with females larger than males. One of the most noticeable features is its large, powerful chelicerae (fangs), which are reddish-brown and visibly firm.
The cephalothorax is glossy red to orange, while the abdomen tends to be pale gray or beige. You won’t find markings or patterns on its smooth abdomen. This spider has six eyes arranged in a semicircle, rather than the typical eight.
| Feature | Description |
| Body Length | 11–15 mm |
| Chelicerae (fangs) | Large, reddish, prominent |
| Abdomen Color | Pale gray, smooth, unmarked |
| Eyes | Six, arranged in a semicircle |
The woodlouse spider’s legs are pale yellow or orange. Its robust front legs help it capture prey.
Woodlouse spiders favor damp, sheltered locations in gardens and homes. You’ll often find them under logs, stones, leaf litter, or compost heaps. These spots are usually rich in woodlice, their primary prey.
Inside your home, they may take shelter in basements, under flowerpots, or behind outdoor structures. They prefer areas with high humidity and readily available cover, as they do not spin webs for catching food. Instead, they require environments where they can roam and hunt at night.
Their distribution covers much of Europe, North America, and Australia, adapting well to both urban and rural settings. Look for them where woodlice are abundant, as their presence often indicates a rich food source.
The woodlouse spider does not construct webs for hunting. Instead, it is a nocturnal predator, emerging at night to actively stalk and overpower woodlice using its specialized fangs. Its large chelicerae are adapted to penetrate the tough exoskeleton of woodlice.
This spider is solitary, avoiding unnecessary contact with other spiders or animals. When disturbed, the woodlouse spider may exhibit defensive behavior by rearing up or attempting to bite its attacker. Their bite can cause mild pain and redness in humans, but it is not medically significant.
During the day, you will find them hiding in silken retreats they construct in crevices or beneath debris. Their hunting strategy relies on stealth and the element of surprise, making them efficient and adaptable predators within their environment.
Woodlouse spiders are active, nocturnal hunters with a highly specialized diet and unique reproductive habits. Their presence in various habitats influences local invertebrate populations and contributes to ecological balance.
You will find that the woodlouse spider (Dysdera crocata) primarily preys on woodlice, also known as pill bugs or sowbugs. This dietary specialization sets them apart from many other ground-dwelling spiders. Their large chelicerae, or jaws, allow them to pierce the tough exoskeleton of their prey with ease.
The hunting process is direct and involves active pursuit rather than waiting in webs. They inject venom to immobilize woodlice quickly, then consume the softened insides. While woodlice are their primary source of food, woodlouse spiders can occasionally eat other small invertebrates when their preferred prey is scarce.
You might observe these spiders searching under rocks, logs, and garden debris—places where woodlice congregate. Their ability to hunt in close quarters makes them efficient predators within their habitat.
Typical Prey List:
Reproduction in woodlouse spiders occurs mainly during the warmer months. Males search for females at night, often putting themselves at risk from predators during this activity. Once a mate is found, courtship involves a careful approach to avoid aggression, as females can be cannibalistic.
After mating, the female constructs a silken sac where she lays her eggs, typically producing one to two egg sacs per breeding season. Each sac may contain 30 to 50 eggs. The sac is hidden under stones or in crevices to protect it from predators and moisture loss.
Spiderlings hatch after a few weeks and remain with the mother for a short period before dispersing to find their territories. Maturity is usually reached within a year, and adults may live up to two years in suitable conditions.
As a predator of woodlice, the woodlouse spider plays a significant role in controlling woodlouse populations, which can affect the decomposition rates of organic matter. By regulating their prey, you indirectly help maintain a balanced soil ecosystem, as woodlice are known for their role in breaking down dead plant material.
The presence of woodlouse spiders contributes to natural pest management in gardens and compost heaps. While they have few natural predators themselves, birds, centipedes, and larger spiders sometimes prey upon them.
Through their hunting habits and interactions with other species, these spiders influence both prey populations and the broader invertebrate community. Their ecological role emphasizes the importance of predator-prey dynamics in maintaining healthy garden and woodland environments.
If you have noticed reddish-brown spiders with large jaws inside your home, you may be dealing with a woodlouse spider. These spiders are often found in basements, bathrooms, and damp, dark corners where woodlice—their primary prey—are common.
Signs you may have a woodlouse spider problem:
Woodlouse spiders are not considered dangerous to humans, but their bite can be painful if handled carelessly. Their presence indicates that woodlice are also thriving in your space, as these spiders follow their food source.
| Woodlouse Spider Features | Description |
| Color | Reddish brown body, pale abdomen |
| Size | About 10-15 mm |
| Fangs | Large, forward-pointing |
| Typical Habitat | Damp, sheltered environments |
To keep woodlouse spiders away, remove debris and regularly clean potential hiding spots. Sealing cracks and fixing moisture issues can help discourage both woodlice and their predators.
If you’re having trouble with woodlouse spiders or other pests, contact Critter Stop for a free inspection at (214) 234-2616. Critter Stop is renowned for its exceptional, reliable service, boasting outstanding customer reviews online due to its thorough work and commitment to humane solutions.
You may encounter the woodlouse spider in your home or garden. Its appearance, bite, and behavior often raise questions about identification and handling.
A woodlouse spider usually has a reddish-brown cephalothorax and legs, with a pale or yellow-beige abdomen. Its prominent, forward-pointing fangs and large size set it apart from many other spiders found in similar environments. You will notice it has six eyes arranged in a compact cluster. This spider’s glossy surface and robust body are also identifying traits.
The woodlouse spider can bite if threatened, but its bite is not medically significant for most people. You may experience localized pain, redness, or swelling, which typically resolves on its own without the need for treatment. Severe reactions are rare, but if you experience unusual symptoms, consult a medical professional.
You can occasionally find woodlouse spiders indoors, especially in damp areas like basements or bathrooms. They enter homes in search of prey or shelter. Deal with them by safely relocating the spider outdoors using a container and paper, or by sealing cracks and gaps where they may enter your home.
Adult woodlouse spiders generally range from 11 to 15 millimeters in body length. Females tend to be slightly larger than males. Including the legs, their full span can appear even larger, making them one of the more noticeable spiders in their habitat.
To differentiate, look for the combination of red-brown legs and cephalothorax, pale oval abdomen, and six eyes. Many common spiders have eight eyes, making the eye pattern a key distinguishing feature. Also, woodlouse spiders have distinctly large fangs and lack the web structures that other species build.
Woodlouse spiders are found in Europe, North Africa, and have been introduced to North and South America, as well as Australia and New Zealand. They thrive in temperate zones with abundant woodlice, their preferred prey. You typically encounter them under stones, logs, or garden debris, and sometimes inside human dwellings near damp areas.
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