If you’ve stumbled upon a spider with a large, red abdomen while gardening or doing housework, you may have encountered the woodlouse spider. This fascinating arachnid gets its common name from its big, bulbous behind which can appear especially prominent
While the spider’s oversized rear may give it a comical appearance, there’s nothing funny about its powerful jaws and venomous bite. So it’s helpful to learn how to identify the woodlouse spider to admire safely from a distance.
Key Features of the Woodlouse Spider
The woodlouse spider (Dysdera crocata) has several distinctive features that set it apart:
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Large red abdomen – The spider’s oval-shaped abdomen is a reddish-orange to dark red hue. It dominates the body, protruding well over the smaller cephalothorax (head region).
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Smaller dark brown head – In contrast to the bright red abdomen, the cephalothorax is dark brown to blackish-brown and relatively petite.
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Long mouthparts – Also called chelicerae, the front appendages that contain the venom glands and fangs are quite prominent.
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Slender orange-red legs – The spider’s legs are thin with an orangey-red coloring and darker banding in parts
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Six eyes – The woodlouse spider has three sets of eyes, with the middle pair being the largest.
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No web spinning – Unlike most spiders, it does not spin webs to catch prey.
Habits and Habitats
The woodlouse spider doesn’t build webs to trap insects. Instead, it uses its formidable jaws to capture and kill its preferred prey – woodlice. This arachnid is perfectly designed for hunting armored bugs like pillbugs and sowbugs.
You’ll find the woodlouse spider lurking beneath rocks, leaf litter, rotting logs, and other debris where woodlice congregate. It hunts at night and takes refuge during the day in rolled up leaves or crevices lined with silk.
Woodlouse spiders live anywhere from forests to city parks where their woodlouse prey exists. They sometimes find their way into homes and basements unintentionally.
Bite Risks
Although non-aggressive, woodlouse spiders will bite in self-defense such as if accidentally squeezed or pressed against skin. Their large fangs can penetrate flesh and inject venom that contains neurotoxins.
Bites cause instant pain and swelling. The area may itch, throb, and turn red for several hours. Rarely, nausea, headache, and dizziness have occurred.
But compared to spiders like the black widow, woodlouse spider venom isn’t extremely potent. Bites should heal fully within a day or two. Only seek medical care if bite symptoms seem severe.
Is it a Woodlouse Spider?
To confirm you’ve spotted a woodlouse spider, look for these signature features:
- Plump red abdomen much wider than brown cephalothorax
- Long fang-like mouthparts for grabbing woodlice prey
- Thin orangey-red legs with banding
- Six small eyes with two middle eyes being largest
- Lack of a web – these spiders hunt instead
A woodlouse spider’s massive abdomen for egg production gives it a very distinctive silhouette. Just be sure to admire its rotund behind from a safe distance!
Woodlouse Spider Behaviors, Threats, or Dangers
Woodlouse spiders in Chicago are reported to mate in spring, with eggs being deposited shortly after. The courtship of these spiders is typically aggressive and mates risk injury from each other’s large fangs. Silk is not used for prey capture but is used to construct retreats when molting and for egg-laying. The eggs hang from silken threads in the retreat, and up to 70 eggs can be put down at once.
Unlike most spiders, the female woodlouse spider is believed to take care of her offspring. Spiderlings that have just hatched stay with their mother at first, living in her retreat for a while before moving out on their own. Spiders reach maturity at around 18 months of age and may live up to three years.
In August 2018, a Facebook post with a picture of the woodlouse spider went viral. It was about a new spider whose bite could kill you in the U.S. S. , however, these claims are false. The truth is that the woodlouse spider may be able to bite if it is touched, but its poison does not pose any threat to humans. Getting rid of the woodlouse spider in your home may require professional assistance, Anderson Pest Solutions can help!.
Woodlouse Spiders in Illinois and Indiana
The woodlouse spider, Dysdera crocata, is a night-hunter that lives in gardens and homes from New England to Georgia, as well as in the Midwest (Illinois and Indiana), and the Pacific Northwest. It is also commonly encountered in England, northern Europe, and Australia. Dysdera crocata gets its name from its prey, woodlice, also known as isopods, pillbugs, roly-poly bugs, and sowbugs.
The woodlouse spider is most commonly found around damp areas close to their food source, woodlice. They like rotting plants and wood, and you can usually find them in basements, under stones and boards, around doors and windows, and other places where there is rotting wood. People who garden like having these spiders around because they help get rid of woodlice, which are very bad for plants.
Woodlouse spiders hunt at night without the use of a web. During the day, this spider hides in a silken cave it built under rocks, logs, wood, or other debris where isopods live. In homes, this spider is generally found in basements and areas with high humidity.
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FAQ
Is woodlouse spider poisonous?
Are woodlouse spiders rare?
Is the red house spider poisonous?
Is red Stripe spider Poisonous?
What spiders have red markings?
Cobweb Spiders (Theridiidae) Widow Spiders (Latrodectus) – The black widow is probably the most infamous spider with red markings. There are 5 species found in the USA & Canada. All 5 species can be black & red in color though the brown widow is usually a light brown. The red hourglass (sometimes orange) is found on the ventral side of the abdomen.
What is a red backed jumping spider?
Phidippus johnsoni, the red-backed jumping spider or Johnson jumping spider, is one of the largest and most commonly encountered jumping spiders of western North America. It is not to be confused with the unrelated and highly venomous redback spider (Latrodectus hasselti). Adults tend to be about a centimeter in length.
What does a red-bellied jumping spider look like?
The Red-bellied Jumping spider gets its name from the coloring of its underbelly. This spider is known for being black on top. An orange-red abdomen is characteristic as are red front legs. The spider has a variable size as it grows from 7 to 12 mm in the case of females. Males are almost twice as small with an average size of 5mm.
What does a fighting Spider look like?
Fighting spiders are known for the vivid colors they come in. The red morph has orange undertones making it one of the jumping spiders easy to spot. Its color isn’t uniform, however. The cephalothorax has dark red coloring and a brown mark on the head. The lighter red coloring is specific to the abdomen.