Knowing what types of spiders are found in your home is the best way to put you at ease when you see them or find spider webs. There are seven common types of house spiders you may encounter in and around your home:
1. American House Spiders
Less than an inch in size, American house spiders are brown with yellow (male) or orange (female) legs. They are the most common spider to be found in homes, though they build their nests in out-of-the-way places.
Are American house spiders poisonous? This web-building house spider’s bite is rare and not dangerous to humans.
Note: Although this question is commonly phrased this way, spiders may be venomous but aren’t poisonous. A venomous animal injects venom via a bite or sting; poisons are ingested, inhaled, or enter through your skin.
Basic Facts About American House Spiders:
Scientific name: Parasteatoda tepidariorum (syn. Achaeranea tepidariorum)
Coloring: Yellowish, tan, brown, or gray, with darker mottling or streaks.
Body: The abdomen is round, higher than long, usually with streaks on the side and V-shapes behind.
Legs: Often have a ring of dark color
Eyes: Eight eyes, with six facing forward and two on the side
Length (not including legs): 1/8 to 3/8 inch (females); 1/8 inch (males)
2. Wolf Spiders
Wolf spiders are brown or gray hairy creatures that grow half an inch to 2 inches, and prefer to hang out around windows, doorways, basements, garages, and attics. Rather than spin webs, these predators crawl around at night to hunt for food. Wolf spiders are timid and choose the flight over fight response when alarmed.
Are wolf spiders poisonous? They are not poisonous to humans, though because of their size, there can be pain at the site of the bite. Just ice it or spray it.
Basic Facts About Wolf Spiders:
Scientific name: Lycosidae spp.
Coloring: Gray, brown, black, or tan with dark brown or black body markings (especially stripes).
Body: Athletic spiders that run down their prey
Legs: Long
Eyes: Four large eyes in a row, with four smaller eyes below
Length (not including legs): from 1/2 inch to 2 inches.
3. Cellar Spiders
Cellar spiders have long legs and short bodies. They dwell inside cellars (obviously), crawl spaces, basements, and similar environments. These arachnids can construct massive spider webs and are harmful only to the insects upon which they prey. Also, they tend to cluster, so you might find a lot of massive webs down in that dark, dank cellar (hence the scary stories).
Are cellar spiders poisonous? It is the plot of many an overwrought story that a spider in the cellar kills with its bite, but in real life, their bite is not harmful to humans.
Basic Facts About Cellar Spiders:
Family: Pholcidae (cellar spiders) in order Araneae (spiders)
Coloring: Gray, tan, or whitish
Body: Peanut-shaped abdomen
Legs: Darkened joints that can make them appear to have knobby knees.
Eyes: 2 in the center of the face, and 3 on each side
Length (not including legs): 1/4 inch
4. Jumping Spiders
Jumping spiders are outdoor dwellers that mistakenly enter homes at times, but they are not a danger to humans. With very large eyes and flat faces, these gray- or black-hued creatures are about the size of a dime and don’t build webs.
Are jumping spiders poisonous? They do have venom in their bites, but very little, and apply it only when threatened. You likely will feel nothing. In worst-case scenarios, the bite of a jumping spider is less severe than a bee sting, but can cause a small welt (perhaps the size of a mosquito bite).
Basic Facts About Jumping Spiders:
Scientific name: Platycriptus undatus
Coloring: Grays, tans, and browns, with flecks of black, white, and red, coloring needed to hide in trees
Body: Flat, with an undulating pattern on the abdomen. Can appear to be fuzzy.
Legs: Move in a jerky gait.
Eyes: Eight eyes, two appearing to have goggles. Excellent vision.
Length (not including legs): to 5/8 inch (females); to 3/8 inch (males).
5. Hobo Spiders
Hobo spiders are often mistaken for other types because of their unremarkable looks. Not naturally house spiders, hobos cannot survive for long periods inside. Their bites are not life-threatening to humans, and they’ll only bite if they feel threatened.
Are hobo spiders poisonous? Their venom is not considered toxic to humans according to the Centers for Disease Control and Prevention. Their bite is painless to the point where people likely don’t realize that they have been bitten.
Basic Facts About Hobo Spiders:
Scientific name: Eratigena agrestis
Coloring: Brown with yellow markings
Body: Covered with fine, almost clear hairs that appear to be feathery, but can’t be seen without a hand lens or microscope
Legs: Long with black bands
Eyes: Eight, in two straight rows
Length (not including legs): Females are 3/8 – 5/8 inches long, males a little shorter.
6. Black Widow Spiders
Black widows strike fear in the hearts of many, and the red, hourglass-shaped markings of the females make them easy to spot. Even so, like other spiders, black widows want to avoid contact with humans and will bite only if directly threatened. If bitten, seek medical attention immediately, as a black widow’s bites can be dangerous.
Are black widow spiders poisonous? Their venom causes injury, and they have the fangs to deliver it. Black widow bites don’t kill, but do cause intense pain, especially in the abdomen and back, and muscle cramps. The symptoms can last for several days.
Basic Facts About Black Widow Spiders:
Scientific name: Latrodectus mactans and L. variolus
Coloring: Glossy, black, with red spots on the abdomen
Body: Hourglass shape
Legs: 8 legs, black, with bristles on their back legs used to cover their victims with silk
Eyes: Two rows of four. Eyesight is weak.
Length (not including legs): Females 3/8 of an inch. Males 1/4.
How to get rid of black widow spiders? See our article titled How to Get Rid of Black Widow Spiders.
7. Brown Recluse Spiders
Behind the brown recluse spider’s three pairs of eyes is a violin-shaped marking. Growing up to half an inch in length, this type of spider is found most often in properties near the Mississippi River Valley. Typically, bites from the brown recluse occur when people accidentally come into too-close contact with the spider. If a brown recluse spider bites you, seek prompt medical attention.
Are brown recluse spiders poisonous? A bite will be painless at first, but over two to eight hours the pain will hit. Symptoms include malaise, nausea, headache, and aches and pain in your muscles. A bite will at first have two small puncture wounds with some reddening around them. The outer edge will become redder and the pain will increase. At that point, get medical help.
Basic Facts About Brown Recluse Spiders:
Scientific name: Loxosceles reclusa
Coloring: Grayish, brown, and yellow.
Body: An oblong abdomen covered with gray hairs. Called “violin spider” because of a patch that looks like one on its head.
Legs: Long, slim.
Eyes: Three pairs of two eyes each, one in front and two on the sides.
Length (not including legs): 1/4 inch
How to get rid of brown recluse spiders? Read our article titled How to Get Rid of Brown Recluse Spiders.
House Spiders and Their Level of Danger
Spiders that are found in the home and their level of threat to humans:
Most Venomous
- Brown recluse spider (Loxosceles reclusa)
- Hobo spider (Eratigena agrestis)
- Black-footed yellow sac spider (Cheiracanthium inclusum)
- Long-legged sac spider (Cheiracanthium mildei)
- Western black widow spider (Latrodectus hesperus)
- Black house spider (Badumna insignis)
Less Venomous
- American house spider (Parasteatoda tepidariorum)
- False black widow spider (Steatoda grossa)
- Red house spider (Nesticodes rufipes)
- Long-bodied cellar spider (Pholcus phalangioides)
- Short-bodied cellar spider (Physocyclus globosus)
- Zebra jumping spider (Salticus scenicus)
- Carolina wolf spider (Hogna carolinensis)
- Rabid wolf spider (Rabidosa rabida)
- Southern house spider (Kukulcania hibernalis)
Source: Spider Identifications
What to Do to Keep Spiders Out of the House
Here are the strategies on how to get rid of spiders:
- Remove it: Rocks, wood piles, compost piles, and the like shouldn’t be kept by the home. They can provide shelter to a spider that one day wanders into the house.
- Caulk it: Seal cracks and crevices at the foundation.
- Fix it: Make sure screens have no holes or tears, and fit tight.
- Check it: Make sure doors fit properly. Look in the back of the closet for entrance points.
- Clean it: Keep crawl spaces and garages free of debris
- Think about it: Boxes and the like in basements, closets, and other dark storage areas.
- See to it: Always brush out or vacuum spider cobwebs to get rid of them.
- Spray it: There are people who swear by the home remedy of spraying peppermint oil about. The belief is that the spider’s increased sense of smell is overwhelmed by the peppermint, and that of all the possible things to spray, it smells the best to humans.
The Cost of Keeping Spiders Out
If you start to see spiders in your home, it might be time to call or click for an exterminator. Pest control pros will likely use a perimeter pesticide around the home to address the problem.
Cost: The cost of a spider exterminator can range between $150 and $300.
Spider Bites Can Be Dangerous
Bites from venomous spiders are serious enough to send people to emergency departments. According to a five-year study covering 6,457,534 admissions to emergency departments, 3% of animal-related injuries were from venomous spider bites:
| Venomous bite | Number | Percentage |
| Hornets/wasps/bees | 812,357 | 13 percent |
| Spiders | 164,667 | 3 percent |
| Snakes/lizards | 43,911 | 1 percent |
| Scorpions | 34,870 | 1 percent |
| Centipedes/millipedes | 6,135 | Less than 1 percent |
| Not specified | 40,037 | 1 percent |
[infogram id=”67877a41-a87c-42e7-b743-f4e6adeb1752″ prefix=”rgH” format=”interactive” title=”Bites From Venomous Animals”]
What to Do if You Are Bitten by a Spider
Experts offer the following advice if you are bitten by a spider:
- If you have reason to believe the bite came from a black widow or brown recluse spider, get medical attention right away.
- Swab the bite with an antiseptic to prevent infection.
- To reduce pain and swelling, put ice on the spot.
- If the pain or swelling increases, or other serious medical issues develop, get medical attention.
If you can, bring the spider to the physician’s office. It will help determine which antivenins to use.
Source: Trauma Surgery & Acute Care Open, the American Association for the Surgery of Trauma’s open access journal
Spiders Are Arachnids, Not Insects
Commonly mistaken for insects, spiders are actually arachnids. Arachnids are land-dwelling invertebrates that have two body segments, eight legs, and no wings nor antennae.
| Insects | Arachnids | |
| Body segments | Head, thorax, abdomen | Cephalothorax (head and thorax in one piece), abdomen |
| Legs | Six in three pairs | Eight in four pairs |
| Antennae | Two | None |
| Life cycle | Egg, pupa, larva, adult | Egg, immature and mature |
| Metamorphosis | Yes | No |
| Backbone | No | No |
| Exoskeleton | Yes | Yes |
| Wings | Many do | None do |
Of the 45,000 spider species living throughout the world, a little more than 1,000 of them live in the United States.
More beneficial than not, spiders are natural pest controllers that help keep living spaces free of insects, such as roaches, gnats, flies, earwigs, moths, and mosquitoes. Outdoors, they help keep bugs away from garden flowers and crops.
FAQ About Spiders
Spiders that live outside will die come winter, but spiders that live in your home survive year-round. House spiders may live up to a year or more in your home.
Spiders try to run, hide, or play dead when threatened. They will bite if you get your hand close enough. Something to remember: Spiders have poor vision, so they often don’t realize a threat, such as a hand reaching to it, until it is too late to do anything but attack.
Spiders feed on insects, often being the most important predator of them in your home or garden. Among the things they eat:
— Ants
— Aphids
— Bees
— Butterflies
— Crickets
— Flies
— Grasshoppers
— Mosquitoes
— Moths
— Yellow jackets
Not all spiders build webs, but they do all produce silk, which they use to:
— Build: Make nests
— Climb: In every direction
— Encase: They wrap their prey it
— Prevent: Attach themselves to prevent a fall
— Protect: Create egg sacs
When to Hire a Pest Control Pro
Now that you know what a few of the most common house spiders look like, remember that if you avoid contact and don’t surprise them, you really have nothing to worry about. Spiders may be scary, but they are usually harmless unless threatened. If you are worried, swat it.
However, should you have a venomous spider, such as a black widow or a brown recluse, or should you have a lot of spiders, you need to take action. Call a pest control pro near you or undertake a DIY project, because spiders won’t go away on their own.
Additional sources:
Main Image Credit: Jean and Fred Hort / Flickr / CC BY 2.0
