Cellar Spider: All You Need to Know – Quick & Easy Facts

Cellar spiders are a fascinating species commonly found in dark, secluded areas of homes and buildings. Although they may look intimidating due to their long legs and distinctive appearance, these spiders are actually quite harmless. In this article, we’ll explore everything you need to know about cellar spiders, from their habits to their benefits.

There are two main types of cellar spiders: long-bodied and short-bodied. The female long-bodied cellar spider measures approximately 1/4-5/16 inch long with legs extending another 2 inches, while the female short-bodied cellar spider has a 1/16 inch long body with legs extending about 5/16 inch source. Both types of cellar spiders prefer dark and moist environments, making them common inhabitants of basements, crawlspaces, and cellars.

Some interesting characteristics of cellar spiders include:

  • Long, delicate legs
  • Gray, tan, or whitish color
  • Small body size
  • Remarkable habit of “vibrating” or bouncing in their webs when alarmed source.

In the next sections, we will dive deeper into the world of cellar spiders, exploring their behaviors, life cycle, and the potential benefits they bring to our homes.

What Is a Cellar Spider?

Species and Classification

Cellar spiders belong to the family Pholcidae and are often referred to as “daddy longlegs.” However, it is important to note that there are two other unrelated arachnids commonly called daddy longlegs: harvestmen and craneflies.

There are two main types of cellar spiders:

  • Long-bodied cellar spiders
  • Short-bodied cellar spiders

Appearance

Cellar spiders have a distinct appearance, with their most noticeable features being their long, slender legs. Here is a comparison of the two types of cellar spiders:

Feature Long-bodied Cellar Spider Short-bodied Cellar Spider
Body length 1/4-5/16 inch1 1/16 inch1
Leg length 2 inches1 5/16 inch1
Color Pale gray to light tan2 Similar to long-bodied spiders
Eyes 8 eyes, arranged in 2 rows1 Similar to long-bodied spiders

Cellar spiders build loose, irregular webs in corners near the ceiling or floor2. They are not known to be harmful and can help control other pests by feeding on insects in and around your home.

Anatomy of a Cellar Spider

Body and Legs

The body of a typical cellar spider is quite small, while the legs are extremely long and thin, giving them a wispy appearance. To provide more detail:

  • Female long-bodied cellar spiders: body is approximately 1/4-5/16 inch long, and legs extend another 2 inches.
  • Female short-bodied cellar spiders: body is around 1/16 inch long, and legs extend about 5/16 inch.

The tarsi, or “feet,” of cellar spiders are flexible, adding to the fragile impression they give.

Abdomen and Color

Cellar spiders have a tubular abdomen that is gray, tan, or whitish in color. Their small body size and neutral coloration help them to blend into their environment, making them inconspicuous.

Venom and Fangs

While cellar spiders are venomous, their venom is not considered harmful to humans. Their fangs are very small, and they typically use their long legs to cast silk onto their prey, immobilizing it from a safe distance.

To summarize:

  • Cellar spiders have a small body and long, thin legs.
  • Their tubular abdomen can be gray, tan, or whitish in color.
  • They are venomous but not harmful to humans.
Feature Cellar Spiders
Body size Small
Leg length Extremely long
Abdomen shape Tubular
Color Gray, tan, or whitish
Venom Present but not harmful to humans

Habitats and Distribution

Typical Areas

Cellar spiders are commonly found in:

  • Cellars: As their name suggests, these spiders are often spotted in cellars.
  • Basements: They prefer damp, dark environments like basements.
  • Crawl spaces: Crawl spaces and other undisturbed areas in the house are perfect habitats for these spiders.
  • Attics: Some species of cellar spiders may also be seen in attics or other moist areas of the house.
  • Garages: They can be found in garages, especially near crevices.
  • Warehouses: These spiders sometimes make their homes in warehouses.

They tend to build irregular webs to catch their prey.

Range and Distribution

Cellar spiders have a wide geographic distribution. They can be found in:

  • Buildings: They are commonly spotted in various types of buildings.
  • Caves: Some species may also thrive in caves and other damp areas.
  • Spider-infested areas: In areas where spider infestations are common, cellar spiders may coexist with other species like the black widow.
Area Presence of Cellar Spiders
Cellars Yes
Basements Yes
Crawl spaces Yes
Attics Yes
Garages Yes
Warehouses Yes
Caves Yes (some species)
Spider-infested areas Yes (sometimes)

Overall, cellar spiders are widespread and can be found in many different environments where moisture and undisturbed spaces are present.

Reproduction and Life Cycle

Mating Behavior

Cellar spiders exhibit unique mating rituals, where males often use their long legs to tap and vibrate the female’s web. This behavior is crucial in attracting the attention of the female cellar spider.

Egg Sacs

Female long-bodied cellar spiders can produce about three egg sacs over their lifetime 1, each containing 13-60 eggs. They hold the egg sacs using their jaws and legs, ensuring the safety and protection of their offspring.

Spiderlings

Upon hatching:

  • Spiderlings are tiny versions of adult cellar spiders.
  • They go through several molts before reaching adulthood.

Diet and Hunting Techniques

Common Prey

Cellar spiders, being part of the Pholcidae family, mainly feed on insects and other arachnids. Some examples of their prey include:

  • Flies
  • Mosquitoes
  • Ants
  • Small moths

These spiders play a vital role in natural pest control, as they help reduce the population of common pests found in homes and gardens.

Cobwebs and Loose Webs

Cellar spiders create silk webs to catch their prey. Their webs, often found in cellars, corners, and dark spaces, have some unique features:

  • Irregular shape
  • Loose structure
  • Resembling cobwebs

When comparing cellar spiders to cobweb spiders, their webs have some differences:

Feature Cellar Spider Webs Cobweb Spider Webs
Shape Irregular Irregular
Structure Loose Dense
Placement Ceilings and corners Corners and edges

Once prey is caught in their web, cellar spiders use their long legs to quickly reach and immobilize their victims with venom. The spiders then consume their prey, keeping the environment cleaner and reducing the number of pest insects.

In conclusion, cellar spiders are effective hunters that utilize their webs and venom to capture a variety of insects, making them an excellent form of natural pest control. Their webs, though somewhat similar to cobwebs, have distinct differences in structure and placement.

Dealing with Cellar Spiders

Prevention Measures

To protect your home from cellar spiders, consider implementing the following preventive measures:

  • Regularly clean and vacuum your home, focusing on corners, crevices, and dark spaces where spiders like to hide.
  • Use a dehumidifier to reduce humidity levels in damp areas such as basements and crawlspaces.
  • Seal any cracks or gaps in your home’s exterior with weatherstripping and caulk to prevent spiders from entering.
  • Install door sweeps on exterior doors to keep spiders out.
  • Replace standard outdoor lights with yellow light bulbs, which attract fewer insects and subsequently fewer spiders looking for food.

How to Remove Cellar Spiders

If you already have cellar spiders in your home, here are some methods for removing them:

  • Use a vacuum cleaner with a hose attachment to remove spiders and their webs from corners and crevices.
  • Sweep up spiders and their webs using a long-handled broom, then dispose of them outside.
  • For more severe infestations, consider using an insecticide specifically labeled for spiders. Be sure to read and follow the product label instructions for safe and effective spider control.
Method Pros Cons
Vacuuming Quick and easy; no chemicals needed May not reach all spiders and webs
Broom Chemical-free; can reach high places May require more effort to remove all
Insecticide Effective for severe infestations Chemicals may pose risks if misused

Remember, cellar spiders are generally harmless and may even help control other insect populations in your home. However, if you prefer to keep them out or remove them from your living space, these prevention and removal tips can help.

Misconceptions and Myths

One common myth about cellar spiders is that they are dangerous or harmful creatures. In reality, these spiders are harmless and are not known to bite people. Their appearance might be unsettling to some, but there is no need to fear them.

It is also worth mentioning the misconception that cellar spiders are “daddy long legs” spiders. Although they have similar appearances, cellar spiders and daddy long legs are actually distinct species. Cellar spiders belong to the family Pholcidae, while daddy long legs belong to the family Pholcidae or the order Opiliones.

Here is a comparison table outlining their differences:

Feature Cellar Spiders Daddy Long Legs
Appearance Long, delicate legs Slightly shorter legs
Habitat Basements, cellars, dark corners Gardens, grasslands
Harm to Humans Harmless, not known to bite Also harmless

Another myth about cellar spiders is that their vibrating behavior is an aggressive act. In reality, this unique characteristic of vibrating spiders when disturbed is a defensive technique. It helps them avoid being detected by potential predators or threats, as the rapid movement creates a blurry visual effect.

Lastly, it’s essential to debunk the killer spider myth. Some rumours suggest that cellar spiders are deadly or can kill black widow spiders. In truth, cellar spiders are not killers and do not pose any serious threat to humans or other spiders. They may prey on other insects, but they are not venomous like black widow spiders.

To sum up, cellar spiders are:

  • Harmless and not known to bite
  • Often confused with daddy long legs
  • Vibrating spiders for defense, not aggression
  • Not killer spiders as myths suggest
  • Distinct from black widow spiders

Footnotes

  1. Clemson University – Cellar Spiders 2 3 4 5 6

  2. University of Minnesota Extension – Spiders 2

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Can this be a Green Cellar Spider???

 

Subject: can Pholcus phalangioides change its coloration to match its environment?
Location: Jefferson County, Illinois
November 28, 2014 6:35 pm
Hello!
I am extremely nature friendly and generally let spiders have the run of my house within reason. This year I had a bumper crop of cellar spiders and although I find them interesting, their webs can get to be an issue and I am constantly tidying up after them. Not long ago I noticed a silk-wrapped stilt bug hanging down by the kitchen table and as I bent down to brush it away I noticed something luminous and bright green on it. Upon closer inspection I was fascinated to find that I had discovered both dinner and diner and , most importantly, the diner appeared to be one of “my” cellar spiders that had somehow turned a strange shade of green I’ve never seen before! All of the cellar spiders I have seen here are various shades of tan, brown, or even a light translucent grey, but never this bright green. Even stranger, the spider has been residing among a collection of volleyball trophies on my tabletop and the background color in these trophies is the exact shade of green. Initially I thought well yes, if you are looking at the spider at the right time of day with the right light, the abdomen is likely reflecting the green from the trophies. But the cephalothorax is the expected color, as are the legs, and even in dim light or shadow you can still see the bright green. So I am puzzled and intrigued.
I am aware that many creatures can manipulate their background color but is there anything known about cellar spiders having this ability? If she ( I say she, I can’t see any pedipalps without disturbing the spider) weren’t so fragile I would put her in a different location and watch for changes but I don’t want to harm her.
Anyway I hope I can load the pictures correctly so you can have a look-see.
thank you !
WT
Signature: Wendy T.

Green Cellar Spider or something else???
Green Cellar Spider or something else???

Dear Wendy,
This sure looks like a Cellar Spider, but the green coloration is certainly unusual.  We are going to post your images and attempt to research this more thoroughly before we weigh in with an opinion, and hopefully one of our readers can either provide a definitive identification or comment on the coloration.

Possibly Green Cellar Spider
Possibly Green Cellar Spider

Letter 2 – Cellar Spider with Clutch of Eggs from UK

 

Subject: what are these spiders
Location: widnes Cheshire uk
September 12, 2015 6:32 pm
hello
I’m wondering what types of spiders these are I live in the UK, Cheshire, widnes
I would be very grateful for your input
Signature: jade

Cellar Spider from the UK
Cellar Spider from the UK

Dear Jade,
One of your images is a Cellar Spider,
Pholcus phalangioides, with a clutch of eggs.  You can read more about Cellar Spiders on British Spiders where it states:  “The species is widespread in England and Wales, and although it is absent from much of northern Britain, there are records as far north as Shetland” and “It particularly favours undisturbed parts of houses such as cellars and bathrooms where it can establish large colonies beneath baths and shower-trays. As it makes an untidy web in the corners of ceilings it is not usually permitted a permanent abode in such conspicuous situations but it has no difficulty in surviving where there is a limited tolerance by house owners. It is one of the few species of spider that has acquired a vernacular name, being known as the daddy long legs spider because of its long legs.”  It is a harmless species.  Your other image is too blurry for identification.

Letter 3 – Lampshade Weaver and Long Bodied Cellar Spider with Brood

 

A whole unknown type of arachno-family
Location: McCreary County, Kentucky
November 5, 2011 5:48 pm
Hello. I am very curious as to what kind of spider these may be. While I am arachnophobic, I am also quite adventurous, and thoroughly curious.
While on vacation this past August in Southeastern Kentucky, I came across this ”little” guy in the Daniel Boone National Forrest. He was hanging around the underside of a damp rock face along with several other fairly common arachnids like Wolf and furrow spiders.
I am under the impression that it is likely that this is a male and female coupling since what I think is a freshly hatched bunch of young are clinging to the smaller of the two.
Unfortunately I could not figure out a way to include a visual size reference in the image. However, I noted that the smaller of the two is roughly the same size as a common cellar spider.
I could not tell if the web was orb or cob-web like.
I lived in this area for 6 years and never saw, or at least noticed, anything quite like this.
I have several questions.
What kind of spider or spiders are these?
Are they male and female?
Are the newly-born eating or riding the smaller critter?
Thanks for any information you may have!
Signature: arsinal Apocalypse

Lampshade Weaver and Long Bodied Cellar Spider with Brood

Dear arsinal Apocalypse,
We are relatively confident that the smaller spider with the brood is a Long Bodied Cellar Spider,
Pholcus phalangioides, and we found a photo depicting similar maternal care on BugGuide.  The female Long Bodied Cellar Spider carries the eggs about until they hatch.  Here is another photo series from BugGuide showing the eggs in the process of hatching.  We believe the larger spider is a different species.  We hope to get a more definitive answer eventually.

Long Bodied Cellar Spider with Brood

Daniel:
Would really, really help to know the geographic location where the spiders were found….
That said, it looks like maybe a male “lampshade weaver,” genus Hypochilus, family Hypochilidae.  They only occur in the Appalachian mountains, parts of the southern Rocky Mountains, and parts of the Sierras(?) in North America.
Looking forward to learning more.  This might be of interest for Bugguide.net if it was not found in the Smoky Mountains.
Eric

Male Lampshade Weaver

This picture was taken at the Split Bow Arch in McCreary County, Kentucky in the Appalachian area.
I thought the other looked like a cellar spider, as my size reference may have indicated, but with the close proximity of the two, my distance and my lack of knowledge, I had to wonder.
The image seems fairly spot on to me, specifically the dark dot like marking on the back! Thanks for answering my question and IDing my bugs! You guys are Awesome!
The ‘cave spider’ name explains it all. I’ve done hiking and camping in the area, but I tend to stay away from the caves and rock shelters for obvious reasons. I can handle being within a certain distance of 8 legged critters as long as they don’t move. The second they move, I’m outta dodge! Hence my interest to learn as much as I can about them and (hopefully) conquer whatever is stuck in my head that they are *after* me 😛
The worst were always the 6 spot fishing spiders. I don’t know that they were *after* me persay, but they certainly weren’t too shy to chase after a human invading their space, even if it was my room 😛

Letter 4 – Long Bodied Cellar Spider and Egg Sac

 

cobweb spider with egg sack
We have these in our basement shower all the time but this is the first time I’ve seen one with an egg sack. I didn’t see a picture of a cobweb spider with an egg sack as good as this one on your web site and thought you might like it. Hope you enjoy it.
Becky

Hi Becky,
We will happily post your image of a Cobweb Spider, Pholcus phalangioides, and her Egg Sac. We use the common name Cobweb Spider after Hogue in his wonderful book “Insects of the Los Angeles Basin, but BugGuide calls this the Long Bodied Cellar Spider.

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Can this be a Green Cellar Spider???

 

Subject: can Pholcus phalangioides change its coloration to match its environment?
Location: Jefferson County, Illinois
November 28, 2014 6:35 pm
Hello!
I am extremely nature friendly and generally let spiders have the run of my house within reason. This year I had a bumper crop of cellar spiders and although I find them interesting, their webs can get to be an issue and I am constantly tidying up after them. Not long ago I noticed a silk-wrapped stilt bug hanging down by the kitchen table and as I bent down to brush it away I noticed something luminous and bright green on it. Upon closer inspection I was fascinated to find that I had discovered both dinner and diner and , most importantly, the diner appeared to be one of “my” cellar spiders that had somehow turned a strange shade of green I’ve never seen before! All of the cellar spiders I have seen here are various shades of tan, brown, or even a light translucent grey, but never this bright green. Even stranger, the spider has been residing among a collection of volleyball trophies on my tabletop and the background color in these trophies is the exact shade of green. Initially I thought well yes, if you are looking at the spider at the right time of day with the right light, the abdomen is likely reflecting the green from the trophies. But the cephalothorax is the expected color, as are the legs, and even in dim light or shadow you can still see the bright green. So I am puzzled and intrigued.
I am aware that many creatures can manipulate their background color but is there anything known about cellar spiders having this ability? If she ( I say she, I can’t see any pedipalps without disturbing the spider) weren’t so fragile I would put her in a different location and watch for changes but I don’t want to harm her.
Anyway I hope I can load the pictures correctly so you can have a look-see.
thank you !
WT
Signature: Wendy T.

Green Cellar Spider or something else???
Green Cellar Spider or something else???

Dear Wendy,
This sure looks like a Cellar Spider, but the green coloration is certainly unusual.  We are going to post your images and attempt to research this more thoroughly before we weigh in with an opinion, and hopefully one of our readers can either provide a definitive identification or comment on the coloration.

Possibly Green Cellar Spider
Possibly Green Cellar Spider

Letter 2 – Cellar Spider with Clutch of Eggs from UK

 

Subject: what are these spiders
Location: widnes Cheshire uk
September 12, 2015 6:32 pm
hello
I’m wondering what types of spiders these are I live in the UK, Cheshire, widnes
I would be very grateful for your input
Signature: jade

Cellar Spider from the UK
Cellar Spider from the UK

Dear Jade,
One of your images is a Cellar Spider,
Pholcus phalangioides, with a clutch of eggs.  You can read more about Cellar Spiders on British Spiders where it states:  “The species is widespread in England and Wales, and although it is absent from much of northern Britain, there are records as far north as Shetland” and “It particularly favours undisturbed parts of houses such as cellars and bathrooms where it can establish large colonies beneath baths and shower-trays. As it makes an untidy web in the corners of ceilings it is not usually permitted a permanent abode in such conspicuous situations but it has no difficulty in surviving where there is a limited tolerance by house owners. It is one of the few species of spider that has acquired a vernacular name, being known as the daddy long legs spider because of its long legs.”  It is a harmless species.  Your other image is too blurry for identification.

Letter 3 – Lampshade Weaver and Long Bodied Cellar Spider with Brood

 

A whole unknown type of arachno-family
Location: McCreary County, Kentucky
November 5, 2011 5:48 pm
Hello. I am very curious as to what kind of spider these may be. While I am arachnophobic, I am also quite adventurous, and thoroughly curious.
While on vacation this past August in Southeastern Kentucky, I came across this ”little” guy in the Daniel Boone National Forrest. He was hanging around the underside of a damp rock face along with several other fairly common arachnids like Wolf and furrow spiders.
I am under the impression that it is likely that this is a male and female coupling since what I think is a freshly hatched bunch of young are clinging to the smaller of the two.
Unfortunately I could not figure out a way to include a visual size reference in the image. However, I noted that the smaller of the two is roughly the same size as a common cellar spider.
I could not tell if the web was orb or cob-web like.
I lived in this area for 6 years and never saw, or at least noticed, anything quite like this.
I have several questions.
What kind of spider or spiders are these?
Are they male and female?
Are the newly-born eating or riding the smaller critter?
Thanks for any information you may have!
Signature: arsinal Apocalypse

Lampshade Weaver and Long Bodied Cellar Spider with Brood

Dear arsinal Apocalypse,
We are relatively confident that the smaller spider with the brood is a Long Bodied Cellar Spider,
Pholcus phalangioides, and we found a photo depicting similar maternal care on BugGuide.  The female Long Bodied Cellar Spider carries the eggs about until they hatch.  Here is another photo series from BugGuide showing the eggs in the process of hatching.  We believe the larger spider is a different species.  We hope to get a more definitive answer eventually.

Long Bodied Cellar Spider with Brood

Daniel:
Would really, really help to know the geographic location where the spiders were found….
That said, it looks like maybe a male “lampshade weaver,” genus Hypochilus, family Hypochilidae.  They only occur in the Appalachian mountains, parts of the southern Rocky Mountains, and parts of the Sierras(?) in North America.
Looking forward to learning more.  This might be of interest for Bugguide.net if it was not found in the Smoky Mountains.
Eric

Male Lampshade Weaver

This picture was taken at the Split Bow Arch in McCreary County, Kentucky in the Appalachian area.
I thought the other looked like a cellar spider, as my size reference may have indicated, but with the close proximity of the two, my distance and my lack of knowledge, I had to wonder.
The image seems fairly spot on to me, specifically the dark dot like marking on the back! Thanks for answering my question and IDing my bugs! You guys are Awesome!
The ‘cave spider’ name explains it all. I’ve done hiking and camping in the area, but I tend to stay away from the caves and rock shelters for obvious reasons. I can handle being within a certain distance of 8 legged critters as long as they don’t move. The second they move, I’m outta dodge! Hence my interest to learn as much as I can about them and (hopefully) conquer whatever is stuck in my head that they are *after* me 😛
The worst were always the 6 spot fishing spiders. I don’t know that they were *after* me persay, but they certainly weren’t too shy to chase after a human invading their space, even if it was my room 😛

Letter 4 – Long Bodied Cellar Spider and Egg Sac

 

cobweb spider with egg sack
We have these in our basement shower all the time but this is the first time I’ve seen one with an egg sack. I didn’t see a picture of a cobweb spider with an egg sack as good as this one on your web site and thought you might like it. Hope you enjoy it.
Becky

Hi Becky,
We will happily post your image of a Cobweb Spider, Pholcus phalangioides, and her Egg Sac. We use the common name Cobweb Spider after Hogue in his wonderful book “Insects of the Los Angeles Basin, but BugGuide calls this the Long Bodied Cellar Spider.

Authors

    by
  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

14 thoughts on “Cellar Spider: All You Need to Know – Quick & Easy Facts”

  1. I am currently living in Germany for the next year and I have been finding these spiders all over my house. They usually stay up near the ceiling or in corners of the room, but they sometimes will drop down from the ceiling on a strand of their silk. Due to the number of these spiders I’m finding in my home, I feel I have to ask if they are at all poisonous? Personally I’ve always been fascinated by spiders and it’s never bothered me before to have them around but due to the fact that i have small children in my home and these spiders being so numerous,I’m concerned about the possibility of one of them being bitten.

    Reply
  2. While all spiders are venomous, not all venoms are harmful to us, and the cellar spider’s venom is one of them. The spiders also rarely bite and prefer to flee. Also, it’s a myth that these spiders have the deadliest venom in the world to humans but fangs are too small to pierce our skin. Their fangs can in fact pierce skin, but their venom isn’t dangerous to us and they rarely bite.

    Reply
  3. I have cellar spiders too (although I’m an arachnaphobe, these spiders are so flimsy and harmless I’m not too fearful of them) and have seen a great many over the last 15 years, but I have never seen a green one. “Mine” are always beige/grey. Amazing.

    Reply
  4. I would say it’ s from their last food – the Pholcus I am keeping for certain ID was yellow at first but after a fly’ s eyes it turned reddish and after more meals – brownish, – as their bodies are semitransparent. This one might have had eaten a lacewing or a green bug for example.

    Reply
  5. I came across this page trying to find more about a green spider I just saw. She was very similar to the one in the above photograph. I wondered as well re the type I encountered possibly being color-adaptive, as she was found among several green plant flakes; I saw the spider briefly as she ran due to my accidentally disturbing her for not seeing her resting or lurking among the flakes.

    Reply
  6. Sorry – PS – some difference to the photo, though: she had a very small body and very long legs. I thought she might be a (proper) daddy long legs, but she only had one segment that I could see of her tiny body so presumably she’s a type of cellar spider

    Reply

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