PK-AR04 · Spiders, scorpions, and mites
How to get rid of Cellar spiders
Pholcidae
Cellar spiders are long-legged cobweb spiders in basement corners. Vacuum the web if you dislike looking at it. Numbers usually mean humidity and other insects, not a medical emergency.
They sit in messy corner webs and bounce when disturbed. They eat other arthropods, including sometimes more dangerous spiders. Harvestmen — the other animal also called daddy longlegs — have a fused oval body, no capture web, and wander on walls. Neither is a recluse. Glue boards in a basement will also catch pets; a vacuum is the usual tool if you want fewer webs.
How to identify Cellar spider
- Tiny body, very long thin legs, messy web in a corner, bounces in the web when disturbed.
- Eight eyes typically. Not a violin on the back.
Signs of an infestation
- Cobwebs in a basement ceiling corner.
- A spider that vibrates when you approach.
Biology and why they show up
Sit-and-wait in irregular webs. Prey includes other arthropods. Indoor year-round in heated buildings.
Health and property risk
Negligible medically. The meme is the harm — people smash useful predators.
Proven control sequence
Work in this order. Skipping inspection or exclusion is why most “treatments” bounce back in a week.
- Decide if you need control. Many entomologists leave them. Vacuum if you want clean corners.
- Reduce prey and clutter. They are a symptom of other insects.
Matching tools for these steps can be bought on Amazon. Buy the field kit.
Tools for cellar spiders
They hang in damp corners. Dry and vacuum the web. They are not a medical emergency.
As an Amazon Associate, Pest Kill earns from qualifying purchases. The EPA label is the law for any pesticide. These links match the sequence on this page — they are not a shopping list instead of identification. Details: advertising disclosure. Browse the full tools catalog.
Hardware
Pin-type wood moisture meter
Damp wood is carpenter-ant and termite language. A meter tells you if the sill, shower wall, or fascia is actually wet before you buy a spray. Wet still needs a building fix.
Hardware
Headlamp or flashlight for inspections
German cockroaches, rodent runways, and bed-bug harborages are night-shift jobs. A light you can point into a hinge beats another can of spray.
Cellar spider vs harvestman (daddy longlegs)
People use “daddy longlegs” for two animals. Cellar spiders (Pholcidae) have a two-part spider body and silk in corners. Harvestmen (Opiliones) are arachnids but not spiders: no venom fangs, no prey-capture web.
| Cellar spider | Harvestman | |
|---|---|---|
| Web | Messy corner cobweb; waits in it | No prey-capture web |
| Body | Tiny cephalothorax + abdomen | Fused, oval |
| Medical | Negligible | Negligible |
| If you want fewer | Vacuum webs; reduce other insects and humidity | Exclusion and less outdoor lighting of prey |
Prevention that actually sticks
- Less clutter, drier basements, fewer other pests.
When to hire a licensed professional
No.
United States and Tier 1 notes
Global indoor spider.
Common questions
Are daddy longlegs deadly?
No. Cellar spiders have negligible medical importance. Harvestmen are not spiders. The “most venomous but fangs too small” story is a meme, not entomology.
How do you get rid of cellar spiders?
Vacuum the web if you want them gone. Dry and destash the basement so prey declines. They are optional to treat.