Bug Identifier

Spiders

Cellar Spider

Pholcus phalangioides

0246810
Body length in millimeters. Shaded bar shows the typical adult range.
Scientific namePholcus phalangioides
GroupSpiders
Size7–10 mm (up to about 0.39 in)
Colors Tan and Gray
Legs8 legs
WingsNo (as usually seen)
Where foundBasement or garage and Bathroom
Most activeSpring, Summer, Fall and Winter
BitesNo
StingsNo
Risk levelHarmless

How to identify it

The cellar spider is a small member of the spiders group. Eight legs, two body sections and silk-spinning organs at the rear. Check for these three features:

  1. Tiny, peanut-shaped body with very long, hair-thin legs
  2. Loose, messy webs in ceiling corners
  3. Shakes its web rapidly when touched

About this bug

A pale, delicate spider with extremely long, thin legs that hangs upside down in loose webs in basements and ceiling corners. When disturbed, it vibrates rapidly in its web.

You'll usually find cellar spiders in basements and garages and in the bathroom. They are most active in spring, summer, fall and winter.

Is it dangerous?

Cellar spiders are harmless to people; the myth that they are deadly but can't bite is false.

Our rating: Harmless, meaning it poses no real threat to people, pets or property.

When you'll see cellar spiders

Cellar Spiders are most active in spring, summer, fall and winter. In spring, overwintering adults become active and many species lay their first eggs. Summer heat speeds up development, so populations can grow quickly. In fall, many bugs look for shelter, and some move toward or into buildings. In winter, activity continues mainly indoors in heated spaces.

Typical places to check: basement or garage and bathroom.

About spiders

The cellar spider is one of the spiders. Spiders have eight legs, two main body sections and no antennae. Almost all spiders have venom to subdue prey, but only a few have venom that matters to people. Many build webs, while others, such as wolf spiders and jumping spiders, hunt on foot.

Spiders go where their food is. A home with lots of spiders usually has plenty of other insects, so general pest control reduces spiders too.

Should you get rid of it?

No control is needed. Cellar Spiders are not pests, and many help by eating other insects or pollinating plants. If one is indoors, move it outside with a cup and a sheet of paper.

Bugs that look similar

HarvestmanOpiliones order2–7 mmHarmless

Group: Cellar Spider belongs to spiders, while harvestman belongs to ticks, mites & other arachnids. Eight legs, two body sections and silk-spinning organs at the rear.

Crane FlyTipula spp.10–35 mmHarmless

Group: Cellar Spider belongs to spiders, while crane fly belongs to flies & mosquitoes. Eight legs, two body sections and silk-spinning organs at the rear.

Brown Recluse SpiderLoxosceles reclusa6–20 mmHealth risk

Size: Brown Recluse Spiders are larger, reaching 20 mm, while cellar spiders top out around 10 mm.

Common House SpiderParasteatoda tepidariorum4–8 mmHarmless

Size: Cellar Spiders are larger, reaching 10 mm, while common house spiders top out around 8 mm.

Frequently asked questions

What does a cellar spider look like?

Tiny, peanut-shaped body with very long, hair-thin legs. Adults measure 7–10 mm (up to about 0.39 in).

Does the cellar spider bite or sting?

It does not bite. It does not sting. Cellar spiders are harmless to people; the myth that they are deadly but can't bite is false.

Where do cellar spiders live?

Cellar Spiders live in basements and garages and in the bathroom.

When are cellar spiders most active?

Mostly in spring, summer, fall and winter.