Insect Identification
Insect Identification

American House Spider - (Parasteatoda tepidariorum)

Authored By Staff Writer | Last Updated: 1/6/2016

The spindly-legged and everpresent American House Spider is also known by the cobweb it creates.

The webs created by American House Spiders are classic Halloween webs: tangled messes in all corners of the attic or windows. This type of web is called a cobweb. It is not uncommon for multiple females to have their webs in close proximity to one another. The presence of this spider adds a spooky atmosphere to old and abandoned buildings and homes.

The American House Spider is a Comb-Footed spider. It has long, skinny legs and comb-like hairs on the back tarsi ('ankles'). They fling strings of their spider silk at insects that get entangled in their web. The victim is then bitten, injected with venom and eaten at a later time. It is moved from the web to allow other prey to fall into the trap.

They have bulbous abdomen, neither spherical nor flat. This spider is inconspicuous and rarely bothers humans. They may opt to 'play dead' if threatened. If handled roughly though, they may bite. Their venom is not lethal to humans like their relative's, the Black Widow.

Smaller males approach a female's web when ready to mate. A courtship 'dance' or ritual follows, ensuring the spiders do not attack each other. Watch below to see a part of this ritual:

Females lay eggs in a pear-shaped, brownish egg case and hangs it from the web. Females guard their eggs until they hatch and can live fore more than a year.

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Category: Spider
Common name: American House Spider
Scientific Name: Parasteatoda tepidariorum
Other Names: Cobweb Spider, House Spider, Domestic Spider

  Kingdom: Animalia
   Phylum: Arthropoda
    Class: Arachnida
     Order: Araneae
      Family: Theridiidae
       Genus: Parasteatoda
        Species: tepidariorum

Adult Size (Length): 4mm to 6mm (0.16in to 0.24in)

Identifying Colors: brown; tan; black, white

Additional Descriptors: mottled, speckled, biting, venomous

North American Reach (Though Not Limited To*): Alabama; Alaska; Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Hawaii; Idaho; Illinois; Indiana; Iowa; Kansas; Kentucky; Louisiana; Maine; Maryland; Massachusetts; Michigan; Minnesota; Mississippi; Missouri; Montana; Nebraska; Nevada; New Hampshire; New Jersey; New Mexico; New York; North Carolina; North Dakota; Ohio; Oklahoma; Oregon; Pennsylvania; Rhode Island; South Carolina; South Dakota; Tennessee; Texas; Utah; Vermont; Virginia; Washington; West Virginia; Wisconsin; Wyoming; Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Nova Scotia; Ontario; Prince Edward Island; Quebec; Saskatchewan

* Keep in mind that insect reach is not governed by lines on a map and therefore may appear in areas/regions/states beyond those listed above.