Insect Identification
Insect Identification

Sowbug Killer Spider - (Dysdera crocata)

Authored By Staff Writer | Last Updated: 8/13/2014

The Sowbug Killer is adept at keeping the local Roly Poly (or Sowbug) population under control.

This spider's favorite meal is the sowbug, also known as pill bug, wood louse, or roly poly, depending on where you live. Their coloration can range from a red thorax and ivory abdomen to a more purple thorax and tan abdomen. They have six eyes and those are arranged in an oval shape. Females are almost twice as large as males.

This spider is an active hunter, but it does have a lair. Inside, the remains of previous meals are usually found. It does not form webs to catch its prey. Instead, it finds a prey item (sow bug) and uses its giant chelicerae (jaws) to stab it in an ambush attack. Their venom is not toxic, but some people may experience itching at the site of a spider bite. This spider is not aggressive, nor interested in humans so bites are not common.

They use their silk to strengthen their homes, which are usually built under rocks, moss or tree bark. They can be found anywhere: fields, parking lots, gardens, etc. They are equally at home in urban, suburban and rural areas as are their favorite prey item (sow bugs). Look for them in the spring and summer, when they are most active. It is believed they overwinter as adults and reproduce in the spring.

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Category: Spider
Common name: Sowbug Killer Spider
Scientific Name: Dysdera crocata
Other Names: Woodlouse Spider, Woodlouse Hunter

  Kingdom: Animalia
   Phylum: Arthropoda
    Class: Arachnida
     Order: Araneae
      Family: Dysderidae
       Genus: Dysdera
        Species: crocata

Adult Size (Length): 9mm to 15mm (0.35in to 0.59in)

Identifying Colors: brown; red; yellow; ivory; orange; purple; tan

Additional Descriptors: jaws, 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; Mexico

* 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.