Spider: The Woodlouse Hunter
Dysdera crocata is a hunting spider found from New England to Georgia and west to California. It is also a commonly encountered spider in England, northern Europe, and Australia. The woodlouse hunter preys on pill bugs or sow bugs (order Isopoda) and derives its common name from the British common name for these crustaceans. D. crocata is known to feed on other arthropods as well. This is the only species of the family Dysderidae known to occur in Pennsylvania.
Female D. crocata are 11 to 15 millimeters in length, and the males are 9 to 10 millimeters. The cephalothorax and legs are reddish-orange and the abdomen is a dirty white. The chelicerae are large, thick, and slanted far forward. The six eyes are arranged in an oval.
The woodlouse hunter probably overwinters in its adult form. Mating is reported to occur in April, with the eggs being deposited shortly thereafter. The eggs are suspended within the female’s silken retreat by a few strands of silk. Seventy eggs may be deposited at a time. The spiderlings will remain with the mother at first, living in her retreat for a period before moving out on their own.
D. crocata bites have been implicated in causing a localized, intensely itching erythema 4 to 5 millimeters in diameter. The bites apparently do not result in any systemic neurotoxicity or cytotoxicity.
Authored by: Steve Jacobs, Sr. Extension Associate
March 2002 Revised 2012This publication is available in alternative media on request.
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