Woodlouse Hunter Spider

Dysderidae—Dysderid Spiders

Dysdera crocata

Originally from the Mediterranean region, Dysdera crocata has been introduced to South Africa, Australia, Chile, and Asia. In North America, it is found from New England to Georgia and west to California. 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.

Description

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.

Life History

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. Up to seventy eggs are 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.

Medical Importance

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.

Reference

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