Origin:
This species is native to much of South America, but commonly hitchhikes on exported materials. It has been found in several Central America countries, in Finland, and in scattered states in the U.S., including California, Florida, Massachusetts, and Kansas. It does not appear currently to be a breeding resident in North America.
Biology:
This is one of the largest of the Loxosceles species, with a body length of around 5/8 inch. It is not a resident spider in the U.S. as far as is known, but has been discovered a number of times, associated with imported materials from South America. Females create an egg sac and deposit up to 50 eggs in it, with a potential to create 5 egg batches in one year. Development from egg to adult requires about 1 year and they can live for up to 7 years. They are nocturnal and prefer to live and forage in locations that have little other activity. These are not aggressive spiders and bites are rare. Recent opinion from the University of California suggests that the venom of this species should be considered equal in potency to that of the Brown Recluse, but this remains unproven. The venom is, however, capable of causing skin disruption and lesions but for 90% of proven victims of a bite the wound heals quickly and without scarring.
Identification:
The ideal character that is distinctive for the Loxosceles spiders is the arrangement and number of eyes. They have only 6 eyes, whereas most other spiders have 8, and the 6 eyes are arranged as 3 pairs in a wide arc across the top-front of the head. There also will normally be a darker “violin” shaped pattern on top of the cephalothorax, with the widest part at the front. The color of the cephalothorax is reddish brown, the abdomen grayish brown, the legs are very long and relatively hairless, and with legs spread outward the spider may have a diameter of about 2 q inches. The cephalothorax is round in appearance and the abdomen is narrower and covered with very short hairs that give it a dull look.
Characteristicts Important to Control:
As with most spider control habitat modification is important, removing or elevating all materials on the soil that might serve as a hiding place and moving firewood and other unnecessary materials away from the structure. These are hunting spiders that do not spin webs for the capture of food. A good program of exclusion should take place to permanently close all openings the spiders may use for entry to structures. The use of a labeled residual, contact insecticide around doorways and windows, entry points, and into possible harborage will help to kill the spiders. This species is not likely to take up residence within a structure.
