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Pest Information

California common scorpion

  • Latin Name: Paruroctonus silvestrii
  • Common Name: California common scorpion
  • Other Names: N/A

Pest Details

Origin:

These are native scorpions. The family includes more than 84 species in the U.S. and they are distributed widely throughout the U.S. and western Canada, south through Central America.

Biology:

As with all scorpions the female retains the eggs that hatch within her and the young nymphs emerge and are herded up onto the back of the mother, where they then will remain for their first 2 to 3 weeks of life. They are nocturnal, foraging at night but remaining hidden during the daytime under objects on the soil as well as in shallow burrows. They are a very diverse group and found from desert habitats to high mountains. This species is one of the most common in California and may be most common in the arid southern areas of the state. The sting is considered to be painful but not particularly dangerous.

Identification:

Adults typically have a body length of 2 inches but large females may be nearly 3 inches long. Females in particular have an abdomen with a “fat” look to it, being much wider and more swollen in the middle and narrowed at each end. The overall color is tan with darker brown highlights and the top of the body tends to be a dark charcoal gray color. The claws have enlarged bases and relatively thick tips. The tail appendage segments are relatively stout and are striped along the ridges on the top and sides.

Characteristicts Important to Control:

An unusual feature of scorpions is that they will glow a light blue color when exposed to ultraviolet light at night, helpful when inspecting for them. Removal of harborage on a property is extremely important in their management, as these scorpions tend to prefer to hide under objects on the ground rather than burrow into the soil. Exclusion to prevent their entry into structures also is extremely important and should be a part of the overall management program. Residual contact insecticides applied to their likely hiding places will kill the scorpions, and treatments around the perimeter of a structure, focusing on likely entry areas, can be helpful.

Nibor D IGR 728x90
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