1. BLACK WIDOW SPIDER
(Latrodectus mactans)
[Illustration: (unlabelled)]
Identification. The female black widow has a shiny black body,
approximately 1.5 cm (0.6 in) long, and usually a red hourglass-shaped
marking on the underside of her globose abdomen. On some individuals the
distinct hourglass marking is replaced with several triangles or spots
or an irregular longitudinal blotch. She has slim black legs with a span
of 4 cm (1.5 in). The male is considerably smaller than the female,
usually a patterned brown color, and is not a threat to man.
Distribution. _Latrodectus mactans_ is found in every state except
Alaska; however, most reported human fatalities have occurred in the
Southeastern States.[14, 15]
Biology/Behavior. The black widow is generally found in its
irregular-shaped web near the ground. Common web sites are under stones,
loose bark, or water faucets or in wood piles, rodent burrows, garages,
storage buildings, outhouses, and barns. Most human envenomizations
occur when the spider is inadvertently trapped against part of the body
or when the web is accidentally touched.
Avoidance/Control. Frequent cleaning to remove spiders and their webs
from buildings and outdoor living areas will decrease the possibility of
accidental bites. Routine hose washings of potential spider habitats,
such as under steps and around windows and doors, will discourage the
black widow from locating in these places. When working in
spider-infested areas, wear gloves and a long-sleeved shirt. If
warranted, the outside or inside of a building may be sprayed with an
approved insecticide. Apply the spray around windows, stairs, closets,
or other spider habitats in accordance with instructions on the
manufacturer’s label.