LESSON 2
BITES AND STINGS
Section I. SPIDERS
2-1.
GENERAL
In the Continental United States (CONUS), insect bites and stings from
venomous arthropods may result in severe reactions that can cause death. Arthropods
most frequently reported as responsible for bites and stings are wasps, bees, ants,
spiders, and scorpions. In certain geographical locations in CONUS, some arthropods
have only seasonal importance while others are present throughout the year. Because
of the potential for arthropod poisoning to humans, their identification, distribution,
behavior, and control are important factors in the prevention of their bites and stings.
2-2.
CHARACTERISTICS OF THE BLACK WIDOW SPIDER
The black widow spider (Figure 2-1) is found in practically all parts of the western
hemisphere and has been recorded at an altitude of 8,000 feet in Colorado. It is known
as the "hourglass" spider since it has a reddish hourglass figure found on the underside
of its abdomen. It may be referred to as the "shoe button" spider also since its
abdomen is globose and likened to a shoe button. The adult female is easily identified
by its jet-black color and short almost microscopic hairs. It can be found in shady, cool
areas (in grass, shrubs, rock and brush piles, latrines, vacant rodent burrows, hollow
stumps, and similar places). The female black widow's abdomen is approximately 1/4"
long and its overall length is 1.5 inches with its legs extended. The male is somewhat
smaller. The male and immature females are gray in color and variously striped and
spotted. The venom from a black widow bite is more virulent per unit than that of a
rattlesnake. Although all spiders are not considered poisonous to man, all spider bites
must be considered serious wounds.
Figure 2-1. Black widow spider (bottom view).
MD0588
2-2