Black Widow -The black widow (female) is shiny black with a bright red hourglass shaped marking on the underside of the abdomen. The female hangs upside down in the web such that the red hourglass faces up. This spider is present in all 50 states and is found in Canada and South America. The silk strands of its web are considerably heavier and stronger than those of other spider species.. Black widows are classified as dangerous spiders because their bite can cause severe cramping and pain throughout the body. Very young children, the elderly, and very ill persons are most at risk for severe reactions to bites.
The Brown Recluse – Yellowish-tan to dark brown in color. It has dark brown legs covered with short, dark hairs. The brown recluse is identified by 3 pairs of eyes arranged in a semicircle on the front of the head and a violin-shaped marking behind the eyes. The neck of the violin points away from the head toward the abdomen. They are most active at night and prefer dark, undisturbed areas. The brown recluse is not aggressive but will bite if disturbed. Bites are rarely fatal but do require immediate attention by a physician as they cause ulcerating sores. Left untreated, such bites often become infected and significant tissue necrosis can occur.
House Spider – While there is not just one kind of house spider, a common house spider is the female S. grossa, 6-10.5 mm in length, and dark colored, with a round, bulbous abdomen. Like many spiders, the male is sometimes smaller; But can many times be nearly as long as the females. It measures 4.1-10.0mm in length, and is thinner than the female. They can go several months without feeding, provided they have access to water. A well fed female can lay 3 or more egg sacs each year, in which each egg sac typically contains between 40 – 100 eggs.
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