Source: U.S. National Park Service. Available online:
Black widow spiders (Latrodectus mactans) are found throughout the United States.
Female black widows are long-legged, shiny, coal-black spiders with an orange,
red, or yellow hourglass shape on their underside. Female black widows are
usually about 1.5 in. (3.8 cm)
across but may be smaller.
Primary Medical Reviewer
William H. Blahd, Jr., MD, FACEP - Emergency Medicine
William H. Blahd, Jr., MD, FACEP - Emergency Medicine & H. Michael O'Connor, MD - Emergency Medicine
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