THE MERCK MANUAL: The Merck Manual of Diagnosis and Therapymultimedia

Return to Topic

  • Spider Bites
  • Black Widow Spider

    photo size: small | high

    Black Widow Spider

    A black widow spider is typically one-half to one inch long. The female, which is more common, has a reddish hourglass marking (shown) on the abdomen.

    Photo courtesy of Mike Cardwell (Extreme Wildlife Photography, Sacramento, CA).