Your doctor may suspect a spider bite based on your history and your signs and symptoms, but a specific diagnosis is difficult to confirm. Confirmation requires:
- An eyewitness to the bite
- Identification of the spider by an expert
- Exclusion of other possible causes
Black widow identification
Some clues for identifying black widow spiders include:
- Shiny black body
- Large round abdomen
- Red hourglass on underside of abdominal area
- Central body about a half-inch (12 to 13 millimeters) long
- Entire body, including legs, can be more than an inch (2.5 centimeters) across
Brown recluse identification
Some clues for identifying brown recluse spiders include:
- Color ranges from yellowish tan to dark brown
- Dark violin shape on top of the leg attachment segment
- Six eyes — a pair in front and a pair on both sides — rather than the usual spider pattern of eight eyes in two rows of four
- Central body is a quarter-inch to three-quarters of an inch (6 to 19 mm) long
Aug. 23, 2017
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