Black widow spiders can be recognized by which marking?

• A. Red hourglass marking on the dorsal side
• B. Red hourglass marking on the ventral side
• C. White stripes along the abdomen
• D. Blue spots on the legs

Answer: (B)

The essential idea is identifying black widows by a distinctive marking. The red, hourglass-shaped mark on the underside of the abdomen is the telltale feature used to recognize them. This ventral marking sets true black widows apart, since the top side is usually a plain, glossy black without that hourglass pattern. The other options don’t fit because white stripes along the abdomen or blue spots on the legs aren’t characteristic of black widows, and an hourglass on the top side would not match how the mark appears on this species. While related spiders can vary in color, the red hourglass on the underside is the classic identifying sign for the true black widow.