The tarsus is the 'foot' segment of an insect leg — used in mosquito ID. Which body part is the tarsus?

• A. The leg segment nearest the body
• B. The "foot" segment of an insect leg — used in mosquito ID.
• C. The head segment of an insect leg
• D. A type of wing vein

Answer: (B)

The tarsus is the foot portion of the insect leg—the final segment that carries the foot and often contains several small subsegments (tarsomeres) and the claws. In mosquito identification, this foot region is frequently examined because leg patterns, banding, and the arrangement of segments on the tarsus help differentiate species.

Think of how the leg is built up from the body outward: the part closest to the body is the coxa, then the trochanter, femur, tibia, and finally the tarsus at the end. So the tarsus is not the segment right next to the body, and it’s not a wing feature. The options referencing the head or a wing vein misplace what the tarsus is. The correct idea is that the tarsus is the foot segment of the leg, used in mosquito ID.