This 2006 image depicted a female Aedes aegypti mosquito as she was completing the activity of obtaining a blood-meal from a human host through her fascicle, here red in color due to the blood contained therein, which she'd begun to resheath in her labium. Both structures are part of her feeding organ known as the proboscis. In this case, what would normally be an unsuspecting host was actually the CDC's biomedical photographer's own hand, which he'd offered to the hungry mosquito so that she'd alight, and be photographed while feeding. As it filled with blood, the abdomen became distended, stretching the exterior exoskeletal surface, thereby, causing it to become transparent, allowing the collecting blood to become visible as an enlarging intra-abdominal red mass, as is the case in PHIL# 9175, and 9176.
CDC/ Prof. Frank Hadley Collins, Dir., Cntr. for Global Health and Infectious Diseases, Univ. of Notre Dame
November 3, 2012