This female Anopheles freeborni is taking a blood meal from a human host by pumping the ingested blood through her “labrum”, which is visible here as a thin red, “needle-like” structure between the mosquito’s head and the host’s skin.
Note her blood-filled, distended abdomen, which is so full that clear, fluid is spilling from the anus at the abdominal tip in order to make room for still more ingested blood.
During blood meals taken from persons infected with malaria parasites, the mosquitoes pick up parasites in their sexual forms, known as “gametocytes”.
After 10-18 days of further development within the mosquito, the parasites enter their “sporozoite” stage, and can be found in the mosquito’s salivary glands. In this way when the mosquito takes another blood meal, the parasites are introduced into another host, which could be another human being.
Source: Hardin MD/ University of Iowa
See more: Malaria (2)