Malaria parasites. Image 7 of 10. Coloured transmission electron micrograph (TEM) of malaria sporozoites (brown) forming in a mosquito. This stage of the malaria (Plasmodium sp.) life cycle forms in the gut wall of a mosquito (Anopheles sp.) after the parasites are ingested during feeding on a human. They form asexually in an oocyst and infect humans when mature, carried in the saliva of the feeding mosquito. Later, malaria invades human red blood cells, causing recurrent fever, anaemia and even death. Magnification unknown. For the complete malaria parasite life cycle, see images M210/207-216.