This photomicrograph of a blood smear contains a microgametocyte of the parasite Plasmodium vivax.
Both macro- and microgametocytes are products of the erythrocytic cycle. The gametocytes are infectious to mosquitoes when ingested. In the intestine of the mosquito, the microgametocyte enters the macrogametocyte, and zygotes are produced. (Lower magnification image.)
Mae Melvin, Wikimedia Commons
A thin-film Giemsa stained micrograph of ring-forms, and gametocytes of Plasmodium falciparum. (Higher magnification image.)
TimVickers, English Wikipedia
Giemsa-stained thin smears of Plasmodium knowlesi infecting human red blood cells. Various life stages shown: early trophozoite (top left), late trophozoites (top right), schizont (bottom left), gametocyte (bottom right).
Kim-Sung Lee, Janet Cox-Singh, Balbir Singh, Wikimedia Commons