A population of Pasmodium colmbiense sp. n. in the iguanid lizard, Anolis Auratus

Plasmodium colombiense sp. n. is described from 274 naturally infected Anolis auratus from western Colombia. Host blood pictures, parasitemia, parasite structure, infection states, and host population dynamics are correlated. Local epidemics occur, but in contrast to temperate zone species there is little regional synchronization. Active infections occur year-around, being somewhat more common in dry seasons; however, chronic infections predominate. Mature schizonts have 3 to 14, usually 6, 8, or 10 merozoites, reduced to 4 to 6 in chronic infections. Gametocytes are round to oblong, measuring 6 by 5 mu, and the pigment in microgametocytes occurs in a single peripheral vacuole. Parasitemia averaged 2.5% and seldom surpassed 20 to 30%. Infections cause significant anemia, and parasites in active infections are most common in immature erythrocytes. Host response is similar to avian or primate infections, including erythropoiesis, phagocytosis, and interference with parasite growth.