Fig. 1

Exo-erythrocytic stages of avian malaria parasites: cryptozoites (a–c), metacryptozoites (d) and phanerozoites (e–l). Plasmodium cathemerium in wing skin of a domestic canary Serinus canaria approximately 2.5 days after inoculation of sporozoites (note small size of maturing cryptozoite, a). Plasmodium fallax in culture of brain cells from a turkey Meleagris gallopavo embryo (note five mature cryptozoic meronts and numerous mature dispersed merozoites, b). Plasmodium lophurae in culture of brain cells from a turkey embryo (note numerous small mature cryptozoic meronts located in groups, c). Plasmodium garnhami in histological section of liver of the hoopoe Upupa epops experimentally infected by sporozoites (note the plentiful basophilic cytoplasm and prominent different size nuclei in three metacryptozoic meronts in different stages of growth, d). Growing phanerozoic meront of Plasmodium gabaldoni in the spleen of the pigeon Columba livia infected by inoculation of infected blood (note the plentiful basophilic cytoplasm and prominent nuclei, e). Mature merozoites of Plasmodium gabaldoni in a brain smear of turkey experimentally infected by inoculation of infected blood (note prominent irregular shape nuclei in mature merozoites, f). Mature phanerozoic meront of Plasmodium durae in spleen of turkey experimentally infected by inoculation of infected blood (note small size of the mature meront and a deformed host cell nucleus, g). Plasmodium elongatum in a smear of bone marrow of a European greenfinch Carduelis chloris infected by inoculation of infected blood (note three intracellular parasites in different stages of growth in stem cells and one extracellular meront, h). Plasmodium huffi in a smear of bone marrow of a toco toucan Ramphastos toco experimentally infected by inoculation of infected blood (note one mature meront and several growing meronts, which markedly displace and deform host cell nuclei, i). Elongate phanerozoic meronts of Plasmodium gallinaceum blocking cerebral capillaries (note two meronts in different stages of growth, j). Mature phanerozoic meronts of Plasmodium pinottii in a brain smear of experimentally infected domestic pigeon Columba livia (k, l): note numerous roundish merozoites (micromerozoites, k) and elongate merozoites (macromerozoites, l) in cerebral capillaries. Simple long arrows meronts, triangle wide shot arrows host cell nuclei, simple arrowheads merozoites. Scale bars 10 μm