Development of Hepatozoon caimani (Carini, 1909) Pessôa, De Biasi & De Souza, 1972 in the Caiman Caiman c. crocodilus, the frog Rana catesbeiana and the mosquito Culex fatigans

The sporogony of Hepatozoon caimani has been studied, by light microscopy, in the mosquito Culex fatigans fed on specimens of the caiman Caiman c. crocodilus showing gametocytes in their peripheral blood. Sporonts iniciate development in the space between the epithelium of the insect gut and the elastic membrane covering the haemocoele surface of the stomach. Sporulating oocysts are clustered on the gut, still invested by the gut surface membrane. Fully mature oocysts were first seen 21 days after the blood-meal. No sporogonic stages were found in some unidentified leeches fed on an infected caiman, up to 30 days following the blood-meal. When mosquitoes containing mature oocysts were fed to frogs (Leptodactylus fuscus and Rana catesbeiana), cysts containing cystozoites developed in the internal organs, principally the liver. Feeding these frogs to farm-bred caimans resulted in the appearance of gametocytes in their peripheral blood at some time between 59 and 79 days later, and the development of tissue cysts in the liver, spleen, lungs and kidneys. Transmission of the parasite was also obtained by feeding young caimans with infected mosquitoes and it is suggested that both methods occur in nature. The finding of similar cysts containing cystozoites in the semi-aquatic lizard Neusticurus bicarinatus, experimentally fed with infected C. fatigans, suggests that other secondary hosts may be involved

Plasmodium neusticuri n. sp. (Apicomplexa: Plasmodiidae), a parasite of the lizard Neusticurus bicarinatus (Lacertilia: Teiidae) in Amazonian Brazil

Plasmodium neusticuri n.sp. (Apicomplexa: Plasmodiidae) is described in the blood of the lizard Neusticurus bicarinatus (Lacertilia: Teiidae) from Amazonian Brazil. All stages of the parasite occupy a polar position in the erythrocyte and produce no enlargement of the host cell and little or no distortion of its nucleus. Trophozoites commonly display a variable number of long filopodia, and quickly produce a small number of dark, yellow-green pigment granules. Meronts are smaller than the host-cell nucleus. They are broadly ellipsoidal to spherical, produce 4-8 (usually 6) merozoites disposed in an irregular manner, and have some 5-10 pigment granules forming a loose clump. Macrogametocytes and microgametocytes are broadly ellipsoidal, frequently "kidney-shaped", rarely spherical.They are generally smaller than the host-cell nucleus, averaging 5.8 x 4.1 mum and 5.8 x 4.4 mum, respectively. Both usually exhibit a conspicuous cytoplasmic vacuole, and their pigment granules are more abundant and scattered than those of the meronts. Rare examples of extraerythrocytic meronts were encountered in monocytes. The vector of the parasite is at present unknown.

A new filaria of a lizard transmitted by sandflies

A description is given of Madathamugadia wanjii n. sp., a Splendidofilariinae parasite of the gecko Ptyodactylus hasselquistii, on the west bank of the River Jordan and of its life cycle in Phlebotomus duboscqi. The new species is close to M. ivaschkini (Annaev, 1976) n. comb., of Turkmenistan, wich is also transmitted by sandflies (Reznik, 1982). The genus Madathamugadia is now comprised of four species, two from Madagascar and two from the Mediterranean sub-region; it differs from the genus Thamugadia by the presence of a double row of papillae anterior to the cloaca of the male. The larval characters of Splendidofilarinae of lizards confirm the affinity of these parasites to the Splendidofilarinae of birds (Chandlerella and Splendidofilaria); the first group could have arisen from the second by "captures" wich could have occurred in several places