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Minist?rio da Sa?de. Funda??o Nacional de Sa?de. Instituto Evandro Chagas. Bel?m, PA, Brasil. Walter Reed Army Institute of Research. Washington, DC, USA. Minist?rio da Sa?de. Funda??o Nacional de Sa?de. Instituto Evandro Chagas. Bel?m, PA, Brasil. London School of Hygiene and Tropical Medicine. Department of Infectious and Tropical Diseases. Pathogen Molecular Biology and Biochemistry Unit. London, UK. London School of Hygiene and Tropical Medicine. Department of Infectious and Tropical Diseases. Pathogen Molecular Biology and Biochemistry Unit. London, UK. We conducted a survey to determine the vectors of malaria in six localities of Serra do Navio municipality, State of Amap?, from 1990 to 1991. Malaria infection rates of 29.3%, 6.2% and 20.4% were detected by human blood smears in Col?nia ?gua Branca, Porto Terezinha and Arrependido, respectively. There was no malaria infection detected in Serra do Navio. Fifteen species were identified among 3,053 anopheline mosquitoes collected by human bait and 64.4% were identified as Anopheles albitarsis s.l., 16.7% An. braziliensis, 9.5% An. nuneztovari and 5.8% An. triannulatus. An. darlingi, the main vector of malaria in the Amazon region of Brazil, was scare. Using enzyme-linked immunosorbent assay (ELISA), a total positive rate of 0.8% (23/2876) was found for six species: fifteen An. albitarsis s.l., four An. nuneztovari, and one of each: An. braziliensis, An. triannulatus, An. oswaldoi and An. rangeli. Nine of 23 positive mosquitoes were infected with Plasmodium malariae, eight with P. vivax VK210, three with P. vivax VK247 and three with P. falciparum. Since An. albitarsis s.l. was collected feeding on humans, was present in the highest density and was positive by ELISA for malaria sporozoites, it probably plays an important role in malaria transmission in this area.

Minist?rio da Sa?de. Funda??o Nacional de Sa?de. Instituto Evandro Chagas. Bel?m, PA, Brasil. The Hebrew University of Jerusalem. Faculty of Agriculture. Israel, ISR. Plasmodium neusticuri n.sp. (Apicomplexa: Plasmodiidae) ? descrito no sangue do lagarto Neusticurus bicarinatus (Lacertilia: Teiidae), na regi?o amaz?nica do Brasil. Todas as fases de desenvolvimento ocupam uma posi??o polar no gl?bulo vermelho, sem qualquer aumento no tamanho da c?lula hospedeira, e com pouca ou nenhuma deforma??o do n?cleo da mesma. Os trofozoitos produzem v?rios filop?dios compridos e um n?mero pequeno de gr?nulos de pigmento mal?rico de cor amarelo-verde escuro. Os esquizontes s?o menores que o tamanho do n?cleo do eritr?cito, e produzem 4 a 8 (usualmente 6) merozoitos que s?o irregularmente distribu?- dos na c?lula, mais ou menos 5 a 10 gr?nulos de pigmento ficam aglomerados no citoplasma. Os macrogamet?citos e os microgamet?citos s?o de forma elips?ide ou em "forma de rim", raramente redondos, com uma m?dia de 5.8 x 4.1 um e 5.8 x 4.4 um, respectivamente. S?o, geralmente, menores que o n?cleo da c?lula hospedeira, e possuem um vac?olo consp?cuo no citoplasma. Os gr?nulos de pigmento dos gamet?citos s?o mais numerosos e mais espalhados que aqueles encontrados nos esquizontes. Foram encontrados raros esquizontes exoeritroc?ticos nos mon?citos. At? agora, o vetor do parasita permanece desconhecido. Plasmodium neusticuri n.sp. (Apicomplexa: Plasmodiidae) is described in the blood of the lizard Neusticurus bicarinatus (Lacertilia: Teiidae) from Amazonian Brazil. Ali 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 ?m and 5.8 x 4.4 ?m, 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.

This work was supported by grant 078563 from the Wellcome Trust, London Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Bel?m, PA, Brasil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Bel?m, PA, Brasil. Universidade Estadual do Norte Fluminense. Centro de Bioci?ncias e Biotecnologia. Laborat?rio de Biologia Celular e Tecidual. Campos dos Goytacazes, RJ, Brazil. Plasmodium carmelinoi n. sp. is described in the teiid lizard Ameiva ameiva from north Brazil. Following entry of the merozoites into the erythrocyte, the young, uninucleated trophozoites are at first tearshaped and already possess a large vacuole: with growth, they may assume an irregular shape, but eventually become spherical or broadly ovoid. The vacuole reduces the cytoplasm of the parasite to a narrow peripheral band in which nuclear division produces a schizont with 8-12 nuclei. At first the dark, brownish-black pigment granules are restricted to this rim of cytoplasm but latterly become conspicuously concentrated within the vacuole. The mature schizonts are spherical to ovoid and predominantly polar in their position in the erythrocyte. They average 5.4 x 4,9 ?m (4.4 x 4.4 - 6.6 x 5,9 ?m), shape index 1.1, n = 50: 8-12 merozoites are produced and measure approximately 2.0 x 1,0 ?m. Mature gametocytes are also polar in position, and spherical to subspherical. The macrogametocytes measure 5.7 x 5,2 ?m (4.4 x 4.0 - 5.9 x 5,1 ?m), shape index 1.1, n = 50 and, following staining by Giemsa?s method, possess a compact, pink-staining nucleus and a clear blue, faintly stained cytoplasm. Microgametocytes are slightly larger, 6.0 x 5,0 ?m (5.2 x 4.4 ? 6.2 x 5,2 ?m), shape index 1.2, n = 45. They stain an over-all pink colour due to the dispersed nuclear chromatin. The vacuoles in both the macro- and microgametocytes are considerably smaller than those of the schizonts and of ovoid or spindle shape: they contain most of the pigment granules. The sex ratio, as seen in an inicial intense infection, was 1 male to 2.2 females. Prevalence of infection was low (5 %) but, due to the very low parasitaemia which may result in a failure to detect parasites, it is probably higher than this.