Identification of vector species (Diptera: Simuliidae) of human onchocerciasis in the Amazonia focus of Brazil and Venezuela

The taxonomic status of three Amazonian simuliid species, Simulium guianese Wise, S. oyapockense Floch & Abonnenc and S. yarzabali Ramirez Perez is reviewed. Simulium cuasisanguineum Ramirez Perez, Yarzabal & Peterson is synonymized with S. oyapockense, and S. yarzabali is revalidated from its synonymy with S. incrustatum Lutz. The role of these three species in the transmission of human onchocerciasis and mansonelliasis in Amazonia is reviewed.

The dermal leishmaniases of Brazil, with special reference to the eco-epidemiology of the disease in Amazonia

Six species of Leishmania are at present known to cause cutaneous and/or mucocutaneous leishamniasis in Brazil, and they are all to be found in the Amazon region of this country. The eco-epidemiology of each is discussed, with the observation that the Amazonian leishmaniases are all zoonoses, with their source in silvatic mammals and phlebotomine sandfly vectors. With man's destruction of the natural forest in southern Brazil, some sandfly species have survived by adapting to a peridomestic or domiciliary habitat in rural areas. Some domestic animals, such as dogs and equines are seemingly now involved in the epidemiology of the disease. No such process has yet been reported in the Amazon region, but may well take place with the continuing devastation of its forest.

A New Species of Simulium (Diptera: Simuliidae) from Open Areas in Central Amazonia, Brazil

The larva, pupa, male and female of Simulium daltanhani n. sp. are described and illustrated. This species shares diagnostic characteristics with Simulium quadrifidum Lutz, Simulium cauchense Floch & Abonnenc, Simulium brevifurcatum Lutz and Simulium siolii Py-Daniel. It was collected in three counties (Manaus, Presidente Figueiredo and Itacoatiara) in the State of Amazonas, Brazil. Its habitat includes streams in disturbed, open areas where the forest has been cut for road construction; it was not collected in adjacent forested streams, suggesting that it colonizes disturbed habitats. The larval subesophageal ganglion is discussed as a useful character, when pigmented, to distinguish this species within a limited geographic area.

Diversity of sandflies (Psychodidae: Phlebotominae) captured in sandstone caves from Central Amazonia, Brazil

In the present paper we describe the diversity of phlebotomine sandflies collected in three sandstone caves in the municipality of Presidente Figueiredo, state of Amazonas, Brazil. The phlebotomines were captured during 2006 with CDC light traps. Guano samples from inside the Gruta Refúgio do Maruaga were collected to investigate the presence of immature specimens. A total of 2,160 adult phlebotomines representing 15 species were captured. Pintomyia pacae was the dominant species in Gruta dos Animais (1,723 specimens) and Gruta dos Lages (50 specimens) and Deanemyia maruaga new comb (280 specimens) was the dominant species in Gruta Refúgio do Maruaga. A total of 18 guano samples were collected and seven of these samples included immature specimens. A total of 507 immature specimens were captured; 495 of these specimens were larvae and 12 were pupae. The presence of paca (Agouti paca) footprints near Gruta dos Animais and Gruta dos Lages suggests the association of Pi. pacae with this rodent. This finding may explain the abundance of Pi. pacae in these locations, while the species is relatively rare in the forest. Deanemyia maruaga is a cave species that uses guano to breed during its immature stages. Adult specimens of this species are apparently parthenogenetic and autogenous and represent the second record of parthenogenesis for the subfamily Phlebotominae.

An illustrated key to nymphs of Perlidae (Insecta, Plecoptera) genera in Central Amazonia, Brazil

An illustrated key to nymphs of Perlidae collected in streams of Central Amazonia, Brazil is provided. Three genera are reported for this region: Macrogynoplax Enderlein, Anacroneuria Klapálek and Enderleina Jewett. Additional diagnostic characters are provided for Enderleina nymphs.

New species and records of Chimarra Stephens (Trichoptera, Philopotamidae) from Central Amazonia, Brazil

Chimarra (Curgia) paucispina sp. nov., of the aurivittata group Flint, 1998 is described and illustrated from specimens collected in Amazonas State. The key to species of Chimarra (Curgia) Walker, 1860 presented by Flint was modified to include the new species. Chimarra (Chimarrita) chela Blahnik, 1997 and Chimarra (Curgia) jugescens Flint, 1998 are for first time reported for the Amazonas State. This is the first record of C. chela in Brazil.

Mosquitoes (Diptera, Culicidae) inhabiting foliar tanks of Guzmania brasiliensis Ule (Bromeliaceae) in central Amazonia, Brazil

Mosquitoes in the family Culicidae develop their immature forms in different environments depending on various circumstances. This study represents the first contribution to the ecological knowledge of culicids living in the bromeliad G. brasiliensis. The objectives of the study were to compare the Culicidae fauna of bromeliads in two seasonal periods, analyzing their abundance, richness and the influence of pH, conductivity and water volume, on the populations. Sampling was done at Reserva Adolpho Ducke, Manaus, Amazonas, Brazil between 2003 and 2005. Six samplings were done in the rainy season and six in the dry season. On each sampling day, six terrestrial and six epiphytic bromeliads, totaling 144 sampling units, were retrieved. A total of 444 immature mosquitoes were collected, distributed in the following species: Culex (Microculex) stonei Lane & Whitman, Culex (Microculex) chryselatus Dyar & Knab, Culex (Microculex) sp., Wyeomyia (Hystatomyia) autocratica Dyar & Knab and Wyeomyia (Hystatomyia) splendida Bonne-Wepster & Bonne. The relationship between abundance of Culicidae and sampling period was not significant, although abundance was higher in the dry period. There were significant correlations between water volume and the abundance (p = 0.003) and richness (p = 0.001) of culicids. The pH was positively related to the occurrence of the species Wy. autocratica (p= 0.010) and Wy. splendida (p= 0.006), demonstrating the influence of this factor in the structuring of bromeliad-inhabiting communities.

Sand flies (Diptera, Psychodidae, Phlebotominae) from Central Amazonia and four new records for the Amazonas state, Brazil

Sand flies from Central Amazonia and four new records for the Amazonas state, Brazil. A survey was conducted in May and June 2008 to study the fauna of insects in Central Amazonia, Brazil. As part of the survey, we report here that sixty species of phlebotomine were identified, totaling 13,712 specimens from 13 genera. The collection sites were located at the border between the states of Pará and Amazonas, comprising three municipalities from the Amazonas state (Borba, Maués, and Nhamundá). Malaise, CDC and Shannon traps were used to collect the insects. Most of the sand flies were collected by CDC traps (89.5%), while Malaise and Shannon traps collected 7% and 3.5%, respectively. The most abundant genera, representing 97.1% of the total sand flies identified were: Trichopygomyia Barretto, 1962 (47.6%), Psathyromyia Barretto, 1962 (17.9%), Psychodopygus Mangabeira, 1941 (17.5%) and Trichophoromyia Barretto, 1962 (14.3%). The genera with the largest number of species identified were: Psychodopygus (14), Psathyromyia (10), Evandromyia Mangabeira, 1941 (7), Trichophoromyia (5) and Trichopygomyia (5). The most abundant species was Trichopygomyia trichopyga (Floch & Abonnenc, 1945), which represented 29% of the total sand flies identified. Here we also report new records for four species in the Amazonas state: Ps. complexus (Mangabeira, 1941), Ps. llanosmartinsi Fraiha & Ward, 1980, Ty. pinna (Feliciangeli, Ramirez-Pérez & Ramirez, 1989), and Th. readyi (Ryan, 1986). The results of this study provide new, additional information on the distribution of sand flies in the Amazon and increase the number of species in the Amazonas state from 127 to 131.

Epidemiology and control of frontier malaria in Brazil: lessons from community-based studies in rural Amazonia

We describe the epidemiology of malaria in a frontier agricultural settlement in Brazilian Amazonia. We analysed the incidence of slide-confirmed symptomatic infections diagnosed between 2001 and 2006 in a cohort of 531 individuals (2281.53 person-years of follow-up) and parasite prevalence data derived from four cross-sectional surveys. Overall, the incidence rates of Plasmodium vivax and P. falciparaum were 20.6/100 and 6.8/100 person-years at risk, respectively, with a marked decline in the incidence of both species (81.4 and 56.8%, respectively) observed between 2001 and 2006. PCR revealed 5.4-fold more infections than conventional microscopy in population-wide cross-sectional surveys carried out between 2004 and 2006 (average prevalence, 11.3 vs. 2.0%). Only 27.2% of PCR-positive (but 73.3% of slide-positive) individuals had symptoms when enrolled, indicating that asymptomatic carriage of low-grade parasitaemias is a common phenomenon in frontier settlements. A circular cluster comprising 22.3% of the households, all situated in the area of most recent occupation, comprised 69.1% of all malaria infections diagnosed during the follow-up, with malaria incidence decreasing exponentially with distance from the cluster centre. By targeting one-quarter of the households, with selective indoor spraying or other house-protection measures, malaria incidence could be reduced by more than two-thirds in this community. (C) 2010 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

Feeding ecology of Auchenipterichthys longimanus (Siluriformes: Auchenipteridae) in a riparian flooded forest of Eastern Amazonia, Brazil

Neste estudo foram investigados os hábitos alimentares do bagre Auchenipterichthys longimanus coletados em rios da Floresta Nacional de Caxiuanã (Amazônia Oriental, Brasil) ao longo de diferentes períodos hidrológicos (seco, enchendo, cheio e vazando). Foram coletados 589 espécimes durante sete amostragens, entre julho de 2008 e julho de 2009, dos quais 74eram machos jovens, 177 machos adultos, 89 fêmeas jovens e 249 fêmeas adultas. A composição da dieta, analisada pelo Índice de Importância Alimentar (IAi%) foi avaliada por um escalonamento multidimensional não-métrico (nMDS) e pela análise de similaridade (ANOSIM), que incluiu 37 itens alimentares agrupados em nove categorias (insetos aquáticos, outros invertebrados aquáticos, fragmento de artrópodes, peixe, fragmento de planta, sementes, insetos terrestres, outros invertebrados terrestrese vertebrados terrestres). Também foram obtidos a amplitude de nicho (Índice de Levins) e o Índice de Repleção (IR%) da dieta do bagre. Foram observadas diferenças na composição da dieta entre os períodos hidrológicos, principalmente relacionada à estação seca e cheia, mas não houve variação na composição da dieta entre os sexos e maturidade. No período de cheia (especificamente no mês de março/2009) o bagre mostrou uma alimentação mais especialista enquanto que no período de seca (novembro/2008) os valores de amplitude de nicho classificaram-no com hábitos mais generalistas quanto a alimentação. A quantidade de alimentos ingeridos por A. longimanus com base no Índice de Repleção (IR%), não diferiram significativamente entre o sexo e maturidade. No entanto, foram evidenciadas diferenças quando comparados os meses estudados. Estes resultados fornecem informações biológicas importantes sobre a ecologia trófica de peixes da família Auchenipteridae. Tendo em vista a maior ocorrência de itens alóctones na dieta deste bagre, esta pesquisa também reforça a importância das matas ciliares em ambientes críticos na manutenção e conservação das populações selvagens de peixes na bacia amazônica.

Feeding ecology of Dash-dot Tetra Hemigrammus belottii (Steindachner 1882) (Characiformes: Characidae) in the streams of the Urucu River basin, central Amazonia, Brazil

O presente estudo descreve a dieta da espécie Hemigrammus belottii (Characiformes: Characidae) coletados na bacia do Rio Urucu no município de Coari, Amazonas, (Brasil), buscando responder o seguinte questionamento: Qual a influência dos períodos hidrológicos (seco e chuvoso) e da distribuição espacial na dieta de H. belottii? Os espécimes tiveram seus estômagos retirados e os itens alimentares pesados e identificados para posteriores análises relacionadas à intensidade alimentar, pelo Índice de Repleção (IR%) e pelo índice de importância alimentar (IAi%). Foi analisado um total de 227 espécimes, com comprimento padrão médio de 16,54 mm ± 5,6 mm. Baseado no IR% verificou-se para H. belottii uma maior intensidade alimentar durante o período da seca. A dieta da espécie foi composta predominantemente pelos itens Formicidae (IAi% = 69,6), fragmento de exoesqueleto alóctone (IAi% = 17,7) e Coleoptera (IAi% = 6,0), com sua composição se mostrando independente de períodos hidrológicos e de sua distribuição espacial, que pode ser atribuído à alta disponibilidade de itens alimentares utilizados pela espécie durante o ano todo. De um modo geral H. belottii evidenciou um hábito alimentar insetívoro generalista, com predomínio de itens de origem alóctone.

Mangrove vegetation in Amazonia: a review of studies from the coast of Pará and Maranhão States, north Brazil

O presente estudo apresenta uma compilação da literatura sobre a vegetação dos manguezais da costa norte do Brasil, apresentando uma síntese do conhecimento e listando a literatura disponível. O estudo se concentra na costa dos estados do Pará e Maranhão que formam um cinturão contínuo de manguezais. Foram contabilizadas seis espécies arbóreas exclusivas de mangue e várias outras associadas. A altura e o diâmetro das árvores de mangue variam em função de parâmetros abióticos locais. As variações sazonais do regime de chuvas e da salinidade afetam a fenologia das espécies e a produção de serapilheira. A população costeira utiliza a flora do manguezal para diferentes fins (ex: combustível, medicinal, construção rural). O aumento da ocupação costeira inicia um processo de impacto para as florestas de mangue e a disponibilidade de seus recursos.

Ethnoveterinary knowledge of the inhabitants of Marajó Island, Eastern Amazonia, Brazil

Em várias partes do mundo existem relatos etnoveterinários sobre a utilização de plantas em protocolos terapêuticos, entretanto não existem informações disponíveis sobre a etnoveterinária praticada na Amazônia brasileira. Desta forma, objetivou-se documentar o conhecimento etnoveterinário de habitantes da Ilha do Marajó, Amazônia Oriental. Foram realizadas 50 entrevistas individuais com aplicação de questionários semi-estruturados que foram analisados quantitativamente através de estatística descritiva utilizando freqüência de distribuição. O valor de uso foi calculado para determinar as espécies mais importantes. Amostras de plantas com relatos de uso medicinal foram coletadas e identificadas botanicamente. Cinqüenta plantas, distribuídas em 48 gêneros e 34 famílias, foram indicadas para 21 diferentes usos medicinais. A família Asteraceae foi a que teve maior número de espécies citadas e Carapa guianensis Aubl, Crescentia cujete L., Copaifera martii Hayne, Caesalpinia ferrea Mart., Chenopodium ambrosioides L., Jatropha curcas L. e Momordica charantia L. foram as espécies com maiores valor de uso. As partes das plantas mais utilizadas para preparo dos medicamentos etnoveterinários foram folhas (56%), cascas (18%), raizes (14%), sementes (14%) e frutos (8%). Quanto à forma de uso o chá foi citado por 56% dos entrevistados e a maioria das preparações (90,9%) utiliza uma só planta. Além das plantas medicinais, os entrevistados relataram o uso de produtos de origem animal e mineral. Esse trabalho contribui para realização de um inventário das plantas utilizadas na etnoveterinária marajoara que pode servir de base de dados para futuros estudos de validação científica.

A new genus and two new species of Opilioacaridae (Acari: Parasitiformes) from Amazonia, Brazil with a key to world genera

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Brasilacarus cocaris (Acari: Opilioacaridae), a new genus and species from Amazonia, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)