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ABSTRACT. 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: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 bromeliadinhabiting communities.KEYWORDS. Amazon; Aquatic insects; Culex (Microculex); Phytotelmata; Wyeomyia.RESUMO. Mosquitos (Diptera, Culicidae) habitando tanques foliares de Guzmania brasiliensis Ule (Bromeliaceae) na Amazônia Central, Brasil. Mosquitos da família Culicidae desenvolvem suas formas imaturas em vários ambientes na dependência de circunstâncias diversas. Este trabalho representa a primeira contribuição ao conhecimento ecológico de culicídeos em G. brasiliensis e tem como objetivo inventariar os imaturos em bromélias em dois períodos sazonais, analisando a abundância, riqueza e a influência das variáveis abióticas pH, condutividade e volume de água sobre as populações de Culicidae. A relação entre abundância de Culicidae e períodos não foi significativa, entretanto, o período seco apresentou maior representatividade de imaturos. Houve significância na relação do volume de água e abundância (p= 0,003) e riqueza (p= 0,001) de culicídeos. O pH foi o único parâmetro relacionado positivamente com a ocorrência das espécies Wy. autocratica (p= 0,010) e Wy. splendida (p= 0,006) ressaltando a influência deste fator na estruturação das comunidades bromelícolas.

The aim of this work was to investigate the diversity of macroinvertebrates and also verify if the abundance and diversity of Diptera were influenced by the abiotic factors. The samples were collected from the epiphytic and terrestrial bromeliads G. brasiliensis (1 and 3m) in wet and dry seasons at Reserva Adolpho Ducke analyzed total of 144 samples were analyzed from a total of 15,238 individuals collected. These conatined 14,097 insects and, among these, 8,258 were immature Diptera, represented by eight most abundant families: Chironomidae, Ceratopogonidae and Culicidae. The relationship of Diptera diversity was influenced by the seasons and stratifications (p= 0.01); the abundance was influenced by the volume of water (p= 0.02) and the relationship between the season and volume of water in the terrestrial bromeliads was significant (p= 0.01). This study represented the first contribution to knowledge of community of macroinvertebrates associated to bromeliads G. brasiliensis in Central Amazon

Alocasia macrorrhizos (L.) G.Don grows and proliferates in shaded areas in several forest fragments in urban zones. The adult plant has axils that accumulate rain water (phytotelmata) and serve as breeding sites for several families of aquatic insects. The objective of this study was to determine the composition of the entomofauna associated with water accumulations in axils of A. macrorrhizos in urban areas of Manaus, Brazil. Individuals of A. macrorrhizos were sampled in five forest fragments, between April/2005 and March/2007 in urban areas of Manaus, totaling 184 sampling units. A manual suction hose was used for the removal of entomofauna. A total of 1,941 immatures of Diptera were collected representing the following families: Culicidae (96.5%), Chironomidae (2%), Psychodidae (0.7%), Ephydridae (0.7%) and Corethrellidae (0.1%). Five Culicidae species were identified: Wyeomyia melanocephala Dyar & Knab, 1906 (91.7%), Wy. ypsipola Dyar, 1922 (4.3%), Aedes albopictus (Skuse, 1894) (2.3%), Ae. aegypti (Linnaeus, 1762) (1.5%) and Johnbelkinia longipes (Fabricius, 1805) (0.1%). The members of Culicidae were the most abundant, confirming the importance of this group in communities associated with phytotelmata, with a positive relation to the volume of water (p < 0.05). The occurrence of Ae. aegypti and Ae. albopictus in axils of A. macrorrhizos demonstrates the potential of this Araceae as a breeding site of these medically important species. However, the real contribution of this Araceae in the maintenance and dispersion of populations of these two species of mosquitoes throughout the year should be further studied.

Resumen Con el propósito de determinar si existe una periodicidad en la deriva de la entomofauna en una quebrada de aguas limnológicamente clasificadas como de tipo negras en la Amazonia Central, un muestreo intensivo fue realizado en el Igarapé de la Onça, en el kilometro 20 de la carretera que comunica los municipios de Presidente Figuereido y Balbina (Amazonas). Las colectas fueron realizadas con redes fijas de 300 micrómetros de malla, en periodos de dos horas de duración y a intervalos de seis horas, siendo las muestras fijadas en alcohol. La velocidad media de la corriente en la quebrada fue medida en tres sustratos diferentes (rugoso, liso y pedregoso), obteniendo una media de 10 m/seg. La abundancia de individuos no presentó diferencia entre los dos puntos de colecta establecidos. En términos de la periodicidad, se observó una mayor densidad de organismos y riqueza biológica durante el crepúsculo (horario de las 18:00-20:00 horas), lo que sugiere una estrategia de respuesta a las relaciones predadorpresa, con un aumento de actividad de algunas especies en la ausencia de luz. Con base en los resultados de este estudio, surge la necesidad de saber si esta estrategia corresponde a una sincronización reproductiva o trófica de los insectos acuáticos, para evitar la predación.

ABSTRACT. The last-stage larva of Bromeliagrion rehni Garrison in De Marmels & Garrison, 2005 is described and illustrated and bionomics and habitat information on this species are provided. The study was conducted in the Reserva Florestal Adolpho Ducke, located near Manaus, state of Amazonas, Brazil.Twelve samplings were done between April, 2003 and April, 2005: six in the rainy season and six in the dry season. In each sampling month, 12 bromeliads (Guzmania brasiliensis Ule, 1907, Bromeliaceae) were collected, six of which were terrestrial and six epiphytic, yielding144 samples. A total of 75 specimens of B. rehni were collected. The relationship between larval B. rehni abundance and the measured environmental parameters (volume (ml), pH, season and stratum) was significant (ANCOVA, F = 5.296, d.f. = 130, p < 0.001). Larvae were most abundant in the rainy season (p < 0.01) and water volume was positively related to the abundance of B. rehni. Larvae of B. rehni can be distinguished from those of B. fernandezianum (the only species in the genus with described larvae) by the number of setae in the prementum and by the color of the apical region of the femur. The association of this species with phytotelmata of G. brasiliensis is reported here for the first time.