Plant inhabiting mites (Acari) from the Cerrado biome of Mato Grosso State, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A new Hemigrammus Gill from upper rio Parana system, Southeastern Brazil (Characiformes : Characidae)

Hemigrammus parana is described from the upper rio Parana system, in the area of influence of the Ilha Solteira reservoir in states of Mato Grosso do Sul, Minas Gerais and São Paulo, southeastern Brazil. The new species differs from all congeners by the combination of the following characters: absence of humeral spot; presence of a roughly triangular or rectangular conspicuous black caudal spot, extending from base to tip of middle caudal-fin rays, its greatest depth at base of caudal-fin rays; and anal-fin rays iii-iv, 18-23.

Spatial and temporal distribution of the zoobenthos community during the filling up period of Porto Primavera Reservoir (Paraná River, Brazil)

Este estudo é parte do monitoramento limnológico empreendido pela Companhia Energética do Estado de São Paulo (CESP) durante o processo de enchimento do reservatório de Porto Primavera (Usina Hidrelétrica Engenheiro Sérgio Motta). Este reservatório, localizado no alto rio Paraná, entre os Estados de São Paulo e Mato Grosso, é o quarto maior do país. A primeira etapa de enchimento do lago começou em dezembro de 1998 e a segunda em março de 2001. Amostras para a análise da comunidade bentônica e das características sedimentológicas foram coletadas trimestralmente entre agosto de 1999 e novembro de 2001 e também em agosto de 2002 (11 campanhas). As coletas foram feitas em 13 estações de amostragem distribuídas no reservatório e em uma localizada a jusante da barragem. 128 táxons de invertebrados foram encontrados, sendo Mollusca, Annelida, Insecta e Nematoda os grupos dominantes durante praticamente todos os meses analisados. A classe Insecta foi a melhor representada, com 9 diferentes ordens, dentro das quais os Diptera contribuíram com a ocorrência de 63 táxons. A espécie exótica de bivalve Corbicula fluminea foi registrada em todas as estações de amostragem mostrando sua grande capacidade para colonizar novos habitats em regiões neotropicais. Variações consideráveis na densidade da fauna foram observadas para os diferentes períodos e locais analisados. A densidade máxima (média de 7812 ind.m-2) foi registrada no centro do reservatório enquanto que as densidades mínimas foram registradas na zona lacustre próxima à barragem (média de 9 ind.m-2). A maior riqueza de espécies por local/período (24 táxons) foi encontrada no trecho superior do reservatório (trecho fluvial). A diversidade máxima foi observada nas zonas superior e central do reservatório, com valores de 3.82 e 3.86 (bits.ind-1) no início (agosto/1999) e final (agosto/2002) do processo de enchimento, respectivamente. Não foi encontrado um padrão de distribuição dos grupos faunísticos que pudesse estar associado com a textura granulométrica dos diferentes locais amostrados. Por outro lado, constatou-se a diminuição, ou mesmo a não ocorrência de organismos, nas estações com elevada concentração de matéria orgânica (>40%) em baixo estado de degradação (grandes detritos vegetais). Tal fato pode estar relacionado com a falta de depósitos de sedimentos, dificultando a fixação de organismos da fauna bentônica, bem como com condições químicas mais redutoras em função da intensidade dos processos de decomposição da fitomassa inundada.

Recursos alimentares explorados pelos cupins (Insecta: Isoptera)

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

Prevalence of larvae of the bot fly Cuterebra simulans (Diptera, Oestridae) on Gracilinanus microtarsus (Didelphimorphia, Didelphidae) in southeastern Cerrado from Brazil

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

Morcegos cavernícolas da região do Distrito Federal, centro-oeste do Brasil (Mammalia, Chiroptera)

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

Distribuição vertical, danos e controle cultural de Stenoma catenifer Walsingham (Lepidoptera: Elachistidae) em pomar de abacate

Stenoma catenifer Walsingham is the major pest in avocado groves (Persea americana Mill.) in the Neotropical region. Management has been difficult for many reasons related to the reduced knowledge on its bioecology and the avocado growing systems. The goal of this work was to study the vertical distribution of S. catenifer in avocado plants, the gagging effect of infested fruit on its survival, and the losses caused. The experiments were conducted in a commercial grove located at the Sao Tomas de Aquino, State of Minas Gerais, Brazil, during the 2001/2002 and 2002/2003 growing season. S. catenifer was observed especially at the lower and central part of the plant, and the inner canopy was the least attacked in comparison with the north, south, east and west quadrants. These results may be important indicators for the use of am adequate sampling procedure. The highest percentage of attacked fruit had one to four larvae; in some cases up to eight individuals per fruit were found. The losses caused by the borer varied during the agricultural season, with figures close to 5% in a single evaluation, and the harvest loss may reach 27%. The bagging of infested fruit caused mortality of S. catenifer, as observed through the evaluation carried out four days later.

Four new species of Bacilloflagellomera Papp & Silva, 1995 (Diptera, Lauxaniidae)

Four new species of the Neotropical Lauxaniidae genus Bacilloflagellomera Papp & Silva, 1995 (Diptera, Lauxaniidae) from Brazil are described: B. flava sp. n, (Para, Belem); B. fusca sp. n. (São Paulo, Aracatuba), B. longicornus sp. n. (Amapa, Serra do Navio) and B. nigrifemuris sp. n. (Para, Belem). A key for the identification of the species, illustrations of head, wing and terminalia of the new species are provided. A short discussion on the structure and systematic value of the inner morphology of female terminalia is included.

Cytogenetics of three Brazilian Goniosoma species: A new record for diploid number in Laniatores (Opiliones, Gonyleptidae, Goniosomatinae)

Currently, 60 species of harvestmen have been karyotyped and all of these are from the Nearctic and Palearctic regions. This work is the first cytogenetic report of three gonyleptid species of the suborder Laniatores: Goniosoina aff. badiuln, G. proxiinuni and G. spelaeum of the Neotropical region, from the southeastern region of Brazil. Conventional Giemsa stain chromosome preparations were obtained from embryonic cells and adult male testes. Embryo mitotic plates of G. aff. badium and G. proximum indicated 88 chromosomes, and mitotic spermatogonial plates of G. spelaeum males revealed intra- and interindividual variation of chromosome number, ranging from 92-109 chromosomes. In the three analyzed species, the mitotic chromosomes were meta- or subinetacentric with no obvious sex chromosomes being identified during mitosis. Prophase I spermatocytes of G. spelaeum also revealed intra- and interindividual bivalent number variation and furthermore indicated the presence of multivalence. The karyotypes of these three Goniosoina species exhibited the largest chromosome pair with a negative heteropycnosis in the distal region of the shortest arrn chromosomes of G. spelaeum submitted to silver impregnation evidenced this negative heteropycnotic region as nucleolus organizer region (NOR). These results, when compared with cytogenetic data of other Laniatores species from the Palearctic region, indicated that a new record for diploid chromosome number probably characterize the genus Goniosoma in the Neotropical region.

Breeding of the Scuttle Fly Megaselia scalaris in a fish Carcass and Implications for the use in Forensic Entomology (Diptera: Phoridae).

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

Utilization of epiphytes by birds in a Brazilian Atlantic Forest

Epiphytes constitute a great part of the vegetation biomass in Neotropical forests, offering a large variety of resources to birds. Despite their structural and ecological importance, few studies investigated the use of epiphytes by birds in the Neotropical region. We studied the bird species that exploit vascular epiphytes (and hemi-epiphytes) in an Atlantic forest site in southeastern Brazil. The resources exploited, seasonal variation in the use of epiphytes, the frequency of foraging and selectivity in epiphytes, and the relationship between the use of epiphytes and the participation in mixed-species bird flocks were investigated. After 360 h of observations along trails crossing the forest, 24 bird species (12 families) were recorded in a total of 74 events of epiphyte exploitation. Thamnophilidae (four species), Trochiliclae, Thraupidae and Furnariidae (three species) were the richest bird families in our sample, while Furnariidae and Dendrocolaptidae were the more frequently recorded families. Plants in the Bromeliaceae and Araceae families were the most abundant and more frequently exploited epiphytes. Nectar, water, nest material and invertebrates were the most frequently exploited resources, mainly from Bromeliaceae. None of the species for which we had enough data revealed to be a frequent user of epiphytes for foraging or selective to any epiphyte group. The White-eyed Foliage-gleaner (Automolus leucophthalmus; Furnariidae), a common participant of understory mixed-species flocks, exploited epiphytes more frequently when associated with mixed-species flocks. The utilization of epiphytes was opportunistic for most of the bird species recorded and occurred throughout the year with no seasonal variation.

Plant glandular trichomes mediate protective mutualism in a spider-plant system

1. Although several species of Peucetia (Oxyopidae) live strictly in association with plants bearing glandular trichomes worldwide, to date little is known about whether these associations are mutualistic.2. In this study we manipulated the presence of Peucetia flava on the glandular plant Rhynchanthera dichotoma in the rainy and post-rain season, to test the strength of its effects on leaf, bud, and flower damage and plant reproductive output. In addition, we ran independent field experiments to examine whether these sticky structures improve spider fidelity to plants.3. Peucetia suppressed some species of foliar phytophages, but not others. Although spiders have reduced levels of leaf herbivory, this phenomenon was temporally conditional, i.e. occurred only in the post-rain but not in the rainy season. Floral herbivory was also reduced in the presence of spiders, but these predators did not affect plant fitness components.4. Plants that had their glandular trichomes removed retained fewer insects than those bearing such structures. Spiders remained longer on plants with glandular trichomes than on plants in which these structures had been removed. Isotopic analyses showed that spiders that fed on live and dead labelled flies adhered to the glandular hairs in similar proportions.5. Spiders incurred no costs to the plants, but can potentially increase individual plant fitness by reducing damage to reproductive tissues. Temporal conditionality probably occurred because plant productivity exceeded herbivore consumption, thus dampening top-down effects. Specialisation to live on glandular plants may have favoured scavenging behaviour in Peucetia, possibly an adaptation to periods of food scarcity.

Amblyomma cajennense ticks induce immediate hypersensitivity in horses and donkeys

Since host immune reaction to ticks interferes with tick-borne pathogen transmission, it is important to recognize naturally occurring tick-host immune relationships to better understand the epidemiology of such infectious diseases. Amblyomma cajennense is an important tick-borne disease vector in the Neotropical region and horses maintain it in domestic environments. In the present work intradermal testing of A. cajennense tick exposed horses and donkeys using crude tick antigens was used to evaluate the type of hypersensitivity induced by infestations. Animals sensitized by A. cajennense infestation displayed an immediate hypersensitivity reaction at the antigen inoculation site. Foals sensitized with experimental infestations and field sensitized horses presented the most intense reactions (40% of ear thickness increase). Field sensitized donkeys presented less intense reaction reaching no more than 22% of mean thickness increase. Control horses (non-sensitized) had the least intense reaction, with a peak of no more 12% of increase. The presence of a prominent immediate hypersensitivity in equids sensitized experimentally or by field infestations indicates that A. cajennense ticks induce in this host an immune response that is associated with IgE production and which is known to be inappropriate against intracellular pathogens. Differences observed between horses and donkeys are discussed.

Cloning and characterization of the cDNA for the Brazilian Cratomorphus distinctus larval firefly luciferase: Similarities with European Lampyris noctiluca and Asiatic Pyrocoelia luciferases

Studies on firefly (Lampyridae) luciferases have focused on nearctic species of Photinus and Photuris and Euroasiatic species of Lampyris, Luciola, Hotaria, and Pyrocoelia. Despite accounting for the greatest diversity of fireflies in the world, no molecular studies have been carried out on the highly diverse genera from the neotropical region. Here we report the luciferase cDNA cloning for the larva of the Brazilian firefly Cratomorphus distinctus. The cDNA has 1978 bp and codes for a 547-residue-long polypeptide. Noteworthy, sequence comparison as well as functional properties show the highest degree of similarity with Lampyris noctiluca (93%) and Pyrocoelia spp. (91%) luciferases, suggesting a close phylogenetic relationship despite the geographical distance separating these species. The bioluminescence emission spectrum peaks at 550 nm and, as expected, is sensitive to pH, shifting to 605 nm at pH 6. The kinetic properties of the recombinant luciferase were similar to those of other firefly luciferases. © 2004 Elsevier Inc. All rights reserved.

Corumbataia britskii (Siluriformes: Loricariidae: Hypoptopomatinae) a new species from the upper Rio Paraná basin, Mato Grosso do Sul, Central Brazil

A new Hypoptopomatinae, Corumbataia britskii, is described based on specimens recently collected in a tributary of the upper Rio Paraná basin, Mato Grosso do Sul State, Brazil. Corumbataia britskii differs from its congeners by having a more depressed head profile (vs. a more rounded head profile in C. cuestae and C. tocantinensis), by having a more developed and conspicuous tuft of enlarged odontodes on the tip of the supraoccipital (vs. its reduced condition found in C. cuestae and C. tocantinensis), and by heaving a partially enclosed arrector fossae (vs. an almost completely enclosed arrector fossae in C. cuestae and C. tocantinensis). Copyright © 2007 Magnolia Press.