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Abstract Epiphytes are considered indicators of forest ecological integrity, but the factors that explain their abundance are still not well understood. We here evaluated tree colonization by epiphytes in old-growth monospecific reforestation stands of Astronium urundeuva (M.Allemão) Engl. (Anacardiaceae) and Eucalyptus saligna Sm. (Myrtaceae), in comparison to a neighbor seasonal tropical forest fragment under similar environmental conditions. In each forest type, we identified and measured all trees (planted and colonizers) from 5-cm stem diameter in five 200 m² plots and quantified all vascular epiphytes per tree. Tree species were categorized by bark roughness, canopy deciduousness and growth rate. The abundance of epiphytes and the frequency of host trees were higher in the A. urundeuva plantation than in the native forest, with the E. saligna stand in an intermediate position. Also, we found that host traits influenced the abundance of epiphytes in their trunks. Host trees had average stem perimeter and height both higher than non-hosts, which indicates that colonization is more likely to occur in older trees. The average abundance of epiphytes per tree was higher in species with rough bark, but no relationship was found with canopy deciduousness or tree growth rate. We evidenced, therefore, that forest plantations, even if monospecific, can provide habitat for epiphytes. However, at community level, colonization success, either in native or restored forest, depends on the relative abundance of species whose bark type favors epiphytes establishment.

Resumo Epífitas são consideradas indicadores de integridade ecológica em florestas, mas os fatores que explicam sua abundância ainda não são bem compreendidos. Neste estudo, avaliamos a colonização por epífitas em antigos talhões monoespecíficos de Astronium urundeuva (M.Allemão) Engl. (Anacardiaceae) e Eucalyptus saligna Sm. (Myrtaceae), em comparação com um fragmento vizinho de floresta estacional semidecidual sob condições ambientais semelhantes. Em cada tipologia florestal, identificamos e medimos todas as árvores (plantadas e que colonizaram os locais) a partir de 5 cm de diâmetro à altura padrão, em cinco parcelas de 200 m². Nelas, também quantificamos todas as epífitas vasculares por árvore. Em busca de uma explicação funcional para as diferenças entre espécies, utilizamos rugosidade da casca, deciduidade da copa e taxa de crescimento como atributos potencialmente relevantes. A abundância das epífitas e a frequência de forófitos foi maior no talhão de A. urundeuva do que na floresta nativa, com o talhão de E. saligna ocupando uma posição intermediária. Encontramos evidências, também, de que os atributos dos forófitos influenciaram a abundância de epífitas em seus troncos. Os forófitos apresentaram maior perímetro médio e altura que as árvores não hospedeiras, o que indica que a colonização é mais provável de ocorrer em árvores mais velhas. A abundância média de epífitas por árvore foi maior em espécies com casca rugosa, mas nem a deciduidade da copa, nem a velocidade de crescimento exerceram efeito neste aspecto. Evidenciamos, portanto que, plantações florestais, ainda que monoespecíficas, podem prover habitat para epífitas. Contudo, em nível de comunidade, o sucesso da colonização, seja em florestas nativas ou restauradas, depende da abundância relativa de espécies cujo tipo de casca favorece o estabelecimento de epífitas.

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Mosquito blood feeding plays a key role in epidemiology. Despite its importance and large number of studies worldwide, less attention has been paid in South America. We summarized some general concepts and methodological issues related to the study of mosquito blood feeding habits, and compiled and analyzed all published information regarding the subject in the continent until 2020. Available literature comprised 152 scientific studies, that pursued different approaches: human landing catches (102 studies), baited trap (19), and blood meal analyses of collected specimens (38). Among the latter, 23 used serological and 15 molecular techniques. Species most frequently studied were those incriminated in malaria transmission, whereas relevant vectors such as Aedes aegypti, Ae. albopictus, and Haemagogus janthinomys were surprisingly neglected. Brazil was the leading country both in number of works and species studied. For over 70% of the species and three out of 13 South American countries there is no single information on mosquito blood feeding habits. Data from baited traps included 143 mosquito species, 83.9% of which were attracted to humans, either exclusively (10.5%) or in combination with other vertebrates (73.4%). Host blood identification of field collected specimens provided data on 102 mosquito species, and 60.8% of these fed on humans (55.9% combined with other vertebrates). Only 17 of the 73 species assessed by both methods yielded similar feeding patterns. Finally, supplementary tables are provided in a comprehensive summary of all information available and information gaps are highlighted for future research in the continent.

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Late blight disease, caused by the plant pathogen Phytophthora infestans, is one of the major threats for tomato and potato crops. Monitoring the populations of P. infestans is important to determine if there are changes in the sensitivity to fungicides and host preference. In this study, microsatellite markers and mitochondrial haplotypes were used to assess the genotype of isolates of P. infestans collected from tomato and potato plants in Colombia. Furthermore, sensitivity to the three fungicides cymoxanil (penetrant fungicide), mefenoxam, and fluopicolide (systemic fungicides), and tomato-potato host preference, were evaluated. Mitochondrial haplotyping showed that isolates collected on tomato were from the genetic groups Ia and Ib, while isolates collected on potatoes belonged to group IIa. Microsatellite analyses showed that isolates from tomato form two groups, including the Ib mitochondrial haplotype (which is genetically close to the US-1 clonal lineage) and the Ia haplotype (related to the EC-3 lineage), whereas Colombian isolates from potato formed a separate group. Furthermore, differences in sensitivity to fungicides were observed. Eighty-one percent of the isolates tested were resistant to mefenoxam with an EC50 >10 µg ml-1. Forty-two percent of the isolates showed an intermediate resistance to cymoxanil. The EC50 values ranged between 1 and 10 µg ml-1. For fluopicolide, 90% of the isolates were sensitive, with EC50 <1 µg ml-1. Host preference assays showed that potato isolates infected both host species. Thus, isolates that infect potatoes may pose a risk for tomato crops nearby.

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The transmission of pathogens that cause leishmaniases occurs by the bite of female sand flies (Diptera: Psychodidae) in their vertebrate hosts, which makes the identification of their bloodmeal sources an important step for the control and epidemiology of these diseases. In Brazil, the state of Roraima has a great diversity of sand flies, vertebrate hosts, and protozoan Leishmania, but little is known about the host blood-feeding preferences of sand flies. Thus, we evaluated the bloodmeal sources of sand flies collected from their sylvatic habitats in Parque Nacional do Viruá, Roraima. Fieldwork was carried-out between 13th and 18th August 2019 using CDC light traps. Sand flies were slide-mounted and morphologically identified using the head and last segments of the abdomen. Engorged females had their DNA extracted, followed by amplification and sequencing of the cytochrome b (cytb) molecular marker for vertebrates. Sequences were analyzed and compared with those from GenBank using the BLASTn search tool, in addition to the reconstruction of a phylogenetic tree to demonstrate the clustering pattern of these sequences. A total of 1,209 sand flies were identified, comprising 20 species, in which the most abundant were Psychodopygus ayrozai (Barretto and Coutinho) (42.10%) and Psychodopygus chagasi (Costa Lima) (26.22%). Bloodmeal source identification was successfully performed for 34 sand flies, that confirm four vertebrate species, being the most abundant the armadillo Dasypus novemcinctus Linnaeus, 1758 (Cingulata: Dasypodidae).

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Recently commenced host-parasite interactions provide an excellent opportunity to study co-evolutionary processes. Multi-host systems are especially informative because variation in virulence between hosts and temporal changes provides insight into evolutionary dynamics. However, empirical data under natural conditions are scarce. In the present study, we investigated the interaction between Darwin's finches and the invasive fly Philornis downsi whose larvae feed on the blood of nestlings. Recently, however, the fly has changed its behavior and now also attacks incubating females. Two sympatric hosts are affected differently by the parasite and parasite load has changed over time. Our study observed a reversal of trends described two decades ago: while, currently, small tree finches (Camarhynchus parvulus) experience significantly higher parasite load than warbler finches (Certhidea olivacea), this was the opposite two decades ago. Currently, fledging success is higher in warbler finches compared to small tree finches. Our data indicate that not only intensity but also timing of infestation influences hosts' reproductive success and parasite fitness. During incubation, prevalence was higher in warbler finches, but once chicks had hatched, prevalence was 100% in both species and parasite load was higher in small tree finches. Furthermore, our results suggest faster development and higher reproductive success of P. downsi in small tree finch nests. A change in host preference driven by larvae competition could have led to the reversal in parasite load.

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ABSTRACT We report for the first time field infestation under natural conditions by Anastrepha bahiensis on star fruit (Averrhoa carambola L., Oxalidaceae) in the state of Pará, Eastern Amazon, Brazil. This report reinforces the importance of field infestation studies on fruit flies in the Brazilian Amazon.

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Oviposition substrate selection, egg mass characteristics, host preference, and life history of Lycorma delicatula (White) (Hemiptera: Fulgoridae) were studied in Pennsylvania between 2016 and 2017. Twenty-four substrate types (trees, shrubs, and nonliving materials) were selected by females for oviposition. Tree-of-heaven, black cherry, black birch, and sweet cherry were favored at 62.5% of the types and accounted for 68.5% of the egg masses based on survey results 200 cm above ground. Egg mass density ranged between 0.2 and 75.2 egg masses/m2 with no significant difference among substrate types. Egg mass size ranged between 0 and 192 eggs/egg mass, with 91.8% containing <50 eggs. Significantly larger egg masses were found on sweet and black cherry compared with tree-of-heaven, with significantly higher hatch success on black locust. Eggs hatched between May 2 and June 5 and peaked on 18 May 2017. Tree-of-heaven and summer grape were preferred by nymphs and adults, while multiflora rose and black walnut were favored by the first, second, and the fourth instar nymphs, respectively. The first, second, third, fourth instars and adults lasted for 62 (2 May-3 July), 42 (8 June-20 July), 35 (26 June-31 July), 39 (10 July-18 Aug.), and 114 (24 July-15 Nov.) days, with peaks on 25 May, 22 June, 6 July, 31 July, and 22 Aug., respectively. Adult feed for 2 months before laying eggs in early October. Cumulative degree-days were 0-325, 153-652, 340-881, 567-1,020, 738-1,227, and 942-1,795 for the egg, first, second, third, fourth instar, and adult stage, respectively. Oviposition strategies and development patterns were discussed.

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Mexican bean beetle, Epilachna varivestis Mulsant (Coleoptera: Coccinellidae), is a serious pest of snap bean, Phaseolus vulgaris L. (Fabales: Fabaceae), lima bean, Phaseolus lunatus L. (Fabales: Fabaceae), and an occasional pest of soybean, Glycine max (L.) Merr. (Fabales: Fabaceae), in the United States. Past research indicates that some bean cultivars endure greater injury from this pest than others, suggesting that such crops are either more preferred, better hosts, and/or have poorer defenses. This study characterizes injury potential among three snap bean and three lima bean cultivars by measuring ovipositional preference, survival, and feeding injury of E. varivestis in field and greenhouse experiments. Snap beans, as a group, were more preferred and susceptible to injury than lima beans. The purple wax snap bean, Dragon's Tongue, was the most susceptible overall; while the dwarf bush lima bean, Henderson, was the least susceptible. The results of this study will aid in the development of integrated pest management strategies for E. varivestis, while also providing broader biological information for future research on this pest and others.

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Seed depredation is recognized as a determining factor in plant community structure and composition. Ants are primary consumers of seeds influencing abundance of epiphytes on trees. This study was conducted in two subunits of a tropical dry forest established on different soil substrates in San Andrés de la Cal, Tepoztlán, in Morelos, Mexico, and experimentally tested whether seed removal activity is higher in tree species with smaller epiphyte loads compared to those with greater epiphyte loads. Five trees were selected at random from six species of trees with high (preferred hosts) or low (limiting hosts) epiphyte loads. Seed removal differed among hosts and different soil substrates in the forest. On relating seed removal to the abundance of arboreal ants, the most consistent pattern was that lower seed removal was related to lower ant abundance, while high seed removal was associated with intermediate to high ant abundance. Epiphyte seed removal by ants influences epiphyte abundance and can contribute considerably to a failure to establish, since it diminishes the quantity of seeds available for germination and establishment.

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Human commerce has resulted in the spread of the imported fire ants, Solenopsis species, worldwide. Six species of parasitic Pseudacteon phorid flies that are highly host specific to the Solenopsis saevissima complex of Solenopsis fire ants have been successfully released in the southern United States. The presence of Pseudacteon phorid flies, in addition to having direct mortality effects on their host ants, modifies foraging behavior and disrupts interspecific competition between host species and other ant species in the community. Fire ant workers have evolved effective methods to cope with parasitism pressure, which may relieve population-level impacts of introduced phorid flies. This review focuses on the mechanisms underlying host location, host preference, and host-size selection of Pseudacteon phorid flies and highlights their direct and indirect effects on fire ant populations. Knowledge gained from parasitoid-ant interactions will enhance use of natural enemies as biological control agents for invasive social insects.

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The aim of the present study was to investigate the parasitism of two fruit fly species by different Diachasmimorpha longicaudata strains. Females of two parasitoid strains were reared on Ceratitis capitata or Anastrepha fraterculus that were conditioned in adapted containers. Individual parasitoids were offered 20 larvae for 1 h, using no-choice (20 C. capitata or 20 A. fraterculus) or free-choice (10 of each species) assays. Parasitism was verified by counting scars, and the pupae were classified as non-parasitized (no scars), parasitized (one scar), or superparasitized (multiple scars). Parasitism intensity was compared by evaluating the proportions of non-parasitized, parasitized, and superparasitized larvae. Parasitism intensity and scar frequency were analyzed as functions of host species and parasitoid strain, using chi-square tests. In the non-choice tests, females of both parasitoid strains parasitized the larvae, regardless of host species. However, when the parasitoids had a choice, they preferred to superparasitize A. fraterculus larvae, which are larger than C. capitata larvae. In addition, the female parasitoids parasitized most of the host larvae, regardless of parasitoid strain or host species. However, the frequency of non-parasitized pupae was higher when the offered host species was different from the one in which the parasitoid was reared, and the frequency of superparasitized pupae was higher when the offered host species was the same as the one in which the parasitoid was reared.(AU)

O objetivo deste trabalho foi avaliar o parasitismo de larvas de Tephritidae por duas linhagens de Diachasmimorpha ­longicaudata em duas espécies de mosca-das-frutas. Foram utilizadas fêmeas do parasitoide criadas sobre Ceratitis capitata ou Anastrepha fraterculus acondicionadas em gaiolas adaptadas. Para cada fêmea foram oferecidas 20 larvas durante 1 hora, em ensaio com chance de escolha (20 C. capitata ou 20 A. fraterculus) e sem chance de escolha (10 larvas de cada espécie). Após o parasitismo, o número de cicatrizes foi verificado e os pupários classificados como: não parasitados (ausência de cicatrizes), parasitados (presença de uma cicatriz) e superparasitados (duas ou mais cicatrizes). A intensidade de parasitismo foi avaliada por meio da proporção de larvas não parasitadas, parasitadas ou superparasitadas. As variáveis intensidade de parasitismo e frequência de cicatrizes em virtude do hospedeiro e da linhagem do parasitoide foram analisadas quanto à distribuição de frequência utilizando-se o teste qui-quadrado. No teste sem escolha, independentemente da espécie hospedeira, as fêmeas das duas linhagens parasitaram as larvas oferecidas e, quando tiveram escolha, preferiram superparasitar larvas de A. fraterculus, que são maiores que as de C. capitata. A frequência de pupários sem cicatriz foi maior quando o hospedeiro oferecido foi diferente daquele em que a fêmea foi criada. Independentemente da linhagem do parasitoide, as fêmeas parasitam a maioria das larvas hospedeiras das duas espécies, mas discriminam o hospedeiro, preferindo superparasitar a espécie na qual foi criada o hospedeiro. A. fraterculus foi o preferido para postura de fêmeas.(AU)

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The aim of the present study was to investigate the parasitism of two fruit fly species by different Diachasmimorpha longicaudata strains. Females of two parasitoid strains were reared on Ceratitis capitata or Anastrepha fraterculus that were conditioned in adapted containers. Individual parasitoids were offered 20 larvae for 1 h, using no-choice (20 C. capitata or 20 A. fraterculus) or free-choice (10 of each species) assays. Parasitism was verified by counting scars, and the pupae were classified as non-parasitized (no scars), parasitized (one scar), or superparasitized (multiple scars). Parasitism intensity was compared by evaluating the proportions of non-parasitized, parasitized, and superparasitized larvae. Parasitism intensity and scar frequency were analyzed as functions of host species and parasitoid strain, using chi-square tests. In the non-choice tests, females of both parasitoid strains parasitized the larvae, regardless of host species. However, when the parasitoids had a choice, they preferred to superparasitize A. fraterculus larvae, which are larger than C. capitata larvae. In addition, the female parasitoids parasitized most of the host larvae, regardless of parasitoid strain or host species. However, the frequency of non-parasitized pupae was higher when the offered host species was different from the one in which the parasitoid was reared, and the frequency of superparasitized pupae was higher when the offered host species was the same as the one in which the parasitoid was reared.(AU)

O objetivo deste trabalho foi avaliar o parasitismo de larvas de Tephritidae por duas linhagens de Diachasmimorpha ­longicaudata em duas espécies de mosca-das-frutas. Foram utilizadas fêmeas do parasitoide criadas sobre Ceratitis capitata ou Anastrepha fraterculus acondicionadas em gaiolas adaptadas. Para cada fêmea foram oferecidas 20 larvas durante 1 hora, em ensaio com chance de escolha (20 C. capitata ou 20 A. fraterculus) e sem chance de escolha (10 larvas de cada espécie). Após o parasitismo, o número de cicatrizes foi verificado e os pupários classificados como: não parasitados (ausência de cicatrizes), parasitados (presença de uma cicatriz) e superparasitados (duas ou mais cicatrizes). A intensidade de parasitismo foi avaliada por meio da proporção de larvas não parasitadas, parasitadas ou superparasitadas. As variáveis intensidade de parasitismo e frequência de cicatrizes em virtude do hospedeiro e da linhagem do parasitoide foram analisadas quanto à distribuição de frequência utilizando-se o teste qui-quadrado. No teste sem escolha, independentemente da espécie hospedeira, as fêmeas das duas linhagens parasitaram as larvas oferecidas e, quando tiveram escolha, preferiram superparasitar larvas de A. fraterculus, que são maiores que as de C. capitata. A frequência de pupários sem cicatriz foi maior quando o hospedeiro oferecido foi diferente daquele em que a fêmea foi criada. Independentemente da linhagem do parasitoide, as fêmeas parasitam a maioria das larvas hospedeiras das duas espécies, mas discriminam o hospedeiro, preferindo superparasitar a espécie na qual foi criada o hospedeiro. A. fraterculus foi o preferido para postura de fêmeas.(AU)

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Harmonia axyridis (Pallas, 1773) is an Asian coccinellid released in several places to act as a biological control agent of aphids. Dinocampus coccinellae (Schrank, 1802) is an endoparasite that uses more than 40 coccinellid species as hosts. Thus, the aim of this study was to investigate the interactions between D. coccinellae and H. axyridis and to determine the impact of the parasitoid on the establishment capacity of H. axyridis It was also investigate the influence of host on the development of D. coccinellae using other Coccinellidae species as hosts: Cycloneda sanguinea, (L., 1763) Cycloneda pulchella (Klug, 1829), Eriopis connexa (Germar, 1824), and Olla v-nigrum (Mulsant, 1866) In no-choice tests, pupa was the least attacked stage, and the fourth instar and adults the most attacked. In choice tests, the pupa was less attacked when combined with all the other stages, and the fourth instar and adults the most attacked. There was statistical difference only for fecundity, fertility, and number of eggs/day, with higher values found in the non-parasitized control group. Due to the low rate of parasitism it is believed that D. coccinellae has little impact on the populations of this coccinellid in Brazil. However, it is noteworthy that an increase in H. axyridis coverage areas can affect the populations of D. coccinellae, as in some places of occurrence, H. axyridis has become the predominant species of Coccinellidae. The result can be a decrease in populations of this species of parasitoid or its better adaptation to the new host.

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Epiphytes are strongly dependent on the conditions created by their host's traits and a certain degree of specificity is expected between them, even if these species are largely abundant in a series of tree hosts of a given environment, as in the case of atmospheric bromeliads. Despite their considerable abundance in these environments, we hypothesize that stochasticity alone cannot explain the presence and abundance of atmospheric bromeliads on host trees, since host traits could have a greater influence on the establishment of these bromeliads. We used secondary and reforested seasonal forests and three distinct silvicultures to test whether species richness, phylogenetic diversity and functional diversity of trees can predict the differential presence, abundance and distribution of atmospheric bromeliads on hosts. We compared the observed parameters of their assemblage with null models and performed successive variance hierarchic partitions of abundance and distribution of the assemblage to detect the influence of multiple traits of the tree hosts. Our results do not indicate direct relationships between the abundance of atmospheric bromeliads and phylogenetic or functional diversity of trees, but instead indicate that bromeliads occurred on fewer tree species than expected by chance. We distinguished functional tree patterns that can improve or reduce the abundance of atmospheric bromeliads, and change their distribution on branches and trunk. While individual tree traits are related to increased abundance, species traits are related to the canopy distribution of atmospheric bromeliad assemblages. A balance among these tree functional patterns drives the atmospheric bromeliad assemblage of the forest patches.

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Parasites can invade new ecosystems if they are introduced with their native hosts or if they successfully infect and colonise new hosts upon arrival. Here, we ask to what extent an introduced parasite demonstrates specialisation among novel host species. Infection surveys across three field sites in Gatun Lake, Panama, revealed that the invasive peacock bass, Cichla monoculus, was more commonly infected by the introduced trematode parasite Centrocestus formosanus than were three other common cichlid fishes. Laboratory infection experiments were conducted to determine whether parasitism might be driven by differential encounter/exposure to parasites or by differential infection susceptibility/preference across different host species. These experiments were performed by controlling for parasite exposure in single host (compatibility) experiments and in mixed host (preference) experiments. In all cases, the peacock bass exhibited higher infection rates with viable metacercariae relative to the other potential fish hosts. Our experiments thus support that an introduced generalist parasite shows apparent specialisation on a specific novel host. Further studies are needed to determine whether these patterns of specialisation are the result of local adaptation following invasion by the parasite.

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Melipona eburnea Friese is a stingless bee kept in some regions of Colombia, where it is reported to be vulnerable to extinction due to habitat disturbance. To contribute to raising conservation strategies, the aim of this study was to identify the floral preferences of this species using melissopalynological analysis. A total of 31 pollen pot samples and 37 honey samples were taken from March 2009 through March 2010 from four colonies in Fusagasuga, Colombia. We found 92 pollen types: 17 from pollen pot samples, 39 from honey samples (indicating the sources of nectar), and 36 in both types of samples. The most frequent pollen types in the pollen pot samples were Myrcia type (100%), Eucalyptus globulus (96.9%), and Fraxinus uhdei (96.9%). The most frequent pollen types in honey samples were E. globulus (97.4%) and Myrcia type (94.9%). The pollen types corresponded mainly to native plants (68%), trees (44.5%), plants whose sexual system is hermaphroditic (56.5%), and plants with inflorescences (76.2%). The most frequent shapes of the flowers were brush-like (type Myrtaceae) and dish-like (type Asteraceae), and the preferred flower colors were white or cream (52.2%). In general, we found that M. eburnea showed a strong preference for trees of the family Myrtaceae to obtain nectar and pollen, including native and introduced species. Some other families are contributing significantly, such as Melastomataceae for pollen collection and Asteraceae for nectar. These results highlight the key plant species for the diet of M. eburnea.

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The study was carried out in a 3 000m2 area of coastal Atlantic rain forest at Ilha do Mel island (25o30’’S 48o23’W), on 100 assorted trees separated into 2 meter-high strata starting from the ground. In each stratum all of the occurring epiphytic species were recorded. The sampled species were grouped into three categories: exclusive, preferential, and indifferent, according to their abundance in each strata, and selective, preferential and indifferent, according to abundance on the forophytes. Intermediate strata registered the highest diversity. Six species were considered exclusive to one or two strata, 15 were restricted to some strata and 5 presented a broad distribution. No epiphytic species showed uniform horizontal distribution on the area. The epiphyte richness in a host tree varied from zero to 30. Regarding to fidelity on host tree species, few selective or preferential, and mainly indifferent epiphyte species, were found. A total of 82 epiphyte species were sampled in the surveyed tree, and the Wittaker plot indicate a highly dominant assemblage. Rev. Biol. Trop. 57 (3): 749-759. Epub 2009 September 30.

El estudio se realizó en un área 3 000 m2 de bosque atlántico húmedo en una isla brasileña, Ilha do Mel (25o30’’ S 48o23’ W). Seleccionamos 100 árboles de las 10 principales especies y las dividimos en estratos de dos metros a partir de la superficie del suelo. En cada estrato registramos todas las especies epífitas observadas. Las especies muestreadas fueron agrupadas en tres categorías: exclusivas, preferenciales, e indiferentes (según su abundancia en los estratos), y selectivas, preferenciales e indiferentes (según su abundancia en los árboles). Los estratos intermedios registraron las más altas diversidades. Seis especies fueron consideradas exclusivas a uno o dos estratos, 15 estuvieron limitadas a algunos estratos y 5 presentaron amplia distribución. Para ninguna especie epífita hubo distribución horizontal uniforme. La riqueza de las epífitas en un forofito varió de cero a 30 especies. Según la fidelidad de las epífitas en los árboles, registramos pocas especies selectivas o preferenciales y muchas indiferentes. En los 100 árboles examinados encontramos 82 especies de epífitas, y el diagrama del Wittaker indicó alta dominancia de unas pocas especies.

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ABSTRACT Microtheca punctigera (Achard) (Coleoptera: Chrysomelidae) is a major pest of Brassicaceae family plants in Brazil and occurs together with M. semilaevis. Occurrence of larvae and adults of M. punctigera and M. semilaevis Stal in five host plants grown in closely patchs was investigated in three periods in the field [Fall/Winter 2001 (May 10 to July 21); Fall 2002 (April 3 to June 12), and Spring 2002 (September 20 to November 15)]. Treatments were Chinese cabbage, mustard, watercress, arrugula and radish. The standard of occurrences of larvae of M. punctigera + M. semialevis was not repeated in the three trials: Chinese and mustard were the preferred food in 2001 Fall Winter while in the 2002 Fall and 2002 Spring preference was predominated for mustard and arrugula. M. punctigera was the predominant species during the experiments and populations were higher in the winter periods. In general, M. punctigera beetles were found mostly on Chinese cabbage and mustard, but in some assessments populations were high also in other hosts (mostly arugula). M. semialevis beetles occurred mostly on Chinese cabbage and mustard.

RESUMO Microtheca punctigera (Achard) é praga primária de plantas da família Brassicaceae no Brasil e ocorre associada com M. semilaevis Stal. Ocorrência de larvas e adultos de M. punctigera e M. semilaevis em cinco plantas hospedeiras em parcelas próximas foi avaliada em três períodos no campo ([outono/inverno, 2001 (10 de maio a 21 de julho); outono, 2002 (3 de abril a 12 de junho), e primavera, 2002 (20 de setembro a 15 de novembro)]. Os tratamentos foram couve chinesa, mostarda, agrião, rúcula e rabanete. O padrão de ocorrência de larva de M. punctigera + M. semialevis não se repetiu nos três períodos de avaliação: couve chinese e mostarda foram os alimentos preferidos no outono/inverno de 2001, enquanto que no outono e primavera de 2002, mostarda e rúcula foram os hospedeiros preferidos.M. punctigera foi a espécie predominante durante os experimentos e as populações foram maiores no período de inverno. De maneira geral, besouros de M. semialevis foram encontrados principalmente em couve chinesa e mostarda, mas em algumas as avaliações populações foram superiores em outros hospedeiros (principalmente em rúcula). Besouros de M. semialevis ocorreram principalmente em couve chinesa e mostarda.

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O estudo dos hábitos alimentares e do conteúdo intestinal dos flebotomíneos permite a identificação dos hospedeiros, indicando os potenciais reservatórios das leishmanias. Este trabalho objetivou determinar a preferência alimentar de Lutzomyia longipalpis e sua relação com a transmissão da leishmaniose visceral. As capturas mensais foram realizadas em área de transmissão de leishmaniose visceral, município de Várzea Grande, Estado de Mato Grosso, no período de janeiro de 2004 a junho de 2006, utilizando-se armadilhas de luz CDC. Foram capturadas 2.376 fêmeas de Lutzomyia longipalpis, das quais 104 (4,4 por cento) estavam ingurgitadas, sendo 32 (30,8 por cento) capturadas no intradomicílio e 72 (69,2 por cento) no peridomicílio. Após reação de precipitina, observou-se que as fêmeas de Lutzomyia longipalpis alimentaram-se preferencialmente em aves (30,8 por cento) e roedores (21,2 por cento), mas também foram encontradas fêmeas alimentadas de sangue de humanos, gambás, bois, cavalos e cães, demonstrando o caráter oportunista da espécie.

Studies on the feeding habits and intestinal content of sandflies make it possible to identify hosts, thereby indicating potential reservoirs for Leishmania. The present study had the aim of determining the feeding preferences of Lutzomyia longipalpis and its relationship with the transmission of visceral leishmaniasis. Specimens were caught every month in a transmission area of visceral leishmaniasis, in the municipality of Várzea Grande, State of Mato Grosso, from January 2004 to June 2006, using CDC light traps. 2,376 females of Lutzomyia longipalpis were caught, of which 104 (4.4 percent) were engorged. Among these, 32 (30.8 percent) were caught inside homes and 72 (69.2 percent) in areas surrounding homes. From the precipitin reaction, it was observed that Lutzomyia longipalpis females fed preferentially on birds (30.8 percent) and rodents (21.2 percent), but they were also found to have fed on blood from humans, opossums, oxen, horses and dogs, thus demonstrating the opportunist nature of this species.

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