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

The prevalence of Cuterebra simulans bot fly parasitism on marsupial Gracilinanus microtarsus was compared between sexes and seasons of the year. No significant difference was observed between females and males but prevalence was higher in warm-wet season than cool-dry season. This pattern agree with observations of others studies with oestrids flies in southern Neotropical areas, suggesting the occurrence of latitudinal change in the peak of bot flies reproductive activity related to seasons of the year along these systems. This is the first record of C. simulans larvae parasitism on G. microtarsus and its occurrence in southern areas of the Neotropical region.

Efeito de extratos de plantas do Cerrado em Dipetalogaster maxima (Uhler) (Hemiptera, Reduviidae)

A transmissão da doença de Chagas ocorre, principalmente, por meio de fezes de hemípteros hematófagos (Triatominae), os quais ingerem o Trypanosoma cruzi ao se alimentarem do sangue de pessoas ou outros mamíferos infectados. Para o controle dos triatomíneos, os piretróides são os principais inseticidas utilizados. Entretanto, algumas populações de insetos demonstraram resistência a determinados piretróides, indicando a necessidade do desenvolvimento de novos inseticidas eficazes no controle desses vetores. Assim, foi avaliada a atividade inseticida de 83 extratos vegetais, pertencentes a 35 espécies diferentes, em ninfas do primeiro estádio de Dipetalogaster maxima (Uhler, 1894) (Hemiptera: Reduviidae), triatomíneo encontrado no México. Para o teste tópico, foram aplicados 50 ìg de cada extrato nos tergitos abdominais de dez ninfas, em duplicata. Como controles, foram utilizados insetos tratados com etanol, acetona ou sem nenhum tipo de tratamento. Os triatomíneos foram observados durante 28 dias. Nenhum extrato apresentou atividade inseticida significativa, entretanto, o extrato hexânico do fruto e o etanólico da casca do caule de Simarouba versicolor (Simaroubaceae) inibiram a taxa de ecdise em D. maxima (40% e 25%, respectivamente). Sugere-se que estes extratos sejam quimicamente investigados e monitorados por ensaios biológicos a fim de determinar os componentes, para que estes possam ser utilizados como modelos moleculares ou como compostos biorracionais nos programas de controle de insetos.

Nest descriptions of Megalopta aegis (Vachal) and M. guimaraesi Santos & Silveira (Hymenoptera, Halictidae) from the Brazilian Cerrado

We present the first data on the nesting biology of Megalopta aegis and M. guimaraesi from southeastern Brazil. Nests were collected in the Área de Proteção Ambiental Água Limpa, Bauru, São Paulo state. Our data suggest that nest architecture is conserved throughout all species of Megalopta. Two nests of M. guimaraesi consisted of a single female with brood. Of three M. aegis nests, two contained single females with brood and the third nest contained three adult females, with three times more brood than any single female nest. This observation suggests that social behavior in M. aegis is facultative, as known for other Megalopta species.

Bat flies (Diptera, Streblidae and Nycteribiidae) in a Cerrado area of Goiás State, Brazil

A survey of bat flies was carried out in the Brazilian savanna (Cerrado) in the Goiás state, Brazil. We collected 227 specimens of seventeen species belonging to nine genera of Streblidae and seven specimens of four species of Basilia Miranda-Ribeiro, 1903 (Nycteribiidae). Except for Paratrichobius longicrus (Miranda-Ribeiro, 1907) (Streblidae), all species are new recorded in Goiás.

Nutritional ecology of blowflies (Diptera, Calliphoridae): estimates of critical larval weight for pupation on two different

Under natural environmental conditions, blowflies utilize discrete and ephemeral feeding resources such as decaying carcasses. Competition for food on such feeding substrates is usually very severe, and only the individuals that are capable of attaining the critical larval weight for pupation will be able to survive. This critical weight is hitherto unknown for several blowfly species; therefore, the current work is aimed at obtaining such a critical value for four blowfly species of the genera Chrysomya and Lucilia, deploying two types of feeding substrate, namely, artificial diet and macerated bovine meat. On the whole, the critical weights ranged from 30 to 35 mg. The lowest larval weight which permitted pupation was 30.0 mg for Chrysomya megacephala reared on macerated bovine meat. This species was also the best adapted to pupation at low larval weights in relation to the maximum larval weight for males. Regarding the pupation of females, the best-adapted individual was a C. albiceps specimen exhibiting a critical weight that was equal to 39.20 % of the maximum value obtained. Concerning all the species and diet types, the female individuals exhibited the lowest critical weights that produced viable pupae, probably representing an evolutionary strategy that favoured the survival of females, responsible for the egg formation, contributing to the establishment of future generations. Regarding the loss (in percentage) of adult biomass in relation to the third instar larvae, the females of C. megacephala lost less weight than males in both feeding substrates. On the other hand, such a loss of weight occurred in males of C. albiceps and L. cuprina.

Seasonality in insect abundance in the "Cerrado" of Goiás State, Brazil

Seasonality in insect abundance in the "Cerrado" of Goiás State, Brazil. Many studies have provided evidence that tropical insects undergo seasonal changes in abundance and that this is partly due to alternation between the dry and rainy seasons. In the Brazilian "Cerrado" (savannah), this season alternation is particularly evident. The purpose of this work was to study the seasonal abundance of insects in a "Cerrado" area in the municipality of Pirenópolis, Goiás State, Brazil. The insects were captured fortnightly using a light trap between September 2005 and August 2006. The insects collected were separated at the order level and counted. Faunistic analysis was performed to select the predominant insect orders, a multiple linear regression to examine the relation between climatic variables (temperature and precipitation) with the abundance of insects and a circular distribution analysis to evaluate the existence of seasonality in the abundance of insect orders. A total of 34,741 insect specimens were captured, belonging to 19 orders. The orders with the greatest number of specimens were Hymenoptera (8,022), Coleoptera (6,680), Diptera (6,394), Lepidoptera (6,223), Isoptera (2,272), Hemiptera (2,240) and Trichoptera (1,967), which represent 97.3% of all the specimens collected. All the orders, except for Diptera, Isoptera and Trichoptera, showed a relationship with the climate variables (temperature), and all the orders, except for Diptera, presented a grouped distribution, with greater abundance in the transition from the end of the dry season (September) to the start of the rainy one (October/November). A discussion about seasonality on the abundance of the insects is presented.

Behavioral ecology of Heteragrion consors Hagen (Odonata, Megapodagrionidae): a shade-seek Atlantic forest damselfly

Behavioral ecology of Heteragrion consors Hagen (Odonata: Megapodagrionidae): a shade-seek Atlantic forest damselfly. The intensity of the inter and intra-sexual selection can affect male behavioral traits as territorial fidelity and aggressiveness allowing the existence of different strategies. However, its differential success could be affected by environmental - as the diel variation in temperature - and physiological constrains - as the variation in thermoregulatory abilities. In this context, we present a behavioral analysis of Heteragrion consors (Zygoptera, Megapodagrionidae) trying to characterize its mating system, diel activity pattern, temporal budget, territoriality and reproductive biology. These data were obtained based on field observations using the focal individual method and mark-recapture techniques in 120 m of a shaded Atlantic Forest stream in Brazil. The males of this species were territorial, varying in its local fidelity, while the females appear sporadically. Males were perched in the majority of the time, but were also observed in cleaning movements, longitudinal abdominal flexion, wing flexion and sperm transfer during perch. The males presented a perched thermoregulatory behavior related to an exothermic regulation. Foraging and agonistic interactions were rare, but dominate the other behavioral activities. Abdominal movements associated to long lasting copula pointed to the existence of sperm competition in this species. Males performed contact post-copulatory guarding of the females. These observations pointed to a non-resource mating system for this species.

Arthropods associated with pig carrion in two vegetation profiles of Cerrado in the State of Minas Gerais, Brazil

Forensic Entomology research has been concentrated in only a few localities of the "Cerrado" vegetation, the Brazilian Savannah. The present study had, as its objective, an examination of the diversity of arthropod fauna associated with the carcasses of Sus scrofa (Linnaeus) in this biome. The study was conducted during the dry and humid periods in two Cerrado vegetation profiles of the State of Minas Gerais. The decaying process was slower and greater quantities of arthropods were collected during the dry period. Insects represented 99% of 161,116 arthropods collected. The majority of these were Diptera (80.2%) and Coleoptera (8.8%). The entomofauna belong to 85 families and at least 212 species. Diptera were represented by 31 families and at least 132 species. Sarcophagidae (Diptera) and Scarabaeidae (Coleoptera) were the richest groups. Oxysarcodexia (Sarcophagidae) presented the largest number of attracted species, however none of these species bred in the carcasses. The Coleoptera collected belong to at least 50 species of 21 families. Among these species, Dermestes maculatus and Necrobia rufipes were observed breeding in the carcasses. This study showed species with potential importance for estimating the postmortem interval (PMI), indicative of seasonal and environmental type located.

Social wasps of two Cerrado localities in the northeast of Maranhão state, Brazil (Hymenoptera, Vespidae, Polistinae)

Social wasps of two Cerrado localities in the northeast of Maranhão state, Brazil (Hymenoptera, Vespidae, Polistinae). Results are presented of a survey of social wasps from two savanna localities 30 km apart from each other in the northeastern part of the Brazilian state of Maranhão, Brazil: village of Bom Jesus (municipality of Urbano Santos) and village of Tabocas (municipality of Barreirinhas). Two hundred and twenty-seven nests of 31 species of 13 genera were found and mapped. Polybia rejecta was the species with the largest average density of colonies/ha in both areas. The similarity (Jaccard's index) between the Tabocas and Bom Jesus faunas was 41.9%. Twenty-seven species of plants were utilized as nesting substrate. In Tabocas, Qualea parviflora Mart. (Vochysiaceae) trees were used as substrate by 30.3% of the wasp colonies. In Bom Jesus, the vast majority of colonies (27.9%) were found in a secondary vegetation type, the so-called carrasco, indicator of vegetation change. The number of social wasp species recorded in this study is similar to others obtained in several areas of Cerrado vegetation in Brazil. Nine species are new to Maranhão, and Mischocyttarus cerberus had its distribution confirmed, increasing to 58 the number of species known to occur in that state.

Two myrmecophilous scale insects, Cryptostigma urichi (Cockerell) (Hemiptera, Coccidae) and Farinococcus multispinosus Morrison (Hemiptera, Pseudococcidae), cohabiting inside branches of Anadenanthera falcata (Benth.) Speg. (Fabales, Fabaceae) in the Cerrado area of São Paulo State, Brazil

The soft scale Cryptostigma urichi (Cockerell, 1894) and the mealybug Farinococcus multispinosus Morrison, 1922 are reported cohabiting inside branches of Anadenanthera falcata (Benth.) Speg. (Angico-preto), both tended by the ant Azteca oecocordia Longino, 2007 (Hymenoptera, Formicidae). This interaction was observed in the Cerrado region sensu stricto, at the Federal University of São Carlos, UFSCar, Brazil. A. oecocordia is recorded for the first time in Brazil.

Fruit flies (Diptera, Tephritidae) and their parasitoids on cultivated and wild hosts in the Cerrado-Pantanal ecotone in Mato Grosso do Sul, Brazil

Fruit flies (Diptera, Tephritidae) and their parasitoids on cultivated and wild hosts in the Cerrado-Pantanal ecotone in Mato Grosso do Sul, Brazil. Information on frugivorous flies in cultivated or wild host plants and their parasitoids in the Cerrado-Pantanal ecotone in Aquidauana, Mato Grosso do Sul is presented and discussed. Fruit fly samples were collected weekly in specific fruit trees, and McPhail® traps were installed in the same trees for a period of two years. The fruit flies infested ripe and unripe fruits of Averrhoa carambola L., Schoepfia sp., Psidium guajava L. and Pouteria torta (Mart.) Radlk and mature fruits of Anacardium occidentale L. and Inga laurina (Sw.) Willd. Nineteen fruit fly species were obtained with the combination of sampling methods (collecting fruits and trapping), nine of them obtained with both methods, five found only in fruits and five only in traps. This is the first record of Anastrepha striata Schiner in a species of Sapotaceae, as well as for A. castanea Norrbom and A. daciformes Bezzi in Schoepfia sp. (Olacaceae), and for A. distincta Greene in fruits of P. guajava in the state of Mato Grosso do Sul. Fruit collections simultaneously associated with capture of fruit flies by McPhail traps in the same host plants are essential to understand the diversity of fruit flies and their relationship with hosts and parasitoids. Species of Braconidae and Pteromalidae were recovered, where Doryctobracon areolatus (Szépligeti) was the most abundant parasitoid in larvae of tephritids infesting both cultivated and wild host fruits.

Sarchophagid flies (Insecta, Diptera) from pig carcasses in Minas Gerais, Brazil, with nine new records from the Cerrado, a threatened Neotropical biome

Sarchophagid flies (Insecta, Diptera) from pig carcasses in Minas Gerais, Brazil, with nine new records from the Cerrado, a threatened Neotropical biome. The diversity of the Sarcophagidae fauna of the Cerrado biome, also know as the Brazilian Savanna, is still underestimated. In this research we collected flies in the state of Minas Gerais, Brazil, during a Forensic Entomology experiment. Samples were collected throughout the decomposition process of domestic pig (Sus scrofa Linnaeus) carcasses, and the experiments were conducted in areas of pasture and semideciduous forest. A total of 85,694 adult flesh flies belonging to 57 species were collected from all carcasses. New records for nine species of Sarcophaginae are provided, including the first record of Blaesoxipha (Acridiophaga) caridei (Brèthes, 1906) to Brazil, and new occurrences of the following species for the Cerrado and/or for the state of Minas Gerais: Blaesoxipha (Acanthodotheca) acridiophagoides (Lopes & Downs, 1951), Malacophagomyia filamenta (Dodge, 1964), Nephochaetopteryx orbitalis (Curran & Walley, 1934), Nephochaetopteryx cyaneiventris Lopes, 1936, Nephochaetopteryx pallidiventris Townsend, 1934, Oxysarcodexia occulta Lopes, 1946, Ravinia effrenata (Walker, 1861) and Sarcophaga (Neobellieria) polistensis (Hall, 1933).

Diversity and aspects of the ecology of social wasps (Vespidae, Polistinae) in Central Amazonian "terra firme" forest

Diversity and aspects of the ecology of social wasps (Vespidae, Polistinae) in Central Amazonian "terra firme" forest. The knowledge of social wasp richness and biology in the Amazonian region is considered insufficient. Although the Amazonas state is the largest in the region, until now only two brief surveys were conducted there. Considering that the systematic inventory of an area is the first step towards its conservation and wise use, this study presents faunal data on social wasp diversity in a 25 km² area of "terra firme" (upland forest) at the Ducke Reserve, Manaus, Amazonas, Brazil. Wasps were collected in the understory, following a protocol of three collectors walking along 60 trails 1,000 m in extension for 16 days between August and October 2010. Methods used were active search of individuals with entomological nets and nest collecting. Fifty-eight species of social wasps, allocated in 13 genera, were recorded; 67% of the collected species belong to Polybia, Agelaia and Mischocyttarus; other genera were represented by only four species or less. The most frequent species in active searches were Agelaia fulvofasciata (DeGeer, 1773), Agelaia testacea (Fabricius, 1804) and Angiopolybia pallens (Lepeletier, 1836). Twelve species were collected in nests. Prior to this study, 65 Polistinae species were deposited at the INPA Collection. Collecting in the study grid, an area not previously sampled for wasps, resulted in an increase of 25% species, and species richness was 86. According to the results, there is evidence that the diversity of social wasps at the Ducke Reserve is even higher, making it one of the richest areas in the Brazilian Amazonia.

Evidence of phenotypic plasticity of larvae of Simulium subpallidum Lutz in different streams from the Brazilian Cerrado

In this paper, the overall morphological differences between populations of Simulium subpallidumLutz, 1909 are studied. Several studies found in the literature point to a relationship between the labral fans and body size and the habitat where blackfly larvae occur. However, other characteristics potentially related to the microhabitat, such as abdominal hook circlet morphology, which is used for larvae to fix themselves in the substratum, and thoracic prolegs morphology, which help larvae move in the substratum, were analyzed in three different populations of S. subpallidum, one of which occupied a faster flow. The results suggest phenotypic plasticity in S. subpallidum and a tendency toward larger structures in faster flows.

Eficiência relativa de fertilizantes fosfatados no crescimento inicial de eucalipto cultivado em solos do cerrado

Tendo como objetivo avaliar a eficiência relativa do superfosfato simples (SS), fosfato parcialmente acidulado (FAPS) e termofosfato magnesiano (TERM) como fonte de P e outros nutrientes para o cultivo de plantações de eucalipto, em dois solos da região dos Cerrados, uma areia quartzosa (50 g kg-1 de argila) álica e um latossolo vermelho-escuro (230 g kg-1 de argila) álico, foi realizado este experimento, sob condições de casa de vegetação, na ESALQ/USP, Piracicaba (SP), em 1993. Subamostras do AQ receberam 0, 75, 150 e 300 mg kg-1 de P e, do LE, 0, 125, 250 e 500 mg kg-1 de P no solo. As doses de P foram estimadas com base na solubilidade dos adubos; SS e FAPS, em citrato de amônio, e TERM, em ácido cítrico 20 g L-1. Em cada vaso (5 kg de solo), deixou-se uma planta de Eucalyptus grandis por 90 dias após a emergência e desbaste das plântulas. Paralelamente ao experimento em casa de vegetação, subamostras de todos os tratamentos, com 2 kg de solo, foram incubadas no interior de sacos plásticos por 0, 10, 20, 40, 60 e 80 dias. Ao término de cada período de incubação, os solos eram amostrados e analisados. Mediante o cálculo de índices de eficiência relativa entre os adubos, verificou-se que o TERM foi superior 64% ao SS e 57% ao FAPS no solo AQ. No LE, o SS foi superior 55% ao TERM e 34% ao FAPS. O TERM foi a fonte de P que promoveu os maiores acréscimos do nível de fertilidade dos solos, com expressiva elevação do pH do solo, redução das concentrações de Al e aumento daquelas de Ca e Mg. Os ganhos de produção das mudas de eucalipto foram altamente correlacionados com a absorção de P, K, Ca, Mg e Zn. O TERM proporcionou as maiores absorções desses nutrientes no solo AQ e, as menores, de P, Ca e Zn no LE. As distintas respostas de crescimento para os adubos avaliados, em ambos os solos, sobretudo para TERM e SS, foram atribuídas, em grande parte, aos efeitos secundários das fontes de P sobre a fertilidade dos solos.