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Population dynamic studies help understand how biotic and abiotic factors can affect pest populations and their natural enemies. The red palm mite, Raoiella indica Hirst (Acari: Tenuipalpidae), is an invasive species that severely damages coconut and banana trees and threatens several Arecaceae species in the Americas. In the present study, populations of R. indica were monthly monitored for 16 months in a coconut plantation in Boa Vista, Roraima, Brazil, to evaluate the contribution of natural enemies and climatic factors on population dynamics of this pest. Linear models were adjusted to determine how average air temperature, relative humidity, rainfall, and predators affect the abundance of R. indica over time. Rainfall and high air temperatures were the main factors reducing R. indica populations. During the drier months of the year, from September to March (average temperatures approximately 27.6 °C), the densities of R. indica were highest, and severe damage, such as yellowing and leaf necrosis, was observed on the plants. The most abundant predator was Amblyseius largoensis (Muma) (Acari: Phytoseiidae). Its density was positively influenced by R. indica and negatively affected by rainfall and high temperatures. Furthermore, the population of A. largoensis was reduced in drier periods and grew slower than R. indica after this period; thus, studies evaluating the release of this predator at the beginning of the rainy season are necessary to assess its effectiveness in regulating R. indica. This is the first report of insect predatory insects, namely Stethorus sp. (Coleoptera: Coccinellidae) and Thysanoptera: Phlaeothripidae, regulating R. indica in Brazil. [ABSTRACT FROM AUTHOR]

In this long-term study we evaluated the diversity and seasonality of predatory insects (Diptera: Syrphidae and Asilidae) in Brachiaria decumbens monoculture and silvopastoral systems in Southeast Brazil. The study was conducted in Coronel Pacheco municipality, Minas Gerais state, Brazil, between February 2010 and January 2015. Insects were collected with malaise traps installed in both monoculture and silvopastoral systems. Specimen abundance, family diversity, seasonality assessed by circular analysis, the degrees of association between specimen number and climatic variables measured by Spearman's correlation, and the constancy and similarities of Syrphidae and Asilidae were analyzed in the monoculture and silvopastoral systems. Eleven species of hoverflies (Diptera: Syrphidae) were collected, five and three of which were exclusive to the silvopasture and monoculture, respectively. The number of specimens within the monoculture was significantly greater than that in the silvopasture. Twenty-four species of robber flies (Diptera: Asilidae) were collected, two of which were exclusive to the monoculture and eight to the silvopasture. The abundance of robber flies in the silvopasture was not significantly different from that in the monoculture. Syrphidae diversity was greater in the monoculture and was not significantly different from robber fly family diversity. Circular analysis revealed seasonality, with the distribution grouped during dry periods for hoverflies and dispersed for robber flies. Most hoverflies and robber flies were accidental in each of the systems. Further studies on the capacity of these predator species to act as biological control agents of pasture pests are required. This study presents important and promising results for understanding the dynamics of the Syrphidae and Asilidae community in monoculture and silvopastoral systems in Brazil. [ABSTRACT FROM AUTHOR]

The new ichnospecies Paleohelcura araraquarensis isp. nov. is described from the Upper Jurassic-Lower Cretaceous Botucatu Formation of Brazil. This formation records a gigantic eolian sand sea (erg), formed under an arid climate in the south-central part of Gondwana. This trackway is composed of two track rows, whose internal width is less than one-quarter of the external width, with alternating to staggered series, consisting of three elliptical tracks that can vary from slightly elongated to tapered or circular. The trackways were found in yellowish/reddish sandstone in a quarry in the Araraquara municipality, São Paulo State. Comparisons with neoichnological studies and morphological inferences indicate that the producer of Paleohelcura araraquarensis isp. nov. was most likely a pterygote insect, and so could have fulfilled one of the ecological roles that different species of this group are capable of performing in dune deserts. The producer could have had a herbivorous or carnivorous diet or been part of the fauna of omnivores, being able to adopt herbivorous, carnivorous, and saprophagous diets when necessary. In modern dune deserts, some species of pterygote insects are detritivores (like Tenebrionidae), relying on organic matter that accumulated among the sand grains of the dunes during dry periods with no plant growth. The presence of additional burrows suggests that the Botucatu paleodesert would have had a detritivorous fauna like this. Based on the interpretation of the ichnofossil producers, it was possible to reconstruct the food web of this paleodesert. All the omnivorous and herbivorous invertebrates and the herbivorous ornithopod dinosaurs made up the primary consumers. These animals were, in turn, the food source for bigger carnivorous or omnivorous animals unable to feed on detritus, like arachnids, possible predatory insects, mammaliaforms, and theropod dinosaurs. The highest trophic level was occupied by larger theropod dinosaurs and mammaliaforms, which, because of their size, could prey upon a wide range of animals. The producer of Paleohelcura araraquarensis isp. nov. could have been a primary consumer if it were an omnivorous detritivore or a herbivore, or a secondary consumer if it were produced by a predatory insect or an omnivore relying on animal biomass. The description of this new trackway expands the knowledge on the faunal composition of the Botucatu paleodesert and provides insights into the ecological relationships in ancient deserts. The presence of these arthropod trackways in Mesozoic eolian deposits helps to trace a continuity between Paleozoic and post-Paleozoic desert ichnofaunas, further reinforcing a single Octopodichnus—Entradichnus Ichnofacies for eolian deposits. [ABSTRACT FROM AUTHOR]

Natural enemy conservation is known to be affected by ecological processes that range from local to landscape scales. At the farm scale, there are cropped and noncropped areas that differ in their management and plant diversity; these differences affect the spatiotemporal dynamics of natural enemies.We investigated how different habitat types can affect the conservation and spatial dynamics of predatory and herbivore insects in organic vegetable crops in Brazil. Insects were simultaneously sampled in two cropped (focal and neighbourhood crops) and two noncropped habitats (fallow and native forests) during five consecutive focal crop cycles.We found a higher species richness of predators and herbivores in noncropped habitats. All of the habitats shared species from both functional groups throughout the year, indicating that species could disperse among habitats. Fallow areas can serve as a source and sink for species migrating to/from cropped habitats where predators and herbivores can numerically increase their populations during the crop cycles.The spatiotemporal dynamics of herbivores and predators depend on the management and maintenance of natural, seminatural and cropped habitats within the farm. [ABSTRACT FROM AUTHOR]

Biotype B of the whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), causes considerable losses to growers worldwide. Phytoseiid mites have been successfully used for the control of this pest in several countries. The Brazilian phytoseiid fauna is very diverse and potentially useful for this purpose. The aim of this study was to evaluate five Brazilian populations of phytoseiids as candidates for the control of the whitefly, a serious pest of different crops worldwide. Evaluated species were Amblydromalus limonicus (Garman & McGregor), Amblyseius herbicolus (Chant), Amblyseius largoensis (Muma), Amblyseius tamatavensis (Blommers), and Neoseiulus tunus (De Leon), which are found naturally in Brazil and elsewhere. The work was conducted at 28 ± 1°C, 75 ± 10% relative humidity, and a photoperiod of 12:12 (L:D) h. All evaluated phytoseiids preyed on eggs of B. tabaci, with the highest levels of predation recorded for Am. herbicolus and N. tunus, and highest level of oviposition recorded for Am. tamatavensis. The results show the Brazilian populations of those three species to be promising as control agents of B. tabaci. Aleuroglyphus ovatus (Troupeau) (Acari: Acaridae) was found to be a suitable prey for the mass production of those predators. Complementary studies are considered justified, given the positive results of this study. [ABSTRACT FROM PUBLISHER]

Highlights: [•] The thrips Gynaikothrips ficorum and its predator Montandoniola confusa are associated and spreading alongside one another throughout Brazil. [•] M. confusa prey upon all thrips life stages and exhibits a type II functional response. [•] It is estimated ∼10-fold greater predation on eggs compared to larvae/prepupae and adult thrips. [Copyright &y& Elsevier]

The tomato borer Tuta absoluta, native to western South America, is an extremely devastating pest in tomato crops in most of South America, Europe and Africa North of the Sahel, causes yield losses up to 100% and decreases fruit quality in open field and greenhouse crops if control methods are not applied. In Brazil two other important lepidopteran pests - Neoleucinodes elegantalis and Helicoverpa zea - occur in tomato, as well as thrips, whiteflies and aphids. For control of these pests, frequent applications of pesticides of up to 5 times per week are needed, and these resulted in the appearance of resistant populations to a number of active ingredients and decimation of natural enemies. Biological control may offer a better, safer and more sustainable opportunity for pest management. Mirid predatory bugs are currently used with success in southern Europe to control T. absoluta and other pests. In Brazil, four Hemipteran predatory bugs, not yet known to attack T. absoluta, were found to successfully prey on eggs and larvae of this pest. The first results on their predation capacity, development, survival and reproduction on T. absoluta on tomato plants are presented. [ABSTRACT FROM AUTHOR]

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The tomato red spider mite, Tetranychus evansi, is reported as a severe pest of tomato and other solanaceous crops from Africa, from Atlantic and Mediterranean Islands, and more recently from the south of Europe (Portugal, Spain and France). A population of the predaceous mite Phytoseiulus longipes has been recently found in Brazil in association with T. evansi. The objective of this paper was to assess the development and reproduction abilities of this strain on T. evansi under laboratory conditions at four temperatures: 15, 20, 25 and 30°C. The duration of the immature phase ranged from 3.1 to 15.4 days, at 30 and 15°C, respectively. Global immature lower thermal threshold was 12.0°C. Immature survival was high at all temperatures tested (minimum of 88% at 30°C). The intrinsic rate of increase (rm) of P. longipes ranged from 0.091 to 0.416 female/female/day, at 15 and 30°C, respectively. P. longipes would be able to develop at a wide range of temperatures feeding on T. evansi and has the potential to control T. evansi populations. [ABSTRACT FROM AUTHOR]

The article focuses on a study on the occurrence of predatory Coccinellidae species in low-input crops in Pernambuco, Brazil. The study was part of a survey on the predatory entomofauna survey in agro-ecosystems in the country's semi-arid region. It aimed to explore bionomics and distribution of described Coccinellidae species and to identify species which can be potential agents for natural biological controls of two local pests.