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1.
Zootaxa ; 4958(1): zootaxa.4958.1.10, 2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33903457

RESUMEN

Microvelia joceliae Magalhães Moreira, sp. nov. is described and illustrated based on material from Parque Natural Municipal das Andorinhas, Minas Gerais State, in southeastern Brazil. The new species can be distinguished from congeners occurring in the region by the pronotum of the apterous form covering almost the entire thorax dorsally, proepisternum with black denticles, male abdominal segments V-VII ventrally depressed, shape of the asymmetrical parameres, and female abdominal laterotergites reflected over the mediotergites and almost touching over segments V-VII.


Asunto(s)
Heterópteros , Animales , Brasil , Femenino , Heterópteros/anatomía & histología , Heterópteros/clasificación , Masculino , Pigmentación , Especificidad de la Especie
2.
Environ Monit Assess ; 193(1): 12, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33325004

RESUMEN

Silviculture can be considered a sustainable alternative to the extraction of wood from natural forests in Brazil. However, the high demand for wood products has decreased the area of natural Cerrado due to land transformation for forestry activities. This transformation could lead to the loss of species, including insects that cannot tolerate the new environment dominated by exotic plant species. This study aims to evaluate whether the presence of an extensive Eucalyptus silviculture in the Brazilian Cerrado decreases the integrity of nearby riparian environments and, consequently, decreases odonate diversity. Thirteen ponds were selected in patches of Cerrado embedded within a matrix of Eucalyptus silviculture in order to assess habitat integrity of ponds and their riparian zones and collect adult odonates. The physical integrity of the study sites was measured using a Habitat Integrity Index (HII) designed to determine the degree of conservation of aquatic environments. The HII of the study sites varied between 0.44 and 0.80, indicating differences in the degree of conservation. Therefore, a positive relationship was found between odonate richness and abundance and HII, and between the abundance of zygopterans and anisopterans and HII. These findings may be due to the fact that these insects are adapted to the natural resources maintained at the most conserved habitats, and which were lost in degraded riparian zones, such as the presence of aquatic vegetation and a diversity of organic debris on pond banks. We conclude that the conversion of natural areas to Eucalyptus silviculture can alter the integrity of nearby riparian zones and, consequently, odonate diversity.Graphical abstract.


Asunto(s)
Eucalyptus , Odonata , Animales , Biodiversidad , Brasil , Conservación de los Recursos Naturales , Ecosistema , Monitoreo del Ambiente
3.
J Ethnopharmacol ; 260: 112898, 2020 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-32437835

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Equisetum giganteum has been traditionally used as an anti-diabetic herbal remedy to treat diabetes in the southern state of Rio Grande do Sul in Brazil. AIM OF THE STUDY: Considering the ethonopharmacology and historical importance of E. giganteum, its potential antidiabetic effect was evaluated in alloxan induced diabetic rabbits. MATERIAL AND METHODS: Samples of Equisetum giganteum were collected in the city of Ouro Preto, Minas Gerais, Brazil. Butanolic and aqueous extracts were prepared and subsequently evaluated for anti-diabetic properties in vivo using albino male rabbits. At the end of the treatment period, the animals were euthanized, and histopathological analysis were carried out. The following biochemical parameters were studied: glucose, triacylglycerol, cholesterol, albumin, creatinine, glycosylated hemoglobin and lipase. The phytochemical profile of the extracts was studied by liquid chromatography techniques coupled to a UV/VIS detector and high-resolution mass spectrometry. RESULTS: Both aqueous and butanolic extracts were capable of reducing significantly the levels of glucose, cholesterol and triacylglycerol and thus demonstrating their hypolipidemic and hypoglycemiant effects. Furthermore, the extracts prevented the occurrence of hepatic complications during treatment. The phytochemical profile of the extracts was investigated, and the natural products detected were in agreement with those that had been previously described in the literature. CONCLUSION: Based on the significant reductions in biochemical parameters and the histologic evidence for the absence of complications in the liver, pancreas of the treated animals, Equisetum giganteum can be a therapeutically relevant resource in the treatment of diabetes and hyperlipidemia.


Asunto(s)
Glucemia/efectos de los fármacos , Diabetes Mellitus Experimental/tratamiento farmacológico , Equisetum , Hipoglucemiantes/farmacología , Extractos Vegetales/farmacología , Aloxano , Animales , Biomarcadores/sangre , Glucemia/metabolismo , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/inducido químicamente , Diabetes Mellitus Experimental/patología , Equisetum/química , Hemoglobina Glucada/metabolismo , Hipoglucemiantes/aislamiento & purificación , Lípidos/sangre , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Páncreas/efectos de los fármacos , Páncreas/metabolismo , Páncreas/patología , Extractos Vegetales/aislamiento & purificación , Conejos
4.
Biota Neotrop. (Online, Ed. ingl.) ; 19(1): e20180609, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-974024

RESUMEN

Abstract: Odonata is considered, among the aquatic insect orders, the second largest group in number of species. Its global richness is estimated in about 6,000 described species. The Brazilian richness represents around 14% of the world's odonatofauna, however, the knowledge on Brazilian dragonflies distribution is still poor. This study purpose an inventory of the dragonflies species present in aquatic habitats from a Preserved Area according to the Brazilian Forest Code, located in the Cerrado biome at Triângulo Mineiro, Minas Gerais. In the dry season, from April to June of 2017, we collected 680 specimens belonging to 36 species and six families. Among the collected species, Elasmothemis williamsoni was observed by the first time in Minas Gerais State, and we also found a new species of Tigriagrion (Zygoptera: Coenagrionidae) which is being described by taxonomists. Considering the fast agricultural advance over natural Cerrado systems, species lists can be important to define priority conservation areas for odonate species.


Resumo: Odonata é considerada a segunda ordem de insetos com maior número de espécies de insetos aquáticos. Sua riqueza global é estimada em cerca de 6.000 espécies descritas. A odonatofauna encontrada no Brasil representa cerca de 14% da riqueza mundial, no entanto, o conhecimento sobre a distribuição de libélulas brasileiras ainda é incipiente. Este estudo teve como objetivo um inventário das espécies de libélulas presentes em habitats aquáticos de uma Área Preservada de acordo com o Código Florestal Brasileiro, localizada no bioma Cerrado do Triângulo Mineiro, em Minas Gerais. Na estação seca, de abril a junho de 2017, foram coletados 680 espécimes pertencentes a 36 espécies e seis famílias. Entre as espécies coletadas, Elasmothemis williamsoni foi observada pela primeira vez no Estado de Minas Gerais, e foi encontrada também uma nova espécie de gênero Tigriagrion (Zygoptera: Coenagrionidae) que está sendo descrita. Considerando o rápido avanço da agricultura sobre os sistemas naturais do Cerrado, as listas de espécies podem ser importantes para definir áreas prioritárias para a conservação de espécies de Odonata.

5.
Environ Entomol ; 47(6): 1413-1419, 2018 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-30395190

RESUMEN

The longhorn beetles play important roles in the forest ecosystem processes and their diversity is affected by many environmental disturbances worldwide. This study aimed at understanding how the structural heterogeneity of the habitat can affect the longhorn beetle assemblage in three areas of an Atlantic Forest, which suffered differential impacts in the past and are now in different successional stages. The area in the most advanced successional stage had mainly lower density of trees, but with greater availability of dead wood, especially larger diameter classes. They are important forest components that contribute to the structural diversity of the habitat providing resources for a variety of dependent species. This area has also shown the greatest richness and abundance of longhorn beetles. Our results suggest that these beetles are closely associated with the structural heterogeneity of forests and can be valuable indicators for assessing biodiversity and quality of forest habitat. It also shows that old-growth forest remnants can be the key to the maintenance of the diversity of the longhorn beetles and, consequently, of the ecosystem services they provide.


Asunto(s)
Escarabajos , Bosques , Animales , Brasil
6.
PLoS One ; 13(5): e0195565, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29775458

RESUMEN

This study describes differences in species richness and composition of the assemblages of galling insects and their host plants at different spatial scales. Sampling was conducted along altitudinal gradients composed of campos rupestres and campos de altitude of two mountain complexes in southeastern Brazil: Espinhaço Range and Mantiqueira Range. The following hypotheses were tested: i) local and regional richness of host plants and galling insects are positively correlated; ii) beta diversity is the most important component of regional diversity of host plants and galling insects; and iii) Turnover is the main mechanism driving beta diversity of both host plants and galling insects. Local richness of galling insects and host plants increased with increasing regional richness of species, suggesting a pattern of unsaturated communities. The additive partition of regional richness (γ) into local and beta components shows that local richnesses (α) of species of galling insects and host plants are low relative to regional richness; the beta (ß) component incorporates most of the regional richness. The multi-scale analysis of additive partitioning showed similar patterns for galling insects and host plants with the local component (α) incorporated a small part of regional richness. Beta diversity of galling insects and host plants were mainly the result of turnover, with little contribution from nesting. Although the species composition of galling insects and host plant species varied among sample sites, mountains and even mountain ranges, local richness remained relatively low. In this way, the addition of local habitats with different landscapes substantially affects regional richness. Each mountain contributes fundamentally to the composition of regional diversity of galling insects and host plants, and so the design of future conservation strategies should incorporate multiple scales.


Asunto(s)
Altitud , Biodiversidad , Pradera , Insectos/clasificación , Insectos/fisiología , Plantas/parasitología , Animales , Brasil , Ecosistema , Interacciones Huésped-Parásitos
7.
Environ Entomol ; 46(6): 1243-1253, 2017 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-29087532

RESUMEN

In this work, we investigated the factors that determine the distribution of galling insects in high-altitude grasslands, locally called 'campos de altitude' of Mantiqueira Range and tested whether 1) richness of galling insects decreases with altitude, 2) galling insect richness increases with plant richness, 3) variation in galling insect diversity is predominantly a consequence of its ß component, and 4) turnover is the main mechanism driving the beta diversity of both galling insects and plants. Galling insect richness did not exhibit a negative relationship with altitude, but it did increase with plant richness. The additive partition of regional richness (γ) into its local and beta components showed that local diversity (α) of galling insects and plants was relatively low in relation to regional diversity; the ß component incorporated most of the regional diversity. This pattern was also found in the multiscale analysis of the additive partition for galling insects and plants. The beta diversity of galling insects and plants was driven predominantly by the process of turnover and minimally by nesting. The results reported here point out that the spatial distribution of galling insects is best explained by historical factors, such as the distribution of genera and species of key host plants, as well as their relation to habitat, than ecological effects such as hygrothermal stress - here represented by altitude.


Asunto(s)
Biodiversidad , Pradera , Insectos , Plantas , Altitud , Animales , Brasil , Insectos/clasificación , Tumores de Planta , Plantas/clasificación
8.
Acta amaz ; 47(3): 237-246, July-Sept. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-885967

RESUMEN

ABSTRACT Topographic gradients in terra firme forests are associated with pronounced changes in soil texture, soil nutrients and distance to the water-table, thereby creating different hydric and nutritional conditions for plants and their associated herbivore community. The aim of this study was to investigate galling species and host plant richness and gall species composition across topographic habitats differing in nutrient and water stress in the Brazilian Amazon rainforest. Nineteen 250 x 3 m plots were randomly sampled in the valley, slope, plateau-slope transition, and plateau habitats in terra firme forests. All individual dicotyledonous plants 1 to 3 meters high were examined for the presence of insect galls. Galling species and host plant richness differed significantly among the studied habitats and were higher in slope habitats (drier habitats), as expected. More humid areas (valleys) showed the lowest richness of galling species, and a lower number of understory host plants. PERMANOVA and PERMDISP results demonstrated that the gall species composition differed significantly in the valley, slope, plateau-slope transition, and plateau areas. However, these structural differences in species composition could be due to unequal dispersion of variability among forest habitats. Our data suggested that spatial heterogeneity, such as a mosaic of local water status and nutrient availability resulting from the topographic conditions, can affect host plants and their associated galling insects.


RESUMO As variações topográficas encontradas nas florestas de terra firme são acompanhadas por fortes mudanças no conteúdo de argila e concentração de nutrientes do solo, criando, portanto, diferentes condições hídricas e nutricionais para plantas e as comunidades de herbívoros associadas. O objetivo do presente estudo foi avaliar a riqueza e composição de espécies de insetos galhadores e suas plantas hospedeiras ao longo de um gradiente topográfico com habitats que diferem quanto ao estresse hídrico e nutricional. Dezenove parcelas de 250 x 3 m foram estabelecidos aleatoriamente em habitats de vertente, platô, transição platô-vertente e baixio, claramente distintos em áreas de terra firme. Todas as dicotiledôneas com 1 a 3 metros de altura foram examinadas quanto à presença de galhas de insetos. As galhas encontradas foram coletadas e insetos galhadores foram classificados em morfoespécies. A riqueza de galhadores e de plantas hospedeiras diferiram significativamente entre os habitats estudados, e como esperado, foi maior no habitat de vertente. As áreas mais úmidas (baixios) apresentaram menor riqueza de plantas hospedeiras no sub-bosque e, conseqüentemente, um número menor de espécies de galhadores. Os resultados das análises de PERMANOVA e PERMDISP demonstraram que a composição da espécie de insetos galhadores variou significativamente entre as áreas de floresta de terra firme. No entanto, essas diferenças estruturais na composição das espécies podem ser devidas à dispersão desigual da variabilidade entre os habitats. Nossos dados sugerem que a heterogeneidade espacial, tal como o mosaico de status hídrico e nutricional do solo associado às condições topográficas, pode afetar plantas hospedeiras e insetos galhadores associados.


Asunto(s)
Variación Genética , Ecosistema , Bosque Lluvioso
9.
Biota neotrop. (Online, Ed. port.) ; 13(4): 139-151, Oct-Dec/2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-703575

RESUMEN

Gall-inducing insects are very specious in vegetations of southeastern Brazil. Our goal was describe the gall richness by characterizing their external forms and their patterns of occurrence on host plants. Samples were collected from Campos de Altitude at four regions of the Mantiqueira Range: 1) Parque Estadual da Serra do Brigadeiro, 2) Parque Nacional do Caparaó, 3) Parque Estadual do Ibitipoca, 4) Parque Nacional do Itatiaia. We found 93 gall species within 13 families, 30 genera and 50 host plant species. We recorded 38 gall species in Parque Estadual da Serra do Brigadeiro, 21 in Parque Nacional do Caparaó, 23 in Parque Estadual do Ibitipoca and 20 in Parque Nacional do Itatiaia. Asteraceae represented 33% of the species collected, followed by Melastomataceae at 17%; with each one concentrating 56% and 18% of the galling insects, respectively. 98% of galls were Cecydomiidae (Diptera). The most attacked organ was the stem (56%), followed by the leaf (23%). Only 12% of the galls described in our study had been already recorded in previous studies, thus reinforcing the need to increase the sampling effort toward a better understanding of the richness and the natural history of gall-inducing insects from Brazil.


Insetos indutores de galhas são muito ricos em espécies nas formações vegetais do sudeste do Brasil. O objetivo deste estudo foi descrever a riqueza de morfotipos de galha por meio da caracterização de suas formas externas e os padrões de ocorrência nas plantas hospedeiras. As amostragens foram realizadas em campos rupestres e altitudinais de quatro regiões da Serra da Mantiqueira: 1) campos de altitude do Parque Estadual do Brigadeiro e 2) Parque Nacional do Caparaó, 3) Parque Estadual do Ibitipoca e Parque Nacional do Itatiaia. Foram registradas 93 espécies de galhas induzidas por insetos em 13 famílias, 30 gêneros e 50 espécies de plantas hospedeiras. Sendo 38 a riqueza de insetos indutores de galhas do Parque Estadual do Brigadeiro, 21 do Parque Nacional do Caparaó, 23 do Parque Nacional do Caparaó e 20 do Parque Nacional do Itatiaia. As famílias com maior riqueza foram Asteraceae (33%) e Melastomataceae (17%). A família Cecydomiidae (Diptera) foi a mais frequente (98%). O órgão mais atacado foi o caule (56%) seguido de folha (23%). O fato de apenas 12% das galhas descritas neste estudo já terem sido registradas em trabalhos anteriores, reforça a necessidade em aumentar o esforço amostral na direção de um maior conhecimento sobre a riqueza e história natural dos insetos indutores de galhas no Brasil.

10.
Biota neotrop. (Online, Ed. port.) ; 13(3): 102-109, 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-693999

RESUMEN

Our goal was describe the gall richness through the characterization of their external shapes and occurrence patterns in their host plants from Parque Estadual da Serra do Cabral. In a universe of 34 families, 64 genera and 89 plant species, 47 gall-inducing insects in 21 families, 32 genera and 39 host plant species were recorded. The families, which hosted higher gall richness, were those with highest abundance. Asteraceae represented 33% of the species collected followed by Malpighiaceae 8% and Fabaceae 8%, each one concentrating 25%, 19% and 8% of gall-inducing insects, respectively. The organ most attacked was the leaf (51%), followed by the stem (42%) and the terminal branch (4%). Ninety-six percent (96%) of galls were glabrous. Only 25.5% of the galls described in our study have been already recorded in previous studies, reinforcing the need to increase the sampling effort toward a better understanding of the richness, distribution, and natural history of gall-inducing insects from Brazil.


Objetivo deste estudo foi descrever a riqueza de morfotipos de galha por meio da caracterização de suas formas e os padrões de ocorrência em suas plantas hospedeiras no Parque Estadual da Serra do Cabral. Num universo de 34 famílias, 64 gêneros e 89 espécies de plantas, foram registradas 47 espécies de galhas induzidas por insetos em 21 famílias, 32 gêneros e 39 espécies de plantas hospedeiras. As famílias que concentraram maior riqueza de insetos galhadores foram as famílias mais abundantes. A família Asteraceae representou 33% das espécies coletadas, seguida das Malpighiaceae 8% e Fabaceae 8%, cada uma concentrando 25%, 19% e 8% das espécies de insetos galhadores, respectivamente. O órgão mais atacado foi a folha (51%), seguido do caule (42%) e ramo terminal (4%). Noventa e seis por cento (96%) das galhas foram glabras. O fato de apenas 25% das galhas descritas neste estudo já terem sido registradas em trabalhos prévios, reforça a necessidade em aumentar o esforço amostral na direção de um maior conhecimento sobre a riqueza, distribuição e história natural dos insetos indutores de galhas no Brasil.

11.
Rev. bras. entomol ; 52(1): 78-81, 2008. graf
Artículo en Inglés | LILACS | ID: lil-481216

RESUMEN

The plant architecture hypothesis predicts that variation in host plant architecture influences insect herbivore community structure, dynamics and performance. In this study we evaluated the effects of Macairea radula (Melastomataceae) architecture on the abundance of galls induced by a moth (Lepidoptera: Gelechiidae). Plant architecture and gall abundance were directly recorded on 58 arbitrarily chosen M. radula host plants in the rainy season of 2006 in an area of Cerrado vegetation, southeastern Brazil. Plant height, dry biomass, number of branches, number of shoots and leaf abundance were used as predicting variables of gall abundance and larval survival. Gall abundance correlated positively with host plant biomass and branch number. Otherwise, no correlation (p > 0.05) was found between gall abundance with shoot number or with the number of leaves/plant. From a total of 124 galls analyzed, 67.7 percent survived, 14.5 percent were attacked by parasitoids, while 17.7 percent died due to unknown causes. Larvae that survived or were parasitized were not influenced by architectural complexity of the host plant. Our results partially corroborate the plant architecture hypothesis, but since parasitism was not related to plant architecture it is argued that bottom-up effects may be more important than top-down effects in controlling the population dynamics of the galling lepidopteran. Because galling insects often decrease plant fitness, the potential of galling insects in selecting for less architectural complex plants is discussed.


A hipótese da arquitetura de planta prediz que variações na arquitetura da planta hospedeira influenciam a comunidade de insetos herbívoros, sua dinâmica e performance. Neste estudo o efeito da arquitetura de Macairea radula (Melastomataceae) na abundância de galhas induzidas por uma mariposa (Lepidoptera: Gelechiidae) foi avaliado. A arquitetura da planta e a abundância de galhas foram diretamente registradas em 58 indivíduos de M. radula arbitrariamente selecionados durante a estação chuvosa de 2006 em uma área de Cerrado no sudeste brasileiro. A altura da planta, biomassa seca, número de ramos e abundância de galhas foram utilizados como variáveis para prever a abundância de galhas e sobrevivência das larvas. A abundância das galhas foi positivamente correlacionada com a biomasssa seca e o número de ramos secundários. Por outro lado, nenhuma correlação (p > 0.05) foi encontrada entre a abundância de galhas e ramos terciários e número de folhas por planta. De um total de 124 galhas analisadas, 67,7 por cento sobreviveram, 14,5 por cento foram parasitadas e 17,7 por cento morreram por causas indeterminadas. No entanto, o parasitismo e sobrevivência das larvas não foram influenciados pela complexidade arquitetônica da planta hospedeira. Os resultados corroboram parcialmente a hipótese de arquitetura da planta, mas como o parasitismo não foi relacionado com a arquitetura da planta, os efeitos reguladores de níveis inferiores da cadeia alimentar possivelmente são mais importantes do que os efeitos de níveis superiores da cadeia alimentar na dinâmica populacional do galhador.


Asunto(s)
Animales , Pradera , Lepidópteros/fisiología , Melastomataceae , Tumores de Planta/parasitología , Brasil , Interacciones Huésped-Parásitos
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