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1.
Zootaxa ; 3641: 1-20, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26287062

RESUMEN

Three new Neotropical species of Hygronemobius Hebard are described from Atlantic Forest remnants in southeastern Brazil: Hygronemnobius indaia sp. n. and Hygroneinobius iperoigae sp. n. from the state of São Paulo and Hygroneinobius guriri sp. n. from the state of Espírito Santo. We provide photographs of types and male genitalia, and discuss the morphology of male genitalia, taxonomy, calling songs and biogeographic distribution of the genus.


Asunto(s)
Ortópteros/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Brasil , Femenino , Genitales Masculinos/anatomía & histología , Genitales Masculinos/crecimiento & desarrollo , Masculino , Tamaño de los Órganos , Ortópteros/anatomía & histología , Ortópteros/crecimiento & desarrollo
2.
Ambio ; 49(12): 2061-2067, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32621009

RESUMEN

National parks are under attack in many parts of the world, including Brazil, which the Convention on Biodiversity ranks as the world's most biodiverse country. Brazil has been experiencing an unprecedented environmental crisis, and the political situation in the country favors approval of environmentally damaging measures by both the legislative and executive branches of government. A new and largely unreported setback is a proposal in the National Congress for a road cutting the Iguaçu National Park in two. Here, we identify environmental threats from the proposed road and pressures on the park from the surrounding human population. The proposed laws violate Brazil's constitution and would cause immeasurable damage to the park's biodiversity and associated ecosystem services. The road would reduce the cost of transport between two municipalities (counties), but not the cost of transporting soybeans, their main agricultural product. However, the local population would be better served by strengthening its ties to the park and promoting economic alternatives such as tourism, agroforestry, and organic agriculture. The Caminho do Colono road illustrates the danger posed by downgrading the status of protected areas in order to allow environmentally damaging activities. This trend is occurring in many countries and is especially evident in Brazil.


Asunto(s)
Ecosistema , Parques Recreativos , Biodiversidad , Brasil , Conservación de los Recursos Naturales , Humanos
3.
Integr Environ Assess Manag ; 16(5): 622-630, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32470204

RESUMEN

On November 2015, Samarco tailings dam in Mariana, Minas Gerais, Brazil, collapsed, releasing 62 million tons of tailings that advanced through 668 km of the Doce River and adjacent floodplain. Although the collapse was the worst environmental disaster in Brazil, little is known about its consequences to aquatic biota. Here we evaluate the effects of the tailings mudflow on metal and As concentration in fish and how concentration correlates with water and fish characteristics. We quantified semitotal amounts of Ag, Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn in fish muscle tissue using inductively coupled plasma mass spectrometry (ICP-MS) in 255 individuals (34 species) sampled in unaffected and affected areas along the Doce River basin. Arsenic and Hg were higher in fish from affected sites, likely due to turbulent mixing of previously sedimented material by the giant tailings wave. Silver and Zn concentrations were higher in unaffected sites. Arsenic concentration in Geophagus brasiliensis decreased with increasing fish weight. Copper and Zn decreased with increasing fish weight considering the whole assembly of fish. The tailings mudflow increased water conductivity, and conductivity increased Al concentration in fish, so we expected a larger Al concentration in fishes from affected sites. However, the observed Al concentration in fishes from affected sites was lower than expected by water conductivity. Thus, the tailings mudflow reduced Al uptake or accumulation in fishes. Mercury decreased with increasing water conductivity in both unaffected and affected sites considering all species and in G. brasiliensis alone. Despite the relatively low concentration range of metals and As found in fish, fishes from sites affected by the Fe ore tailings mudflow showed higher As and Hg concentration, compared to fishes from unaffected sites. The higher As and Hg in affected sites require further detailed monitoring to ensure safeguards of human health by fishing activity along the Doce River. Integr Environ Assess Manag 2020;16:622-630. © 2020 SETAC.


Em novembro de 2015, a barragem de rejeitos da Samarco em Mariana, MG, Brasil, rompeu, liberando 62 milhões de toneladas de rejeitos de minério de ferro que avançaram por 668 km do rio Doce e planície adjacente. Embora este tenha sido considerado o pior desastre ambiental do país, pouco se sabe sobre as consequências da liberação do fluxo de lama para a biota aquática. Aqui avaliamos os efeitos do fluxo de lama de rejeitos sobre a bioacumulação de metais e arsênio em várias espécies de peixes coletadas na bacia do rio Doce e como a bioacumulação se correlaciona com as características da água e dos peixes. Quantificamos as quantidades semitotais de Ag, Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb e Zn no tecido muscular de peixes usando ICP-MS em um total de 255 indivíduos (representando 34 espécies), amostrados em locais não afetados e afetados ao longo da bacia do rio Doce. As concentrações de As e Hg foram maiores nos peixes dos locais afetados, provavelmente devido à mistura turbulenta de material previamente sedimentado pela onda gigante de rejeitos. As concentrações de Ag e Zn foram maiores nos peixes de locais não afetados. A concentração de As na espécie mais abundante nos locais não afetados e afetados (Geophagus brasiliensis) diminuiu com o aumento do peso dos peixes. A concentração de Cu e Zn diminuiu com o aumento do peso dos peixes, considerando toda a assembleia de espécies. O fluxo de lama de rejeitos aumentou a condutividade da água e a condutividade aumentou a concentração de Al nos peixes, portanto esperávamos uma maior concentração de Al nos peixes de locais afetados. No entanto, a concentração de Al observada nos peixes de locais afetados foi menor do que o esperado pela condutividade da água. Assim, o fluxo de lama de rejeitos reduziu a assimilação ou o acúmulo de Al nos peixes. O mercúrio diminuiu com o aumento da condutividade da água nos locais não afetados e afetados, considerando todas as espécies e também dentro de G. brasiliensis. Apesar da faixa de concentração relativamente baixa de metais nos peixes, os peixes de locais afetados pelo fluxo de lama de rejeitos de minério de ferro apresentaram maior concentração de As e Hg, em comparação com peixes de locais não afetados. A maior concentração de As e Hg nos locais afetados requer um monitoramento mais detalhado para garantir segurança alimentar em relação à atividade pesqueira ao longo do rio Doce. Integr Environ Assess Manag 2020;16:622-630.


Asunto(s)
Arsénico , Metales Pesados , Colapso de la Estructura , Contaminantes Químicos del Agua , Animales , Brasil , Monitoreo del Ambiente , Peces , Agua Dulce , Humanos , Metales Pesados/análisis , Músculos/química , Ríos , Contaminantes Químicos del Agua/análisis
4.
Zootaxa ; 4686(3): zootaxa.4686.3.2, 2019 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-31719477

RESUMEN

Lophotettiginae is a small, peculiar taxon of the Neotropical region, characterized mainly by median carina compresso-cristated or leaf-like crest, antennae flattened laterally and expanding from the base to the apex (incrassate shape). This subfamily has only one genus known as Lophotettix Hancock, 1909 that comprises five species. Here, we reviewed the types of the five known species, highlighting morphological aspects that distinguish the species from each other and from other tetrigids. Additionally, we also provide a pictorial identification key to Lophotettix species. Our results indicated that Lophotettiginae is a well-defined taxon and there are no synonyms among its species.


Asunto(s)
Ortópteros , Animales , Insectos
5.
Microsc Res Tech ; 81(2): 250-255, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29239112

RESUMEN

Identification Orphulellini grasshoppers (Acrididae: Gomphocerinae) species has been difficult due to high polymorphism rate. Orphulella Giglio-Tos, 1894 is a genus with widespread geographical distribution and poor descriptions. Orphulella punctata (De Geer, 1773) has an extensive record of occurrence and available information about the phallic complex, however, there is poor data describing other parts of the male reproductive tract. The objective of this study was characterizes the internal organs of the male reproductive system and spermatozoa of O. punctata. Orphulella punctata testes are of Fountain type, each having only four follicles. Spermatozoa into the seminal vesicle are arranged in bundles with c.a. 2320 µm length, with a nucleus 110 µm long. The spermatozoa are covered by a glycocalyx, the nucleus is cylindrical with condensed chromatin and connected to the flagellum by a dense and lamellar centriole adjunct. The axoneme have 9 + 9 + 2 pattern and present two symmetrical mitochondrial derivatives. A fibrous net and two flat membranous cisternae fill the space between the axoneme and mitochondrial derivatives. This is the first description of the reproductive system of a Gomphocerinae representative.


Asunto(s)
Genitales Masculinos/anatomía & histología , Saltamontes/anatomía & histología , Espermatozoides/ultraestructura , Animales , Axonema/ultraestructura , Núcleo Celular/ultraestructura , Glicocálix/ultraestructura , Masculino , Microscopía Electrónica de Transmisión , Especificidad de la Especie , Espermatogénesis , Testículo/anatomía & histología , Testículo/citología
6.
Zootaxa ; 4276(1): 96-106, 2017 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-28610217

RESUMEN

A new genus and a new species of Neotropical cricket is described: Pepoapua cariacica n. gen., n. sp., occurring in four Atlantic Forest remnants in the states of Bahia and Espírito Santo, Brazil. This new genus is morphologically similar in external characteristics, both male and female genitalia, with two other Neotropical genera of Nemobiinae: Amanayara and Kevanemobius. The combination of the external morphological characteristics, along with male genitalia, characterize a new genus through combination of the following characters: (i) males and females with morphologically similar tegmina; (ii) tegmina reduced, not reaching half of the second abdominal segment; (iii) dorsal field of the tegmina with parallel veins, without stridulatory vein or any specialized area for sound production; (iv) tibia of the first pair of legs without tympanum; (v) tibia of the third pair of legs with seven dorsal spurs, four inner and three outer, the proximo-dorsal inner spur reduced in size and the disto-dorsal inner spur without glandular aspect; (vi) ovipositor with distal portion of the dorsal and ventral valves serrated; (vii) male genitalia without evident bristles or sensillas; (viii) pseudepiphallic median lobe presenting apical and ventral projections.


Asunto(s)
Gryllidae , Distribución Animal , Estructuras Animales , Animales , Tamaño Corporal , Brasil , Femenino , Masculino , Tamaño de los Órganos
7.
Zookeys ; (702): 1-18, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29118597

RESUMEN

The tribe Cleostratini Bolívar, 1887 sensu Storozhenko, 2016 does not represent a monophyletic taxon because it gathers various Tetrigidae genera with various types of horn and prolongation of frons or vertex. Prolongation of these structures is present in morphologically and biogeographically distant groups. We do not regard Miriatrini Cadena-Castañeda & Cardona, 2015 synonymous with Cleostratini because the genus Miriatra Bolívar, 1906 belongs to a group of genera distant from Cleostratus Stål, 1877. There is no adequate diagnosis for proposed groups of genera forming tribes Cleostratini or Miriatrini. Miriatrini stat. resurr. are monotypic and include only Miriatra, Cleostratini are monotypic as well. Apteromystrum Storozhenko, 2016 syn. n. is regarded synonymous with Metopomystrum, M. apterumcomb. resurr., M. amazoniensiscomb. resurr. and Miriatra brevifastigiata (Cadena-Castañeda & Cardona, 2015), comb. n. are not Metopomystrum member. Herein a new species of pygmy unicorn, Metopomystrum muriciense Silva & Skejo, sp. n., is described from Atlantic Forest remnants in northeast of Brazil, collected on the Estação Serra do Ouro (municipality of Murici, Alagoas state). Distribution data, morphological characterization, and an identification key to Metopomystrum species are also presented.

8.
PLoS One ; 12(10): e0185800, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28977023

RESUMEN

For insects, choosing a favorable oviposition site is a type of parental care, as far as it increases the fitness of its offspring. Niche theory predicts that crickets should show a bell-shaped oviposition response to substrate moisture. However, lab experiments with mole crickets showed a linear oviposition response to substrate moisture. Studies with the house cricket Acheta domesticus also showed a linear juvenile body growth response to water availability, thus adult ovipositing females should respond positively to substrate moisture. We used a field experiment to evaluate the relationship between oviposition preference and substrate moisture in forest litter-dwelling cricket species. We also evaluated oviposition responses to substrate moisture level in Ubiquepuella telytokous, the most abundant litter cricket species in our study area, using a laboratory study. We offered cotton substrate for oviposition which varied in substrate moisture level from zero (i.e., dry) to maximum water absorption capacity. We used two complementary metrics to evaluate oviposition preference: (i) presence or absence of eggs in each sampling unit as binary response variable, and (ii) number of eggs oviposited per sampling unit as count response variable. To test for non-linear responses, we adjusted generalized additive models (GAMM) with mixed effects. We found that both cricket oviposition probability and effort (i.e., number of eggs laid) increased linearly with substrate moisture in the field experiment, and for U. telytokous in the lab experiment. We discarded any non-linear responses. Our results demonstrate the importance of substrate moisture as an ecological niche dimension for litter crickets. This work bolsters knowledge of litter cricket life history association with moisture, and suggests that litter crickets may be particularly threatened by changes in climate that favor habitat drying.


Asunto(s)
Gryllidae/fisiología , Oviposición , Animales , Femenino
9.
PLoS One ; 12(2): e0171336, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28158280

RESUMEN

Some ichneumonid wasps induce modifications in the web building behavior of their spider hosts to produce resistant "cocoon" webs. These structures hold and protect the wasp's cocoon during pupa development. The mechanism responsible for host manipulation probably involves the inoculation of psychotropic chemicals by the parasitoid larva during a specific developmental period. Recent studies indicate that some spiders build cocoon webs similar to those normally built immediately before ecdysis, suggesting that this substance might be a molting hormone or a precursor chemical of this hormone. Here, we report that Cyclosa spider species exhibiting modified behavior presented higher 20-OH-ecdysone levels than parasitized spiders acting normally or unparasitized individuals. We suggest that the lack of control that spiders have when constructing modified webs can be triggered by anachronic activation of ecdysis.


Asunto(s)
Arañas/fisiología , Avispas/fisiología , Animales , Control de la Conducta , Conducta Predatoria/fisiología
10.
Zootaxa ; 4126(2): 251-61, 2016 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-27395585

RESUMEN

Herein we describe a new species of Copiocerinae, Zygoclistron ruschii Silva n. sp., from Atlantic Forest remnants in southeastern Brazil, collected from the Reserva Biológica Augusto Ruschi in the Santa Teresa municipality, Espírito Santo state, Brazil. The diagnosis of this new species is based on phallic complex and terminalia characters.


Asunto(s)
Saltamontes/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Brasil , Ecosistema , Femenino , Bosques , Saltamontes/anatomía & histología , Saltamontes/crecimiento & desarrollo , Masculino , Tamaño de los Órganos
11.
PLoS One ; 10(10): e0139669, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26436669

RESUMEN

Crickets are often found feeding on fallen fruits among forest litter. Fruits and other sugar-rich resources are not homogeneously distributed, nor are they always available. We therefore expect that crickets dwelling in forest litter have a limited supply of sugar-rich resource, and will perceive this and displace towards resource-supplemented sites. Here we evaluate how sugar availability affects cricket species richness and abundance in old-growth Atlantic forest by spraying sugarcane syrup on leaf litter, simulating increasing availability, and collecting crickets via pitfall trapping. We found an asymptotic positive association between resource addition and species richness, and an interaction between resource addition and species identity on cricket abundance, which indicates differential effects of resource addition among cricket species. Our results indicate that 12 of the 13 cricket species present in forest litter are maintained at low densities by resource scarcity; this highlights sugar-rich resource as a short-term driver of litter cricket community structure in tropical forests. When resource was experimentally increased, species richness increased due to behavioral displacement. We present evidence that the density of many species is limited by resource scarcity and, when resources are added, behavioral displacement promotes increased species packing and alters species composition. Further, our findings have technical applicability for increasing sampling efficiency of local cricket diversity in studies aiming to estimate species richness, but with no regard to local environmental drivers or species-abundance characteristics.


Asunto(s)
Conducta Alimentaria , Gryllidae/fisiología , Sacarosa , Distribución Animal , Animales , Biodiversidad , Brasil , Dieta , Ecosistema , Preferencias Alimentarias , Bosques , Gryllidae/clasificación , Hojas de la Planta , Especificidad de la Especie
12.
PLoS One ; 10(9): e0137650, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26390400

RESUMEN

Stable isotope analysis (SIA) is an important tool for investigation of animal dietary habits for determination of feeding niche. Ideally, fresh samples should be used for isotopic analysis, but logistics frequently demands preservation of organisms for analysis at a later time. The goal of this study was to establish the best methodology for preserving forest litter-dwelling crickets for later SIA analysis without altering results. We collected two cricket species, Phoremia sp. and Mellopsis doucasae, from which we prepared 70 samples per species, divided among seven treatments: (i) freshly processed (control); preserved in fuel ethanol for (ii) 15 and (iii) 60 days; preserved in commercial ethanol for (iv) 15 and (v) 60 days; fresh material frozen for (vi) 15 and (vii) 60 days. After oven drying, samples were analyzed for δ15N, δ13C values, N(%), C(%) and C/N atomic values using continuous flow isotope ratio mass spectrometry. All preservation methods tested, significantly impacted δ13C and δ15N and C/N atomic values. Chemical preservatives caused δ13C enrichment as great as 1.5‰, and δ15N enrichment as great as 0.9‰; the one exception was M. doucasae stored in ethanol for 15 days, which had δ15N depletion up to 1.8‰. Freezing depleted δ13C and δ15N by up to 0.7 and 2.2‰, respectively. C/N atomic values decreased when stored in ethanol, and increased when frozen for 60 days for both cricket species. Our results indicate that all preservation methods tested in this study altered at least one of the tested isotope values when compared to fresh material (controls). We conclude that only freshly processed material provides adequate SIA results for litter-dwelling crickets.


Asunto(s)
Isótopos de Carbono/análisis , Gryllidae/química , Isótopos de Nitrógeno/análisis , Preservación Biológica/métodos , Animales
13.
Zootaxa ; 3974(1): 49-58, 2015 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-26249883

RESUMEN

Although male crickets provide more informative characters for the delimitation of species and genera, many taxonomic descriptions are based only on females. This is the case for Argizala Walker, 1869 and its two valid species, A. brasiliensis Walker, 1869 and A. hebardi Rehn, 1915. We provide herein a redescription of A. brasiliensis based on a male collected in the Pampa Biome, Capão do Leão municipality, Rio Grande do Sul State, Brazil. We present photographs of epitype and male genitalia, and discuss the diagnostic features of the genus and its morphological proximity to other Pteronemobiini Nearctic genera.


Asunto(s)
Gryllidae/clasificación , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Brasil , Femenino , Gryllidae/anatomía & histología , Gryllidae/crecimiento & desarrollo , Masculino , Tamaño de los Órganos
14.
Acta amaz ; 39(2): 459-466, 2009. graf, mapas, tab
Artículo en Portugués | LILACS | ID: lil-522395

RESUMEN

Vários pesquisadores têm avaliado impactos de estradas. Estes podem envolver aspectos paisagísticos, degradação do solo, poluição do ar e impactos sobre a fauna, como atropelamentos. Na estrada Raimundo Mascarenhas, que atravessa a Floresta Nacional de Carajás (ca. 400 mil hectares), há intenso tráfego de veículos automotores. O objetivo deste trabalho foi testar se há diferenças entre trechos da estrada, em três escalas espaciais; se há alteração ao longo dos anos; se alguns táxons são mais freqüentemente atropelados, e se a freqüência de atropelamentos aumenta com a precipitação mensal. Analisamos a freqüência de atropelamentos de vertebrados de abril/2003 até outubro/2006 ao longo dos 25 km iniciais da estrada. Registramos 155 atropelamentos. O número de atropelamentos diminui ao longo dos anos (P=0,01), e com a distância do início da estrada (P=0,0002). Serpentes (Ophidia) e gambás Didelphis marsupialis foram mais atropelados (7,5/ano), seguidos de aves, raposas Cerdocyon thous, quatis Nasua nasua, roedores (Rodentia), e não identificados (4,9/ano); cuíca Marmosops sp., tapeti Sylvilagus brasiliensis, guariba Alouatta sp., irara Eira barbara, jabuti Geochelone sp., lagartos (Lacertilia) e macaco prego Cebus apella (1/ano). Não houve relação significativa entre o número mensal de atropelamentos e a precipitação mensal.


Several researchers have evaluated impacts of highways. These can involve landscape aspects, soil degradation, air pollution, and impacts upon wildlife, such as roadkills. At the Raimundo Mascarenhas highway, that crosses the Carajás National Forest (ca. 400.000 ha), there is intense traffic of automotive vehicles. The aim of this work was to test if there were differences among higway sections on three spatial scales; if there was alteration along the years; if some taxa suffered more frequently roadkills; and if roadkill frequency increased with monthly precipitation. We analysed roadkill frequency of vertebrates from April/2003 to Octobre/2006 along the first 25 km of the highway. We registered 155 roadkills. The number of roadkills diminished along the years (P=0,01), and with distance from the beginning of the highway (P=0,0002). Snakes (Ophidia) and opossum Didelphis marsupialis presented higher roadkill numbers (7,5/year), followed by birds (Aves), crab-eating fox Cerdocyon thous, coati Nasua nasua, rodents (Rodentia), and non identified (4,9/year); opossum Marmosops sp., brazilian rabbit Sylvilagus brasiliensis, black howler monkey Alouatta sp., tayra Eira barbara, tortoise Geochelone sp., lizards (Lacertilia) e capuchin monkey Cebus apella (1/year). There was no significant relation between monthly roadkill numbers and monthly precipitation.


Asunto(s)
Accidentes de Tránsito , Ecosistema Amazónico , Fauna , Vehículos a Motor , Ambiente
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