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1.
Pap. avulsos zool ; 63: e202363002, 2023. mapas, ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1419202

Resumo

In Colombia, few studies have focused on nest architecture, behavior or sociality of wild bees. This study provides ba-sic information on the nests of Caenohalictus alexandrei and presents behavioral observations outside the nests, derived from direct field observation of 40 nests and 39 male sleeping cavities in two localities of the Savanna of Bogota, Colombia. We rec-ognized four different behavioral activities carried out by adult females: foraging, guarding, opening and closing of the en-trance of the nest, with foraging being the most frequent of them. The observed activities were carried out more frequently from 9:00 h to 13:00 h. Males were observed performing two behavioral activities in the sleeping cavities: staying at the cavity entrance and cavity departure. A third male activity, corporal grooming, was carried out outside the sleeping cavity. Our field observations indicate that more than one adult female was active simultaneously performing the different tasks within a sin-gle nest. The nests presented different levels of complexity in their architecture, depending on the age of the nest and num-ber of adult females in them. Descriptions of the nesting sites and behavioral activities as well as illustrations of the nest ar-chitecture are provided.(AU)


Assuntos
Animais , Masculino , Feminino , Ecossistema , Himenópteros/anatomia & histologia , Comportamento Animal , Colômbia
2.
Acta sci., Biol. sci ; 45: e63434, 2023. mapas, tab
Artigo em Inglês | VETINDEX | ID: biblio-1427142

Resumo

Faunal inventories are essential for biota management and conservation, especially in areas with potential for the creation of conservation units. Inventories of insect taxa such as dragonflies and damselflies (Odonata), which perform several environmental services in aquatic and terrestrial ecosystems, are of great importance. In view of the above, this study aimed to update and expand the list of Odonata species in the Barroso region, Minas Gerais State, Brazil. This study was carried out in three areas of forest fragments in Atlantic Forest and Cerrado biomes in October 2020, December 2020, January 2021, and March 2021. The sampling effort was 8 hours per day during 20 days, totaling 140 sampling hours. A total of 43 Odonata species were recorded, which increased the richness of the study area from 57 to 76 species. The studied areas harbor rare and endangered species. However, since the last sampling in 2009, there has been a significant reduction in diversity in the Atlantic Forest fragment. In view of the changes that forest fragments are undergoing, we underscore the need to create a conservation unit, especially in Baú Forest.(AU)


Assuntos
Animais , Biodiversidade , Odonatos/anatomia & histologia , Especificidade da Espécie , Brasil , Ecossistema
3.
Acta amaz ; 53(2): 141-153, 2023. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1428897

Resumo

Birds that inhabit white-sand ecosystems (WSE) in the Amazon are adapted to habitats distributed as isolated patches. These environments occur in sandy soils that are extremely poor in nutrients, have low floristic diversity and support bird assemblages restricted to WSE. We investigated whether bird species specialized in WSE have morphological or ecological traits that distinguish them from generalist birds that share the same habitat but are not restricted to WSE. We collected morphological and ecological data from 22 specialist and 102 generalist bird species from WSE and described their ecomorphological diversity using multivariate analyses and measures of functional diversity. Understory insectivorous species that move alone or in pairs, were the group with the most species among specialist birds from WSE. In contrast, canopy frugivorous species that form mono- or heterospecific groups were more frequent among generalist species. Specialist and generalist birds overlapped extensively in ecomorphological space, with specialists occupying a narrower space compared to generalists. Functional diversity, however, was not different between specialist and generalist species when controlling for the number of species within the communities. Further studies comparing the ecomorphological diversity of bird assemblages of other environments in the Amazon may highlight the ecological pressures leading to the functional diversity of specialist species in WSE observed in this study.(AU)


As aves que habitam os ecossistemas de areia branca (EAB) na Amazônia estão adaptadas a habitats distribuídos em manchas isoladas. Esses ambientes ocorrem em solos arenosos extremamente pobres em nutrientes, possuem baixa diversidade florística e suportam assembleias de aves restritas a EAB. Investigamos se espécies de aves especializadas em EAB possuem características morfológicas ou ecológicas que as distinguem de aves generalistas que compartilham o mesmo habitat, mas não estão restritas a EAB. Coletamos dados morfológicos e ecológicos de 22 espécies de aves especialistas e 102 generalistas de EAB, e descrevemos sua diversidade ecomorfológica usando análises multivariadas e medidas de diversidade funcional. Espécies insetívoras do sub-bosque que se movem solitárias ou em pares foram o grupo com maior número de espécies dentro das aves especialistas da EAB. Em contraste, espécies frugívoras de dossel que formam grupos mono ou heteroespecíficos foram mais frequentes entre as espécies generalistas. Aves especialistas e generalistas sobrepuseram-se extensivamente no espaço ecomorfológico, com especialistas ocupando um espaço mais estreito em comparação com generalistas. A diversidade funcional, no entanto, não foi diferente entre espécies especialistas e generalistas ao controlar o número de espécies dentro das comunidades. Estudos futuros comparando a diversidade ecomorfológica de assembleias de aves de outros ambientes na Amazônia podem destacar as pressões ecológicas que levam à diversidade funcional de espécies especialistas em EAB observadas neste estudo.(AU)


Assuntos
Animais , Aves/anatomia & histologia , Ecossistema Amazônico , Biodiversidade , Brasil , Análise Multivariada , Ecologia
4.
Neotrop. ichthyol ; 21(2): e220098, 2023. mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1435621

Resumo

Understanding patterns of freshwater fish assemblage structure is key to protect them from ongoing human-induced threats to aquatic biodiversity. Yet, studies on associations between fish assemblages and habitat are lacking from many areas of high diversity in Middle America. We assessed fish assemblage structure and environmental associations from a portion of the Lacantún River sub-basin (Usumacinta River, Chiapas, Mexico). Based on environmental data and 17,462 individuals (56 species, 46 genera, and 22 families) captured from 13 sites sampled between 2017­2019, we found that stream order, distance to the Usumacinta, forest cover, temperature, and dissolved oxygen are key to explaining assemblage composition. Four clusters were found via multivariate regression tree analysis, with stream order and dissolved oxygen as defining variables. Our findings suggest that fish communities remain spatially structured even at small scales, in association to environmental gradients among habitats.(AU)


Comprender los patrones de estructuración en los ensamblajes de peces dulceacuícolas es una clave para protegerlos de las amenazas humanas a la biodiversidad acuática. No obstante, los estudios sobre asociaciones entre ensamblajes de peces y su hábitat son aún escasos en muchas áreas de alta diversidad de América Media. Evaluamos las asociaciones entre la estructura de los ensamblajes de peces y el ambiente de una porción de la subcuenca del Río Lacantún (cuenca del Río Usumacinta, Chiapas, México). Con base en datos ambientales y un total de 17,462 individuos (56 especies, 46 géneros, y 22 familias) capturados de 13 sitios muestreados entre 2017­2019, encontramos que el orden del cauce, distancia al Usumacinta, cobertura vegetal, temperatura y oxígeno disuelto son clave para explicar la composición de los ensamblajes. Cuatro grupos se detectaron utilizando un árbol de regresión multivariada, definidos por el orden del cauce y el oxígeno disuelto como variables definitorias. Nuestros hallazgos sugieren que las comunidades de peces retienen su estructura espacial aún a pequeñas escalas, en asociación a gradientes ambientales entre hábitats.(AU)


Assuntos
Animais , Peixes/anatomia & histologia , Peixes/fisiologia , Padrões de Referência , Variação Genética , México
5.
Neotrop. ichthyol ; 20(2): e210051, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1375964

Resumo

South America is home to more miniature fishes (<26 mm in standard length) than any other continent. Despite this diversity, the ecology of miniature fishes is poorly studied. To promote the study of miniature fish ecology, we investigated patterns in total richness, assemblage structure and environmental correlates for miniature fishes in the rio Jacundá drainage of the Lower Amazon River basin, Pará State. Based on multi-pass dip-netting of leaf litter at 20 locations distributed across two sites, we collected miniature species and used rarefaction to estimate 9 to 14 species might be present. The miniature fish assemblage at the upstream site was a nested subset of the downstream site, and water pH and canopy cover, two features known to be altered by deforestation, correlated most strongly with assemblage variation. Our work represents one of the first quantitative assessments of environmental correlates with miniature fish assemblages and highlights research topics that should be investigated further to promote conservation and preservation of the overlooked and understudied Amazonian diminutive freshwater fish fauna.(AU)


A América do Sul abriga o maior número de peixes miniaturas (<26 mm de comprimento padrão) do que qualquer outro continente. Apesar dessa diversidade, a ecologia dos peixes miniaturas é pouco estudada. Visando promover estudos de ecologia de peixes miniaturas, investigamos padrões de riqueza total, estrutura da assembleia e fatores ambientais correlacionados para peixes miniaturas no rio Jacundá, drenagem do baixo rio Amazonas, Pará. Com base em múltiplas passagens de redes no sedimento em 20 pontos distribuídos em dois locais, coletamos espécies miniaturas e usamos rarefação para estimar que 9 a 14 espécies podem estar presentes. A assembleia de peixes miniaturas no local à montante foi um subgrupo aninhado na assembleia no local à jusante, e pH da água e cobertura de copas, dois fatores sabidamente alterados por desmatamento, foram os mais correlacionados com a variação na assembleia. Nosso trabalho representa um dos primeiros estudos quantitativos de fatores ambientais correlacionados às assembleias de peixes miniaturas e ressalta um tópico de pesquisa que deveria ser melhor investigado para promover a conservação da pouco conhecida fauna de peixes diminutos da Amazônia.(AU)


Assuntos
Animais , Biodiversidade , Ecologia , Peixes/anatomia & histologia , Biota
6.
Pap. avulsos zool ; 62: e202262060, 2022. ilus, mapas
Artigo em Inglês | VETINDEX | ID: biblio-1419153

Resumo

A new species of the recently described genus Habeas is described. The genus is the single urocoptid representant in Brazil. The new species is named as Habeas centroris, occurring in Paz de Salobro, Canarana, Bahia, Brazil. It is mainly characterized by its dense, delicate sculpture, peristome slightly centrally positioned. Its anatomy is similar to what is currently known, differing mainly by small pallial gland, short stomach, presence of anterior duct to digestive gland, vas deferens very posteriorly originated, prostate lying further the vas deferens origin, and visceral ganglia connected directly to pleural ganglia. The new species is another example of how weak the knowledge on the land mollusks in central Brazilian semi-dry region is, a biome that deserves protection.(AU)


Assuntos
Animais , Moluscos/anatomia & histologia , Moluscos/classificação , Especificidade da Espécie , Brasil , Ecossistema
7.
Pap. avulsos zool ; 62: e202262068, 2022. mapas, ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1419166

Resumo

The taxonomic status and anatomy of Leiosolenus (Labis) patagonicus (d'Orbigny, 1846 in 1834-1847) has been revised. This boring bivalve, belonging to the family Mytilidae, is the only Lithophaginae species distributed along the Argentinean coast. None of the fossil species mentioned for this area must be considered as a synonym of d'Orbigny´s species. Leiosolenus patagonicus is characterized by a thin shell, longitudinally elongated, with subterminal umbos and commarginal striae. The calcareous depositions on the outer surface of the shell are extended beyond the posterior margin. This species has well developed purple siphons, well differentiated morphologically from each other. Incurrent siphon is wider than excurrent, opened at the ventral edge and provided with a basal siphon valve at the base. Two pairs of demibranchs type B (1) from Atkins were observed. The shell characters and internal morphology were compared with other related species of the genus living along the South American coast. Finally, repository, type locality and habitat conditions were informed.(AU)


Assuntos
Animais , Mytilidae/anatomia & histologia , Mytilidae/classificação , Argentina , Ecossistema
8.
Ciênc. rural (Online) ; 52(8): e20210303, 2022. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1364730

Resumo

Morphometry of fruits and seeds is a useful and important information for phenotyping and genetic characterization of crop plant species and, for conservation of endangered species, as is the case of Butia purpurascens Glassman. In this study, we determined comparatively the morphometric features of fruits and pyrenes between yellow and magenta B. purpurascens morphotypes, located in four different sites (populations). We processed 1380 fruits collected from 69 individuals. We evaluated the length, width and weight of the fruits and pyrenes, the fresh and dry pulp mass, and percentage of pulp moisture. Yellow morph showed larger and heavier fruits than magenta morph. Morphometric differences were also evident among the four populations, suggesting that ecosystems fragmentation can cause deleterious genetic effects in B. purpurascens in long-term.


A morfometria de frutos e sementes é uma informação útil e importante para fenotipagem e caracterização genética de espécies vegetais com potencial econômico e, para a conservação de espécies ameaçadas, como é o caso de Butia purpurascens. Nesse estudo, determinamos comparativamente as características morfométricas de frutos e pirênios entre morfotipos amarelo e magenta de B. purpurascens, localizados em quatro localidades diferentes (populações). Beneficiamos 1380 frutos, coletados em 69 indivíduos. Avaliamos o comprimento, largura e o peso dos frutos e pirênios, a massa fresca e seca da polpa, e a porcentagem de umidade da polpa. O morfotipo amarelo apresentou frutos maiores e mais pesados do que o morfotipo magenta. Diferenças morfométricas também foram notórias entre as quatro populações, sugerindo que a fragmentação de ecossistemas pode causar efeitos genéticos deletérios em B. purpurascens ao longo do tempo.


Assuntos
Espécies em Perigo de Extinção , Arecaceae/anatomia & histologia , Arecaceae/genética , Ecossistema
9.
Acta sci., Biol. sci ; 44: e58763, mar. 2022. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1391174

Resumo

Anurans vary in body coloration and frequently exhibit color polymorphism, with selection by predation pressure favoring more cryptic animals. Spatial differentiation may also favor color polymorphism in some species, since cryptic morphotypes can use substrates that better match their coloration. Boana pulchella is a polymorphic species with green and brown morphotypes, but its polymorphism remains poorly understood. The aim of the present study was to determine the functionality of color polymorphism in B. pulchella as a defense strategy. Artificial green and brown clay models were placed in environments with green and brown background to determine if the two morphotypes of B. pulchella experience different frequencies of attacks. We expected that more conspicuous morphs are attacked more frequently. The attack rate, which suggests predation intent, on the models was 9.57%. The marks observed in the artificial models were left by both mammals and birds. The number of damaged models did not significantly differ between the different background environments. The results indicate that B. pulchella morphotypes are equally cryptic to predators in the studied environments. In conclusion, probably color polymorphism in B. pulchella is not operating as a defensive strategy, and other selective forces may be acting in the maintenance of color polymorphism in this species.(AU)


Assuntos
Animais , Masculino , Anuros/anatomia & histologia , Polimorfismo Genético/fisiologia , Morfogênese , Ecossistema , Modelos Anatômicos
10.
Acta sci., Biol. sci ; 44: e58699, mar. 2022. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1368121

Resumo

Paiche (Arapaima gigas) belongs to the Kingdom Animalia, Phylum Chordata, Class Actinopterygii, Order Osteoglossiformes, Family Arapaimidae, Genus Arapaima, and its origin may date to the Jurassic period. The species has natural habitat in the Amazonian rivers, found mainly in marginal lakes, being considered an important fishing resource, with high market value and high demand for meat and leather in both Brazilian and international trade. This study aims to report the morphology of the esophagus and stomach by light microscopy and scanning electronics microscopy. The esophagus was presented as muscular, short, tubular and fan-shaped in the cranial portion, also presenting deep longitudinal folds, and the entire mucosa is covered by mucus secretory cells with distinct morphological characteristics. Pirarurcu's stomach has a J-shape divided into three regions: cardiac with a lighter aspect, fundus portion with few folds in the mucosa, and pyloric with deeper folds, also presenting gastroliths in fundus and pyloric portions. Both microscopy studies highlighted three glandular regions, composed by mucoid columnar epithelial cells, gastric crypts with different shapes and sizes depending on each portion, in which the different shapes of the mucosal folds in each region of the stomach were evident, and digitiform microsaliences were found in the cardiac region, and micro-orifices and desmosome in the fundus region. Also, fundus and pyloric portions produce more mucus than the cardiac. Then morphology found was consistent with the eating habits and management of distinct characteristics of the digestive tract.(AU)


Assuntos
Animais , Ecossistema , Trato Gastrointestinal , Comportamento Alimentar , Perciformes/anatomia & histologia , Pesqueiros
11.
Zoologia (Curitiba, Impr.) ; 39: e21008, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1366063

Resumo

The importance of amphibian bioacoustics is widely documented in ecological, taxonomical and evolutionary studies, as calls might act as a primary mechanism of reproductive isolation. The influence of air temperature and male size on the variation of the advertisement calls in anurans is widely recognized but still insufficiently analyzed in Brazilian species. Our goals were to (1) describe the advertisement call of Aplastodiscus albosignatus (Lutz & Lutz, 1938), (2) test the influence of temperature and body size on its acoustic signals and (3) evaluate the variation of within and between-male acoustic signals. Advertisement calls of A. albosignatus consist of an unpulsed note with four harmonics. In most cases, the dominant frequency is the third harmonic but, in some calls, it was the minimum frequency (first harmonic). The average duration of calls was 0.191 s, the interval between calls was 2.08 s and the repetition rate was 33 calls per minute. On average, the minimum frequency was 550.15 Hz, the maximum frequency was 3531.70 Hz and the third harmonic was 2498.9 Hz. To evaluate the effect of air temperature, and body size on the variation of call parameters, we performed generalized linear models. The most explanatory model for spectral parameters was temperature plus body size. Concerning temporal variables, the best model that explains the variation in call duration was body size, while for the interval between calls was air temperature. The maximum frequency and the frequency of the third harmonic had little variation in the calls of both the same male and different males. Thus, these parameters were considered important in species recognition.(AU)


Assuntos
Animais , Masculino , Anuros/anatomia & histologia , Temperatura , Vocalização Animal/fisiologia , Tamanho Corporal/fisiologia
12.
Iheringia, Sér. zool ; 112: e2022004, 2022. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1370012

Resumo

As commonly observed in turtles, sexual size dimorphism (SSD) is pronounced in the Neotropical freshwater turtle Mesoclemmys vanderhaegei (Bour, 1973), a species in which females are usually larger than males. We studied SSD in two populations of M. vanderhaegei from the Brazilian Cerrado savannah, based on 245 specimens captured between November 2010 and August 2013. The carapace length of the largest male was 201 mm (9.15% shorter than that of the largest female, 220 mm). The mean sizes of males and females did not differ in the two populations. However, a comparison of eight selected morphological variables revealed that the size distribution pattern differed between the populations. Using model selection, seven out of 34 morphometric variables - from the head, plastron, bridge, and tail - were selected as the most suitable ones to distinguish between males and females. The pattern of SSD found in M. vanderhaegei is similar to that found in other chelonian species and may be the result of natural selection rather than ecological factors, since individuals of both sexes use the same habitats.


Como comumente observado em quelônios, dimorfismo sexual em tamanho (SSD) é pronunciado em Mesoclemmys vanderhaegei (Bour, 1973), uma espécie de quelônio Neotropical de água doce onde as fêmeas são geralmente maiores que os machos. Nós estudamos SSD em duas populações de M. vanderhaegei no Cerrado brasileiro, com base em 245 espécimes capturados entre novembro de 2010 e agosto de 2013. O comprimento da carapaça do maior macho foi de 201 mm (9,15% menor que o comprimento da maior fêmea, 220 mm). Os tamanhos médios de fêmeas e machos não diferiram nas duas populações. No entanto, uma comparação de oito variáveis morfológicas revelou que o padrão de distribuição de tamanhos diferiu entre as populações. Usando a seleção de modelos, sete das 34 variáveis morfométricas - incluindo medidas da cabeça, plastrão, ponte e cauda - foram selecionadas como as mais adequadas para distinguir fêmeas e machos. O padrão de SSD encontrado em M. vanderhaegei é similar ao encontrado em outras espécies de quelônios e pode ser o resultado de seleção natural ao invés de fatores ecológicos, uma vez que indivíduos de ambos os sexos usam os mesmos habitats.


Assuntos
Animais , Tartarugas/anatomia & histologia , Tartarugas/classificação , Caracteres Sexuais
13.
Pap. avulsos Zool. ; 61: e20216154, 2021. mapas, ilus, graf, tab
Artigo em Inglês | VETINDEX | ID: vti-32823

Resumo

The objective of this study was to describe the morphology and morphometry of saggitta otoliths of Polydactylus virginicus, Menticirrhus cuiaranensis and Conodon nobilis in a tropical environment. Fishes were caught with rod and reel in competitive fishing events promoted in 2014-2015 along the coast of Sergipe. A total of 174 pairs of sagitta otoliths of P. virginicus, 181 of M. cuiaranensis and 77 of C. nobilis was extracted. In general, the sagitta otoliths of all three species analyzed here presented different morphology and shape indices. The permutational multivariate analysis of variance (PERMANOVA) demonstrated significant differences among species and ontogenetic phases within each species using morphometry and shape indices. The linear discriminant analysis (LDA) presented a 98.3% correct reclassification of the otoliths by species.(AU)


Assuntos
Animais , Membrana dos Otólitos/anatomia & histologia , Perciformes/anatomia & histologia , Ecossistema , Análise Discriminante
14.
Acta sci., Biol. sci ; 43: e57072, 2021. map, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1461024

Resumo

The diversity of hawkmoths (Lepidoptera: Sphingidae) is poorly known in the biomes of the Bahia state. However, studies were carried out in other states of the northeastern region with species inventories in the Atlantic Forest, Caatinga and Cerrado. In order to broaden the knowledge on of the richness and diversity of hawkmoths in the Atlantic Forest of the state of Bahia, six monthly sampling sessions were carried out in the State Ecological Station of Wenceslau Guimarães. Hawkmoths were captured using a 250-watt mercury-vapor light trap set against a white cloth panel, for two nights a month, between 6:00 p.m. and 6:00 a.m. A total of 266 specimens were collected, distributed across 17 genera and 41 species. The most abundant and dominant species were Isognathus swainsoniC. Felder, 1862, with a relative abundance of 12.41%, and Xylophanes amadis(Cramer, 1782) andXylophanes anubus(Cramer, 1777), both with 7.9%. Our study represents the second inventory of hawkmoths for the state, totaling 59 species known for the Atlantic Forest of Bahia. Isognathus excelsior(Boisduval, [1875]) and Manduca lucetius(Cramer, 1780) represented new records for the biome. The accumulated number of species indicates the need for further sampling in order to safely reach the curve asymptote.


Assuntos
Animais , Ecossistema , Lepidópteros/anatomia & histologia , Lepidópteros/crescimento & desenvolvimento
15.
Acta Sci. Biol. Sci. ; 43: e57072, 2021. mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-32919

Resumo

The diversity of hawkmoths (Lepidoptera: Sphingidae) is poorly known in the biomes of the Bahia state. However, studies were carried out in other states of the northeastern region with species inventories in the Atlantic Forest, Caatinga and Cerrado. In order to broaden the knowledge on of the richness and diversity of hawkmoths in the Atlantic Forest of the state of Bahia, six monthly sampling sessions were carried out in the State Ecological Station of Wenceslau Guimarães. Hawkmoths were captured using a 250-watt mercury-vapor light trap set against a white cloth panel, for two nights a month, between 6:00 p.m. and 6:00 a.m. A total of 266 specimens were collected, distributed across 17 genera and 41 species. The most abundant and dominant species were Isognathus swainsoniC. Felder, 1862, with a relative abundance of 12.41%, and Xylophanes amadis(Cramer, 1782) andXylophanes anubus(Cramer, 1777), both with 7.9%. Our study represents the second inventory of hawkmoths for the state, totaling 59 species known for the Atlantic Forest of Bahia. Isognathus excelsior(Boisduval, [1875]) and Manduca lucetius(Cramer, 1780) represented new records for the biome. The accumulated number of species indicates the need for further sampling in order to safely reach the curve asymptote.(AU)


Assuntos
Animais , Lepidópteros/anatomia & histologia , Lepidópteros/crescimento & desenvolvimento , Ecossistema
16.
Pap. avulsos Zool. ; 61: e20216170, 2021. mapas, ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-33279

Resumo

The high mountain environment is a tough habitat that imposes many challenges to reptiles. As temperature decreases with altitude and has a dramatic variation throughout the day in the tropical mountains, ectotherms must cope with these harsh conditions. We studied the use of microhabitat and activity patterns of Stenocercus trachycephalus in the eastern Andes mountain range of Colombia. Three localities were sampled across the wide altitudinal distribution of this lizard species, in a range from 2,670 to 3,950 m a.s.l. The initial hypothesis was that these natural history traits would change with altitude but instead, we found that they remained roughly consistent, showing the great plasticity of this species. The results support that this lizard is a microhabitat-generalist using principally herb across the gradient, rarely shifting to specific plants or microhabitats such as rocks depending on availability. Regarding the activity pattern, this species was active throughout the day from 8:00 to 16:00 with a similar pattern along the gradient. Nevertheless, some differences were detected across localities. The activity pattern shifted from bimodal in the lower locality to unimodal in the higher ones. As expected, a correlation between temperature and activity patterns was found in one of the study sites. However, this was not the case for the lower and mid-elevation localities, where there was no correlation between these variables. The mid-elevation study site was the most interesting locality as the use of microhabitat relied virtually just on the herb stratum and the activity was constrained to the morning hours. These findings may be the result of the synergic effects of other ecological variables (weather variability, human impact, predation, population structure, or reproductive season). Our study gives the basis for a better understanding of how behavior (microhabitat choice and hours of activity) of ectotherms can help to counter thermal constraints in the neotropics when facing an altitudinal gradient. Further studies should focus on the thermal biology of this species, considering the influence of anthropic impact on these lizards populations.(AU)


Assuntos
Animais , Iguanas/anatomia & histologia , Iguanas/classificação , Ecossistema , Ecologia
17.
Pap. avulsos Zool. ; 61: e20216125, 2021. mapas, tab
Artigo em Inglês | VETINDEX | ID: vti-765690

Resumo

Conservation Units are an important tool for the Brazilian biota protection. However, various taxa, including the social wasps, are undersampled or are unknown in these areas. Therefore, our study aimed to assess the social wasp richness and distribution in the Conservation Units in Minas Gerais state, southeastern Brazil. The social wasps were sampled between 2015 and 2019 in the Ritápolis National Forest (FLONA Ritápolis), in the Alto-Montana Private Natural Heritage Reserve (RPPN Alto-Montana), in the Rio Machado Basin State Environmental Protection Area (APA Rio Machado) and in the Serra de São José Environmental Protection Area (APA Serra de São José), using two different sampling methodologies. Fourteen species were sampled for FLONA Ritápolis, 10 for RPPN Alto-Montana, 35 for APA Rio Machado and 19 for APA Serra de São José. Ninety-six social wasp species of the known richness in Minas Gerais were sampled in 14 Conservation Units, representing 90% of the fauna of the state. Thirty-four species are exclusive to these areas, with emphasis on the Rio Doce State Park, the Serra do Papagaio State Park, the Pandeiros River Wildlife Regufe and the APA Rio Machado. Most of the Conservation Units sampled are in the Atlantic Forest areas, but further efforts are needed in this biome, because of its accelerated destruction. There is still an urgent need for more studies in the Cerrado and Caatinga areas in the state, especially in Conservation Units.(AU)


Assuntos
Animais , Conservação dos Recursos Naturais , Vespas/anatomia & histologia , Vespas/classificação , Ecossistema
18.
Sci. agric ; 78(supl. 1): e20200173, 2021. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1498002

Resumo

Eucalypts are the most planted hardwood in the world, with 30 million ha. under cultivation. There are approximately 700 species of eucalypts, but more than 90 % of the plantations are concentrated in nine species of the Subgenus Symphyomyrtus in the Sections Exsertaria, Latoangulatae and Maidenaria. Since 2000, with the advancement of biotechnology, many species have been reclassified and regrouped according to their morphological and physiological characteristics, DNA structure and geographic distribution. This work had as its objective the formulation of a critical analysis which presents the main characteristics that will identify the species of Eucalyptus of these new sections. The species are classified mainly according to geographic distribution, where crosses occur; as evolution in the subgenus Symphyomyrtus is preferably reticulated (with backcrosses), which makes it difficult to identify the rate by molecular and morphological markers. Environmental ecological similarity will define whether the hybrid will become a new species or regress to one parent and become an ecotype. The hybrid will become a new species when it has ecological characteristics different from its parents.


Assuntos
Biotecnologia , Ecologia , Eucalyptus/anatomia & histologia , Eucalyptus/classificação
19.
Sci. agric. ; 78(supl. 1): e20200173, 2021. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-765604

Resumo

Eucalypts are the most planted hardwood in the world, with 30 million ha. under cultivation. There are approximately 700 species of eucalypts, but more than 90 % of the plantations are concentrated in nine species of the Subgenus Symphyomyrtus in the Sections Exsertaria, Latoangulatae and Maidenaria. Since 2000, with the advancement of biotechnology, many species have been reclassified and regrouped according to their morphological and physiological characteristics, DNA structure and geographic distribution. This work had as its objective the formulation of a critical analysis which presents the main characteristics that will identify the species of Eucalyptus of these new sections. The species are classified mainly according to geographic distribution, where crosses occur; as evolution in the subgenus Symphyomyrtus is preferably reticulated (with backcrosses), which makes it difficult to identify the rate by molecular and morphological markers. Environmental ecological similarity will define whether the hybrid will become a new species or regress to one parent and become an ecotype. The hybrid will become a new species when it has ecological characteristics different from its parents.(AU)


Assuntos
Eucalyptus/anatomia & histologia , Eucalyptus/classificação , Biotecnologia , Ecologia
20.
J. venom. anim. toxins incl. trop. dis ; 27: e20210002, 2021. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1340184

Resumo

Scorpions possess two systems of weapons: the pincers (chelae) and the stinger (telson). These are placed on anatomically and developmentally well separated parts of the body, that is, the oral appendages and at the end of the body axis. The otherwise conserved body plan of scorpions varies most in the shape and relative dimensions of these two weapon systems, both across species and in some cases between the sexes. We review the literature on the ecological function of these two weapon systems in each of three contexts of usage: (i) predation, (ii) defense and (iii) sexual contests. In the latter context, we will also discuss their usage in mating. We first provide a comparative background for each of these contexts of usage by giving examples of other weapon systems from across the animal kingdom. Then, we discuss the pertinent aspects of the anatomy of the weapon systems, particularly those aspects relevant to their functioning in their ecological roles. The literature on the functioning and ecological role of both the chelae and the telson is discussed in detail, again organized by context of usage. Particular emphasis is given on the differences in morphology or usage between species or higher taxonomic groups, or between genders, as such cases are most insightful to understand the roles of each of the two distinct weapon systems of the scorpions and their evolutionary interactions. We aimed to synthesize the literature while minimizing conjecture, but also to point out gaps in the literature and potential future research opportunities.(AU)


Assuntos
Animais , Estudos Ecológicos , Picadas de Escorpião
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