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1.
Anat Rec (Hoboken) ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39319398

RESUMO

The Mabuyinae subfamily exhibits remarkable diversity, encompassing 26 genera and 236 currently recognized species. Traditionally, the entire range of the group was attributed to the single genus Mabuya, which had a wide distribution along tropical regions of the Planet. In recent studies, phylogenetic hypotheses based on molecular data have identified four major groups, which have been further divided into geographically distinct clades. At least two phylogenetically distinct lineages of Mabuyinae are distributed in the Neotropical Region: Trachylepis atlantica and the remaining 16 genera within the Mabuyinae clade from the mainland and the Caribbean islands. Our understanding of Mabuyinae osteology is still quite limited, particularly concerning interspecific variation. This lack of information hinders our ability to make strong contributions to the phylogenetic relationships within this group or even to confirm the existence of certain new taxa considering their relatively conserved external morphology. This work provides a comprehensive anatomical reference for the adult skull of Neotropical Mabuyinae lizards, highlighting osteological features that might be useful for delimiting each genus. This descriptive guide includes illustrations and employs multiple techniques, such as dry preparation, clearing and staining, and high-resolution computerized microtomography. Our results provide additional diagnostic characteristics that include specific cranial bone arrangements, dental patterns, and cranial adaptations, such as dorsoventral head flattening, and their functional implications for bite force and cranial biomechanics. This study reinforces the importance of cranial morphology in understanding the phylogenetic relationships and evolutionary trajectories of New World Mabuyinae lizards, advocating for broader morphological sampling to enrich our understanding of these diverse reptiles.

2.
Zookeys ; 1134: 1-22, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761108

RESUMO

Glans penis morphology has been used as a powerful tool in mammal taxonomy to differentiate cryptic species. Neotropical rodent species Akodoncursor and A.montensis are cryptic, and interspecific hybrids are like their parental species. We investigated non-metric and metric phallic characters aiming to differentiate A.cursor from A.montensis. We also evaluated the parental species' influence of the phallic characters on hybrids. We analysed 96 male adults-56 A.cursor, 27 A.montensis, and 13 hybrids, subgrouping species by locality and hybrids by parental species (paternal vs maternal). We verified that A.cursor and A.montensis are distinguishable by penile-shape morphology: A.cursor has an elongated penile form with a flare in the distal portion and A.montensis has a barrel-shaped form. Also, dark spots in ventral view, if present in A.montensis, distinguish A.montensis from A.cursor. Although the non-metric characters differentiate the species, they do not distinguish the subgroups of A.cursor, A.montensis, and hybrids. The metric phallic characters indicated a significant difference between species and hybrids. These characters also differentiate the population groups of A.cursor. However, A.montensis subgroups and hybrids subgroups did not present a significant difference. This study shows the importance of penis morphology in the taxonomy of the cryptic rodent species A.cursor and A.montensis, representing a powerful tool to discriminate male specimens in mammal collections without karyotyping or sequencing, even though the specimens occurred in sympatric areas. Since most taxidermy protocols do not preserve the penis in mammal preparations, liquid preservation of some specimens or the removal of the penis before taxidermy for liquid preservation could be beneficial. We also recommend the organisation in museum collections of a penis bank for the A.cursor species group (or even all rodent species) to avoid losing this important information for species identification.

3.
Evolution ; 75(2): 427-436, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33314059

RESUMO

Despite considerable progress in recent decades in dissecting the genetic causes of natural morphological variation, there is limited understanding of how variation within species ultimately contributes to species differences. We have studied patterning of the non-sensory hairs, commonly known as "trichomes," on the dorsal cuticle of first-instar larvae of Drosophila. Most Drosophila species produce a dense lawn of dorsal trichomes, but a subset of these trichomes were lost in D. sechellia and D. ezoana due entirely to regulatory evolution of the shavenbaby (svb) gene. Here, we describe intraspecific variation in dorsal trichome patterns of first-instar larvae of D. virilis that is similar to the trichome pattern variation identified previously between species. We found that a single large effect QTL, which includes svb, explains most of the trichome number difference between two D. virilis strains and that svb expression correlates with the trichome difference between strains. This QTL does not explain the entire difference between strains, implying that additional loci contribute to variation in trichome numbers. Thus, the genetic architecture of intraspecific variation exhibits similarities and differences with interspecific variation that may reflect differences in long-term and short-term evolutionary processes.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/genética , Drosophila/genética , Larva/anatomia & histologia , Locos de Características Quantitativas , Fatores de Transcrição/genética , Animais , Drosophila/anatomia & histologia , Feminino , Masculino , Fenótipo , Polimorfismo Genético , Sequências Reguladoras de Ácido Nucleico/genética , Especificidade da Espécie
4.
Neotrop Entomol ; 49(5): 668-676, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32578047

RESUMO

The foraging behavior of social wasps may vary throughout the day in response to different factors, including environmental variation and interspecific interactions. Body size is known to play a critical role in determining daily activity patterns in ecological communities. However, the body size characteristics of most species of social wasps is poorly known, as well the relationship between body size and foraging schedules. In this study, we evaluated the extent to which body size determines the patterns of daily activity in a community of social wasps. We found a high temporal overlap in most of the species pairs tested. The pattern of daily foraging activity fits a bimodal distribution for the majority of the species. Moreover, we found a relationship between body and foraging time; in general, smaller species tended to begin foraging in the early hours of the morning, in contrast to larger wasps, which began foraging later. These results suggest that patterns of foraging activity in social wasps are likely to be the result of complex interactions between many different factors, including body size.


Assuntos
Comportamento Apetitivo , Tamanho Corporal , Vespas/fisiologia , Animais , Brasil , Periodicidade , Comportamento Social , Vigna , Vespas/classificação
5.
J Morphol ; 281(6): 620-635, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32383531

RESUMO

Mating plugs have been proposed as a mechanism that has evolved to avoid sperm competition. Their structure and composition vary across taxa and are related to the effectiveness of its function. This effectiveness could be related to different evolutionary interests of the sexes. Urophonius brachycentrus and Urophonius achalensis (Scorpiones, Bothriuridae) are highly suitable species to study mating plugs because both are monandrous species with specific morphological and physiological responses in the female's genitalia. Here, we analyze (a) the morphology and fine structure of the mating plugs of both species, (b) the site of production in males and the formation process of the mating plug, and (c) the changes that it undergoes over time in the female's reproductive tract. In both species, a complex mating plug obliterates the female's genital aperture and fills the genital atrium. We observed considerable interspecific variation in the mating plug morphology. A mating hemi-plug was found surrounding the capsular lobes of the hemispermatophore, which could have a mixed composition (involving portions of the hemispermatophore and glandular products). The glandular portion was transferred in a semi-solid state filling the female's genital atrium and then hardening. Changes that the plug undergoes in the female's genitalia (darkening and increase of the "distal" area of the plug) indicate a participation of the female to the formation of this type of plug. Our study provides new insights into the plugging phenomenon in scorpions, and we discussed the adaptive significance as a post-copulatory mechanism to avoid sperm competition.


Assuntos
Genitália/anatomia & histologia , Escorpiões/anatomia & histologia , Comportamento Sexual Animal/fisiologia , Animais , Feminino , Genitália/diagnóstico por imagem , Genitália/ultraestrutura , Imageamento Tridimensional , Masculino , Escorpiões/ultraestrutura , Especificidade da Espécie
6.
Ecology ; 100(6): e02647, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30845354

RESUMO

Scientists have long been trying to understand why the Neotropical region holds the highest diversity of birds on Earth. Recently, there has been increased interest in morphological variation between and within species, and in how climate, topography, and anthropogenic pressures may explain and affect phenotypic variation. Because morphological data are not always available for many species at the local or regional scale, we are limited in our understanding of intra- and interspecies spatial morphological variation. Here, we present the ATLANTIC BIRD TRAITS, a data set that includes measurements of up to 44 morphological traits in 67,197 bird records from 2,790 populations distributed throughout the Atlantic forests of South America. This data set comprises information, compiled over two centuries (1820-2018), for 711 bird species, which represent 80% of all known bird diversity in the Atlantic Forest. Among the most commonly reported traits are sex (n = 65,717), age (n = 63,852), body mass (n = 58,768), flight molt presence (n = 44,941), molt presence (n = 44,847), body molt presence (n = 44,606), tail length (n = 43,005), reproductive stage (n = 42,588), bill length (n = 37,409), body length (n = 28,394), right wing length (n = 21,950), tarsus length (n = 20,342), and wing length (n = 18,071). The most frequently recorded species are Chiroxiphia caudata (n = 1,837), Turdus albicollis (n = 1,658), Trichothraupis melanops (n = 1,468), Turdus leucomelas (n = 1,436), and Basileuterus culicivorus (n = 1,384). The species recorded in the greatest number of sampling localities are Basileuterus culicivorus (n = 243), Trichothraupis melanops (n = 242), Chiroxiphia caudata (n = 210), Platyrinchus mystaceus (n = 208), and Turdus rufiventris (n = 191). ATLANTIC BIRD TRAITS (ABT) is the most comprehensive data set on measurements of bird morphological traits found in a biodiversity hotspot; it provides data for basic and applied research at multiple scales, from individual to community, and from the local to the macroecological perspectives. No copyright or proprietary restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications or teaching and educational activities.

7.
PeerJ ; 7: e6601, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30886780

RESUMO

BACKGROUND: Geographic variation in body size and condition can reveal differential local adaptation to resource availability or climatic factors. Body size and condition are related to fitness in garter snakes (Thamnophis), thus good body condition may increase survival, fecundity in females, and mating success in males. Phylogenetically related species in sympatry are predicted to exhibit similar body condition when they experience similar environmental conditions. We focused on interspecific and geographical variation in body size and condition in three sympatric Mexican garter snakes from the highlands of Central Mexico. METHODS: We assessed SVL, mass, and body condition (obtained from Major axis linear regression of ln-transformed body mass on ln-transformed SVL) in adults and juveniles of both sexes of Thamnophis eques, T. melanogaster, and T. scalaris sampled at different locations and ranges from 3-11 years over a 20-year period. RESULTS: We provide a heterogeneous pattern of sexual and ontogenic reproductive status variations of body size and condition among local populations. Each garter snake species shows locations with good and poor body condition; juvenile snakes show similar body condition between populations, adults show varying body condition between populations, and adults also show sex differences in body condition. We discuss variations in body condition as possibly related to the snakes' life cycle differences.

8.
Neotrop. ichthyol ; 17(3): e190057, 2019. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-25105

RESUMO

Bryconamericus is a highly diverse group of characid fishes, being cytogenetic a valuable tool for the delimitation of species. Bryconamericus aff. iheringii (Upper Uruguay/Lower Paraná), B. coeruleus (Upper Paraná), B. cf. ecai e B. cf. eigenmanni (Upper Uruguay) were studied cytogenetically, and presented 2n=52 chromosomes, with interpopulational/interspecific variation of karyotype and fundamental number. Heterochromatin was evidenced in pericentromeric, telomeric and interstitial regions, and it was shown to be an important cytogenetic marker. Single nucleolar organizing regions (NORs) were found in B. cf. eigenmanni, B. cf. ecai and B. aff. iheringii (Lower Paraná), and multiple in B. aff. iheringii (Upper Uruguay) and B. coeruleus, with occurrence of two patterns for the first species, and three for the second. The 5S/18S rDNA-FISH confirmed the location of the NORs and showed single 5S rDNA cistrons only in B. aff. iheringii (Lower Paraná), evidencing the dispersion of both genes, often co-located, in the karyotype of the others species. The data of this work contribute for the delimitation of the species of the genus. Co-localization of ribosomal genes may represent a plesiomorphic condition for the group, and their dispersion suggest the occurrence of duplication, pseudogeneization and transposition events mediated by mobile genetic elements.(AU)


Bryconamericus é um grupo altamente diverso de caracídeos, sendo a citogenética uma valiosa ferramenta para a delimitação de espécies. Bryconamericus aff. iheringii (Alto Uruguai/Baixo Paraná), B. coeruleus (Alto Paraná), B. cf. ecai e B. cf. eigenmanni (Alto Uruguai) foram estudados citogeneticamente, e apresentaram 2n=52 cromossomos, com variação interpopulacional/interespecífica de cariótipo e número fundamental (NF). Heterocromatinas foram evidenciadas nas regiões pericentromérica, telomérica e intersticial, e mostrou-se um importante marcador citogenético. Regiões organizadores de nuclcéolos (RONs) simples foram encontradas em B. cf. eigenmanni, B. cf. ecai e B. aff. iheringii (Baixo Paraná), e múltiplas em B. aff. iheringii (Alto Uruguai) e em B. coeruleus, com a ocorrência de dois padrões de localização para a primeira espécie, e três para a segunda. A FISH-DNAr 5S/18S confirmou a localização das RONs e mostrou cístrons simples de DNAr 5S apenas em B. aff. iheringii (Baixo Paraná), evidenciando a dispersão de ambos os genes, muitas vezes co-localizados, no cariótipo das demais espécies. Os dados deste trabalho contribuem para a delimitação das espécies do gênero. A co-localização dos genes ribossomais pode representar uma condição plesiomórfica para o grupo, e sua dispersão sugere a ocorrência de eventos de duplicação, pseudogenização e transposição mediada por elementos genéticos móveis.(AU)


Assuntos
Transferência Genética Horizontal , Citogenética/métodos , Characidae/genética , DNA Ribossômico , Marcadores Genéticos
9.
Neotrop. ichthyol ; 17(3): e190057, 2019. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1040657

RESUMO

Bryconamericus is a highly diverse group of characid fishes, being cytogenetic a valuable tool for the delimitation of species. Bryconamericus aff. iheringii (Upper Uruguay/Lower Paraná), B. coeruleus (Upper Paraná), B. cf. ecai e B. cf. eigenmanni (Upper Uruguay) were studied cytogenetically, and presented 2n=52 chromosomes, with interpopulational/interspecific variation of karyotype and fundamental number. Heterochromatin was evidenced in pericentromeric, telomeric and interstitial regions, and it was shown to be an important cytogenetic marker. Single nucleolar organizing regions (NORs) were found in B. cf. eigenmanni, B. cf. ecai and B. aff. iheringii (Lower Paraná), and multiple in B. aff. iheringii (Upper Uruguay) and B. coeruleus, with occurrence of two patterns for the first species, and three for the second. The 5S/18S rDNA-FISH confirmed the location of the NORs and showed single 5S rDNA cistrons only in B. aff. iheringii (Lower Paraná), evidencing the dispersion of both genes, often co-located, in the karyotype of the others species. The data of this work contribute for the delimitation of the species of the genus. Co-localization of ribosomal genes may represent a plesiomorphic condition for the group, and their dispersion suggest the occurrence of duplication, pseudogeneization and transposition events mediated by mobile genetic elements.(AU)


Bryconamericus é um grupo altamente diverso de caracídeos, sendo a citogenética uma valiosa ferramenta para a delimitação de espécies. Bryconamericus aff. iheringii (Alto Uruguai/Baixo Paraná), B. coeruleus (Alto Paraná), B. cf. ecai e B. cf. eigenmanni (Alto Uruguai) foram estudados citogeneticamente, e apresentaram 2n=52 cromossomos, com variação interpopulacional/interespecífica de cariótipo e número fundamental (NF). Heterocromatinas foram evidenciadas nas regiões pericentromérica, telomérica e intersticial, e mostrou-se um importante marcador citogenético. Regiões organizadores de nuclcéolos (RONs) simples foram encontradas em B. cf. eigenmanni, B. cf. ecai e B. aff. iheringii (Baixo Paraná), e múltiplas em B. aff. iheringii (Alto Uruguai) e em B. coeruleus, com a ocorrência de dois padrões de localização para a primeira espécie, e três para a segunda. A FISH-DNAr 5S/18S confirmou a localização das RONs e mostrou cístrons simples de DNAr 5S apenas em B. aff. iheringii (Baixo Paraná), evidenciando a dispersão de ambos os genes, muitas vezes co-localizados, no cariótipo das demais espécies. Os dados deste trabalho contribuem para a delimitação das espécies do gênero. A co-localização dos genes ribossomais pode representar uma condição plesiomórfica para o grupo, e sua dispersão sugere a ocorrência de eventos de duplicação, pseudogenização e transposição mediada por elementos genéticos móveis.(AU)


Assuntos
Transferência Genética Horizontal , Citogenética/métodos , Characidae/genética , DNA Ribossômico , Marcadores Genéticos
10.
Ecology ; 99(2): 498, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29399824

RESUMO

Measures of traits are the basis of functional biological diversity. Numerous works consider mean species-level measures of traits while ignoring individual variance within species. However, there is a large amount of variation within species and it is increasingly apparent that it is important to consider trait variation not only between species, but also within species. Mammals are an interesting group for investigating trait-based approaches because they play diverse and important ecological functions (e.g., pollination, seed dispersal, predation, grazing) that are correlated with functional traits. Here we compile a data set comprising morphological and life history information of 279 mammal species from 39,850 individuals of 388 populations ranging from -5.83 to -29.75 decimal degrees of latitude and -34.82 to -56.73 decimal degrees of longitude in the Atlantic forest of South America. We present trait information from 16,840 individuals of 181 species of non-volant mammals (Rodentia, Didelphimorphia, Carnivora, Primates, Cingulata, Artiodactyla, Pilosa, Lagomorpha, Perissodactyla) and from 23,010 individuals of 98 species of volant mammals (Chiroptera). The traits reported include body mass, age, sex, reproductive stage, as well as the geographic coordinates of sampling for all taxa. Moreover, we gathered information on forearm length for bats and body length and tail length for rodents and marsupials. No copyright restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data.

11.
Neotrop Entomol ; 46(1): 8-17, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27457373

RESUMO

Wasps are able to synthesize toxic compounds known as venoms, which form a part of a mechanism to overcome prey and also to defend their colonies. Study of the compounds that constitute these substances is essential in order to understand how this defense mechanism evolved, since there is evidence that the venoms can vary both intra- and interspecifically. Some studies have used liquid and gas chromatography as a reliable technique to analyze these compounds. However, the use of Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) to analyze the variations in venom's chemical profile has been proposed recently. This study evaluated whether the FTIR-PAS technique is effective for assessing the role of environmental factors on intra- and interspecific differences in the venom of the wasps Polybia paulista Von Ihering and Polybia occidentalis Olivier by FTIR-PAS. The colonies were collected in three municipalities of Mato Grosso do Sul, Brazil, in different types of environments. The results showed that the venoms of P. paulista and P. occidentalis differed significantly in profile. In addition, the intraspecific differences in the venom's chemical profile of P. paulista are related to the type of environment where they nested, regardless of the geographical distance between the nests. The FTIR-PAS technique proved to be reliable and effective to evaluate the variations in the venom's chemical profile in social wasps.


Assuntos
Peçonhas/química , Vespas , Animais , Brasil , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Ann Bot ; 114(3): 435-40, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25006181

RESUMO

BACKGROUND AND AIMS: Vulnerability of the leaf hydraulic pathway to water-stress-induced dysfunction is a key component of drought tolerance in plants and may be important in defining species' climatic range. However, the generality of the association between leaf hydraulic vulnerability and climate across species and sites remains to be tested. METHODS: Leaf hydraulic vulnerability to drought (P50leaf, the water potential inducing 50 % loss in hydraulic function) was measured in a diverse group of 92 woody, mostly evergreen angiosperms from sites across a wide range of habitats. These new data together with some previously published were tested against key climate indices related to water availability. Differences in within-site variability in P50leaf between sites were also examined. KEY RESULTS: Values of hydraulic vulnerability to drought in leaves decreased strongly (i.e. became more negative) with decreasing annual rainfall and increasing aridity across sites. The standard deviation in P50leaf values recorded within each site was positively correlated with increasing aridity. P50leaf was also a good indicator of the climatic envelope across each species' distributional range as well as their dry-end distributional limits within Australia, although this relationship was not consistently detectable within sites. CONCLUSIONS: The findings indicate that species sorting processes have influenced distributional patterns of P50leaf across the rainfall spectrum, but alternative strategies for dealing with water deficit exist within sites. The strong link to aridity suggests leaf hydraulic vulnerability may influence plant distributions under future climates.


Assuntos
Secas , Magnoliopsida/fisiologia , Folhas de Planta/fisiologia , Transpiração Vegetal , Água/metabolismo , Austrália , Clima , Ecossistema , Peru , Árvores/fisiologia
13.
Neotrop. ichthyol ; 10(2): 417-424, 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-640797

RESUMO

The rio das Velhas, located in central Minas Gerais State (Brazil), is a major tributary of the rio São Francisco. Despite several anthropogenic pressures, this basin supports more than 115 fish species. The aim of this study was to compare the morphological space occupied by fish assemblages in four regions (headwaters, upper, middle, and lower course) along the channel of the rio das Velhas. We try to answer the following question: Is there a change in the morphological organization of the fish along the longitudinal gradient of the river? Individuals from 67 species, collected at several sites in the basin from 1999 to 2008, were measured for 11 morphological attributes related to swimming behavior and habitat use. Through the graphs, the first two dimensions of the PCA suggest that the morphological volume occupied by the headwaters region is smaller than the other sections, because of the low richness of the site. However, morphological hypervolumes of the four reaches analyzed by Euclidean distances were not statistically different. The results indicated that only the density of morphological types increases along the rio das Velhas, and there is no difference between the headwaters and upper courses. Therefore, in order to use functional groups related to the morphology of the species as tools to take measures for the conservation and revitalization of the rio das Velhas, it is necessary analyze the density of species within these groups, as well as their composition.


O rio das Velhas, localizado na região central do estado de Minas Gerais (Brasil), é o mais extenso tributário do rio São Francisco. Apesar dos inúmeros impactos antrópicos que sofre, sua bacia abriga uma rica ictiofauna, com mais de 115 espécies conhecidas. O objetivo deste estudo foi comparar o espaço morfológico ocupado pelas assembleias de peixes em quatro regiões (cabeceira, alto curso, médio curso e baixo curso) ao longo da calha do rio das Velhas. Procuramos responder a seguinte pergunta: há uma mudança na organização morfológica da comunidade de peixes ao longo do gradiente longitudinal do rio? Indivíduos de 67 espécies, coletados em diversos trechos da bacia entre 1999 e 2008, foram medidos considerando 11 atributos morfológicos relacionados ao comportamento natatório e uso do habitat. Graficamente, as duas primeiras dimensões da PCA sugerem que o volume morfológico ocupado pela região de cabeceira é menor do que o dos demais trechos, devido à baixa riqueza do local. Entretanto, os hipervolumes morfológicos dos quatro trechos analisados por meio das distancias euclidianas não diferiram estatisticamente. Os resultados indicaram que apenas a densidade de tipos morfológicos aumenta ao longo do rio das Velhas, sendo que não há diferença entre a cabeceira e o alto curso. Portanto, para o uso de grupos funcionais relacionados à morfologia das espécies como ferramentas para tomada de medidas que visem à conservação e revitalização do rio das Velhas, é necessária a abordagem da densidade de espécies dentro destes grupos, assim como sua composição.


Assuntos
Biodiversidade , /análise , Distribuição Animal/classificação , Peixes/anatomia & histologia , Fauna Aquática/análise , Peixes/crescimento & desenvolvimento
14.
Neotrop. ichthyol ; 10(2): 417-424, 2012. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-8752

RESUMO

The rio das Velhas, located in central Minas Gerais State (Brazil), is a major tributary of the rio São Francisco. Despite several anthropogenic pressures, this basin supports more than 115 fish species. The aim of this study was to compare the morphological space occupied by fish assemblages in four regions (headwaters, upper, middle, and lower course) along the channel of the rio das Velhas. We try to answer the following question: Is there a change in the morphological organization of the fish along the longitudinal gradient of the river? Individuals from 67 species, collected at several sites in the basin from 1999 to 2008, were measured for 11 morphological attributes related to swimming behavior and habitat use. Through the graphs, the first two dimensions of the PCA suggest that the morphological volume occupied by the headwaters region is smaller than the other sections, because of the low richness of the site. However, morphological hypervolumes of the four reaches analyzed by Euclidean distances were not statistically different. The results indicated that only the density of morphological types increases along the rio das Velhas, and there is no difference between the headwaters and upper courses. Therefore, in order to use functional groups related to the morphology of the species as tools to take measures for the conservation and revitalization of the rio das Velhas, it is necessary analyze the density of species within these groups, as well as their composition.(AU)


O rio das Velhas, localizado na região central do estado de Minas Gerais (Brasil), é o mais extenso tributário do rio São Francisco. Apesar dos inúmeros impactos antrópicos que sofre, sua bacia abriga uma rica ictiofauna, com mais de 115 espécies conhecidas. O objetivo deste estudo foi comparar o espaço morfológico ocupado pelas assembleias de peixes em quatro regiões (cabeceira, alto curso, médio curso e baixo curso) ao longo da calha do rio das Velhas. Procuramos responder a seguinte pergunta: há uma mudança na organização morfológica da comunidade de peixes ao longo do gradiente longitudinal do rio? Indivíduos de 67 espécies, coletados em diversos trechos da bacia entre 1999 e 2008, foram medidos considerando 11 atributos morfológicos relacionados ao comportamento natatório e uso do habitat. Graficamente, as duas primeiras dimensões da PCA sugerem que o volume morfológico ocupado pela região de cabeceira é menor do que o dos demais trechos, devido à baixa riqueza do local. Entretanto, os hipervolumes morfológicos dos quatro trechos analisados por meio das distancias euclidianas não diferiram estatisticamente. Os resultados indicaram que apenas a densidade de tipos morfológicos aumenta ao longo do rio das Velhas, sendo que não há diferença entre a cabeceira e o alto curso. Portanto, para o uso de grupos funcionais relacionados à morfologia das espécies como ferramentas para tomada de medidas que visem à conservação e revitalização do rio das Velhas, é necessária a abordagem da densidade de espécies dentro destes grupos, assim como sua composição.(AU)


Assuntos
Peixes/anatomia & histologia , Biodiversidade , /análise , Distribuição Animal/classificação , Peixes/crescimento & desenvolvimento , Fauna Aquática/análise
15.
Chiropt. neotrop. ; 16(2): 762-768, 2010.
Artigo em Português | VETINDEX | ID: vti-464670

RESUMO

Even though it is abundant throughout its distribution range, Myotis levis (I. Geoffroy, 1824) is a poorly-known species. Field efforts were carried out in the present study to better understand some aspects of this species natural history on the shelter (house shelter). Information was obtained through captures using mist-nets positioned at the exit of an artificial shelter, during three consecutive nights, as well as incursions into the shelter, with the goal of estimating the number of individuals in the colony. The study area is located within the Palmas Grasslands, Palmas Municipality, southern Paraná (26º3459S and 51º3616W). Captures resulted in 186 individuals, being 96 adults and 90 juveniles. The colony size was estimated in circa of 12 000 and 15 000 individuals. Based on the structure of the population, the presence of reproductive females, juveniles, and infants, a nursery colony was characterized. In addition to aspects of their reproductive biology, this study deals also morphometric and coloration variations, as well as two cases of partial albinism.


A despeito de ser abundante em sua área de distribuição, a biologia de Myotis levis (I. Geoffroy, 1824) é pouco conhecida. Realizou-se uma campanha de campo com o objetivo de melhor conhecer alguns aspectos da história natural dessa espécie, em um abrigo (forro de casa). Coletaram-se informações através de capturas com redes de neblina posicionadas à saída do abrigo, durante três noites consecutivas, além de incursões feitas dentro do mesmo, com objetivo de fazer uma estimativa do número de indivíduos na colônia. A área de estudo situa-se nos Campos de Palmas, Município de Palmas, Sul do Paraná (26º3459S e 51º3616W). Foram capturados 186 indivíduos, sendo 96 adultos e 90 juvenis. O número de morcegos foi estimado entre 12 000 e 15 000 indivíduos. Pela estrutura da população, presença de fêmeas reprodutivas, juvenis e infantes caracterizou-se uma colônia maternidade. Além de aspectos da biologia reprodutiva, esse trabalho descreve variações morfométricas e de coloração e registra dois casos de albinismo parcial.

16.
Chiropt. Neotrop. (Impr.) ; 16(2): 762-768, 2010.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1471938

RESUMO

Even though it is abundant throughout its distribution range, Myotis levis (I. Geoffroy, 1824) is a poorly-known species. Field efforts were carried out in the present study to better understand some aspects of this species natural history on the shelter (house shelter). Information was obtained through captures using mist-nets positioned at the exit of an artificial shelter, during three consecutive nights, as well as incursions into the shelter, with the goal of estimating the number of individuals in the colony. The study area is located within the Palmas Grasslands, Palmas Municipality, southern Paraná (26º3459S and 51º3616W). Captures resulted in 186 individuals, being 96 adults and 90 juveniles. The colony size was estimated in circa of 12 000 and 15 000 individuals. Based on the structure of the population, the presence of reproductive females, juveniles, and infants, a nursery colony was characterized. In addition to aspects of their reproductive biology, this study deals also morphometric and coloration variations, as well as two cases of partial albinism.


A despeito de ser abundante em sua área de distribuição, a biologia de Myotis levis (I. Geoffroy, 1824) é pouco conhecida. Realizou-se uma campanha de campo com o objetivo de melhor conhecer alguns aspectos da história natural dessa espécie, em um abrigo (forro de casa). Coletaram-se informações através de capturas com redes de neblina posicionadas à saída do abrigo, durante três noites consecutivas, além de incursões feitas dentro do mesmo, com objetivo de fazer uma estimativa do número de indivíduos na colônia. A área de estudo situa-se nos Campos de Palmas, Município de Palmas, Sul do Paraná (26º3459S e 51º3616W). Foram capturados 186 indivíduos, sendo 96 adultos e 90 juvenis. O número de morcegos foi estimado entre 12 000 e 15 000 indivíduos. Pela estrutura da população, presença de fêmeas reprodutivas, juvenis e infantes caracterizou-se uma colônia maternidade. Além de aspectos da biologia reprodutiva, esse trabalho descreve variações morfométricas e de coloração e registra dois casos de albinismo parcial.

17.
Genet. mol. res. (Online) ; Genet. mol. res. (Online);7(2): 559-566, 2008. tab, ilus
Artigo em Inglês | LILACS | ID: lil-640981

RESUMO

We have been able to discriminate different castes and sexes of ants in the same colony by measuring cuticular hydrocarbon levels with Fourier transform infrared photoacoustic spectroscopy, compared by canonical discriminant function analysis. We have now applied this methodology to various colonies of two species of ants of the genus Ectatomma in the Brazilian Cerrado. There were clear interspecific differences in cuticular hydrocarbons of these ants, with a small intraspecific variation. The differences between colonies were greater in E. brunneum than in E. vizottoi. Genetic differences among the colonies and species were well estimated by Fourier transform infrared photoacoustic spectroscopy and statistical analyses.


Assuntos
Animais , Formigas/química , Hidrocarbonetos/análise , Proteínas de Insetos/química , Brasil , Proteínas de Insetos/análise , Especificidade da Espécie , Espectroscopia de Infravermelho com Transformada de Fourier
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