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1.
Sci Rep ; 12(1): 11656, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35804053

RESUMO

The neotropical region ranks third in the number of termites and includes five different families. Of these, Termitidae is the most diverse and includes the species Nasutitermes ephratae, which is widespread in the neotropics. To date, only one study has been published about phylogeography in neotropical termites (N. corniger). Here, we explored the population genetic patterns of N. ephratae and also evaluated the phylogeographical processes involved in the evolutionary history of the species. We used the mitochondrial genes 16S rRNA and COII as molecular markers: these were sequenced for 128 samples of N. ephratae. We estimated the genetic diversity and divergence time as well as the demography and genetic structure. We also performed an ancestral area reconstruction and a haplotype network. The results showed high genetic variability, recent demographic expansion, and strong genetic structure. A dispersal route for the species, that occurred in both directions between South and Central America, was inferred. The results emphasize a temporary separation between the South and Central America populations that affected the origin of the current Central America populations. These populations were formed from different phylogeographic histories.


Assuntos
Isópteros , Animais , Evolução Biológica , DNA Mitocondrial/genética , Variação Genética , Genética Populacional , Humanos , Isópteros/genética , Filogenia , Filogeografia , RNA Ribossômico 16S/genética
2.
Ecol Evol ; 11(2): 700-713, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33520159

RESUMO

Habitat loss is the main threat to biodiversity conservation worldwide. Some species may be particularly susceptible to the effects of fragmentation and the isolation of populations. The impacts of human activity on wild animal populations may be understood through relationships between individual genetic data and spatial landscape variables, particularly when considering local population dynamics influenced by fragmented habitats. Thus, the objective of this study was to analyze the population structure and genetic diversity of the giant anteater (Myrmecophaga tridactyla) using an individual sampling scheme (ISS) on a regional geographic scale. Data were collected from 41 specimens from twenty different locations in São Paulo State, Brazil, and six polymorphic microsatellite loci were genotyped. Our results indicate that barriers to gene flow exist and have segregated individuals of the farther away areas into two spatially structured clusters. The populations were also found to have high genetic diversity. The experimental sampling approach used herein enabled an analysis of the population dynamics of the giant anteater on a regional scale, as well as the identification of priority populations for genetic resource conservation for this species. The results reflect the need for adequate management plans. The efficacy of the sampling scheme may vary based on the study model used, but we argue that the use of an ISS combined with suitable molecular markers and statistical methods may serve as an important tool for initial analyses of threatened or vulnerable species, particularly in anthropized regions where populations are small or hard to characterize.

3.
Environ Entomol ; 49(3): 765-775, 2020 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-32198507

RESUMO

The species of the genus Ceraeochrysa, known as green lacewings or trash-carriers, are widely distributed along the Americas and its islands. In Brazil, 28 species are found, including Ceraeochrysa cincta (Schneider), Ceraeochrysa claveri (Navás), and Ceraeochrysa cubana (Hagen). These species are recorded on many crops, where they are often used for biological control. For this use, knowledge of the genetic features of the species is extremely important because they are associated to the species' ability to withstand different conditions in new environments, such as variations of temperature and presence of pathogens. However, little is known about the genetic features of Ceraeochrysa species. Here, we analyze and compare the distribution of the genetic variability of C. cincta, C. claveri, and C. cubana in agroecosystem populations of southeast Brazil. We found a high genetic diversity in each of the three species, and no strong genetic structure was detected, such that genetic diversity is broadly shared among the crops and localities analyzed. We can conclude that there was a high gene flow among the sampled Ceraeochrysa populations (natural or driven by anthropic action) since the exchange of seedlings among crops can lead to the distribution of the specimens.


Assuntos
Produtos Agrícolas , Insetos , Animais , Brasil
4.
Rev. bras. entomol ; 53(4): 499-503, dez. 2009. ilus, graf, tab
Artigo em Português | LILACS | ID: lil-543408

RESUMO

As espécies do gênero Chrysoperla que ocorrem no Brasil -C. externa (Hagen, 1861), C. defreitasi (Brooks, 1994), C. raimundoi (Freitas & Penny, 2001) e C. genanigra (Freitas, 2003)-, que apresentam as principais diferenças nas genitálias, foram estudadas morfometricamente através das distâncias entre pontos da cabeça (oito medidas lineares) a fim de melhor identificá-las. Os resultados, analisados através da estatística multivariada, mostraram que é possível se identificarem medidas que as distinguem individualmente, muito embora algumas espécies sejam mais distinguíves através da morfometria. A análise canônica mostrou que três das quatro espécies, C. raimundoi; C. genanigra e C. externa, não apresentaram grandes sobreposições entre si, sendo possível sua discriminação dentro do grupo, somente C. defreitasi apresentou uma baixa resolução de acordo com esta análise, ficando sobreposta com C. externa e C. genanigra, no entanto, ela é totalmente discriminada de C. raimundoi. As medidas que mais contribuíram para a diferenciação estão relacionadas ao tamanho da cabeça e em especial ao comprimento do labro, na extremidade da cabeça, até o nível dos olhos e antena.


The species C. externa, C. defreitasi, C. raimundoi and C. genanigra (Neuroptera, Chrysopidae) have great differences in the genitalia. These species were studied morphometrically by the distances between points of the head (eight linear measurements) to better identify them. The results, analyzed by multivariate statistics, showed that it is possible to identify measures that distinguish the individual, although some species are more distinguishable by morphometry. The canonical analysis showed that three of the four species, C. raimundoi, C. genanigra and C. externa, showed no major overlap between them, and their possible discrimination within the group, only C. defreitasi presented a low resolution according to this analysis, being overlapped with C. externa and C. genanigra, however, it is totally broken in C. raimundoi. The measures that contributed most to differentiation are related to the size of the head and especially the length of wrasse on the edge of the head, until the level of the eyes and antenna.

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