RESUMO
Nanorana yunnanensis has been reported in Thailand for many years; however, no specimens have been verifiably described. To verify the identity of this species in Thailand, we observed Thai specimens formerly assigned to the species N. bourreti and N. yunnanensis. The 12S rRNA, 16S rRNA, and ND2 mitochondrial genes were used to clarify the taxonomic statuses of the Thai specimens. The results showed that our specimens formed a clade with N. yunnanensis, containing specimens from southern Yunnan and Vietnam. The respective mean sequence divergences of the 12S and 16S rRNA genes between populations from Thailand versus China were 0.59% and 1.09%, for populations from Thailand versus Vietnam were 0.57% and 0.61%, and for populations from China versus Vietnam were 0.59% and 1.09%. We provide descriptions of the tadpole and adult specimens of N. yunnanensis from Thailand.
Assuntos
Anuros , Animais , Anuros/genética , Filogenia , RNA Ribossômico 16S/genética , Tailândia , Larva/genética , ChinaRESUMO
Diospyrosdussaudii is a poorly known species and previous descriptions lacked details about its female flowers and fruits. The species had not been recorded since type collections were made in 1913. As a result of our Diospyros research in Thailand, new specimens and data are now available for this species. In this study, we provide an updated morphological description, illustrations, lectotypification and a distribution map. The species was previously reported to be endemic to Laos; as such, the occurrences in Thailand greatly expand the distribution of the species. In addition, we analysed the phylogenetic relationships between D.dussaudii and other Diospyros species from Southeast Asia and other regions, using DNA sequence data from eight plastid regions. Our phylogenetic analyses indicate that D.dussaudii is closely related to D.castanea, D.dasyphylla and D.insidiosa. Their taxonomic affinities are discussed.
RESUMO
Captive breeding programs are crucial to ensure the survival of endangered species and ultimately to reintroduce individuals into the wild. However, captive-bred populations can also deteriorate due to inbreeding depression and reduction of genetic variability. We genotyped a captive population of 82 individuals of the endangered Hume's pheasant (Syrmaticus humiae, Hume 1881) at the Doi Tung Wildlife Breeding Center to assess the genetic consequences associated with captive breeding. Analysis of microsatellite loci and mitochondrial D-loop sequences reveal significantly reduced genetic differentiation and a shallow population structure. Despite the low genetic variability, no bottleneck was observed but 12 microsatellite loci were informative in reflecting probable inbreeding. These findings provide a valuable source of knowledge to maximize genetic variability and enhance the success of future conservation plans for captive and wild populations of Hume's pheasant.
Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Variação Genética/genética , Codorniz/genética , Animais , Animais Selvagens , Cruzamento , Genótipo , Haplótipos/genética , Endogamia , Repetições de Microssatélites/genéticaRESUMO
The complete mitochondrial genome (mitogenome) of Tropidophorus hangnam was sequenced from its paratype (GenBank accession no. MN977920). It was 16,777 bp in length with a base composition of 31.99% A, 29.49% C, 14.34% G, and 24.18% T, and a GC content of 43.83%. The genome includes 13 protein-coding genes (PCGs), 22 transfer RNA genes, 2 ribosomal RNA genes, and a control region (D loop). Most T. hangnam genes are located on the H strand, except for the ND6 gene and eight tRNA genes, which are located on the L strand. Phylogenetic analyses based on 13 PCGs indicated that T. hangnam is sister to the clade composed of the genera Scincella and Sphenomorphus. The newly sequenced T. hangnam mitogenome will provide basic data for further studies on the genetic diversity and molecular phylogenetic relationships of the genus Tropidophorus.
RESUMO
The complete mitochondrial genome (mitogenome) of the rare Fea's muntjac (Muntiacus feae) was sequenced (GenBank accession nos. MG857662-MG857664). The mitogenome was found to be 16,355 bp in length with base compositions of 33.16% A, 24.59% C, 13.46% G, and 28.78% T and a GC content of 38.06%. The genome is comprised of 13 protein-coding genes (PCGs), 22 transfer RNA genes, 2 ribosomal RNA genes, and a control region (D-loop). Phylogenetic analysis revealed that Fea's muntjac is more closely related to Black muntjac (M. cronifrons) than to Red muntjac (M. muntjak). These data will be useful for further studies on the genetic diversity and molecular phylogenetic relationship of the genus Muntiacus.
RESUMO
Two tropical plant species, Lasianthus pilosus and Lasianthus stipularis are used in traditional medicine but there have been no published studies of the extracts of these plants against bacteria. In this study, we aimed to determine the antimicrobial activities of the above two plants against two gram-positive and seven gram-negative bacterial strains to determine the potential of these two plant species for possible antimicrobial drug development. The antibacterial activities of the lipophilic extracts of these plants were evaluated by disk diffusion and broth microdilution methods. The zone diameters and minimum inhibitory concentrations (MIC) for these plant extracts exhibited their highest antibacterial activity against Pseudomonas aeruginosa, followed by Staphylococcus aureus and Acinetobacter baumannii, respectively. The MIC of these extracts against P. aeruginosa (ATCC 37166 and ATCC 27853) varied from 50 to 200 µg/ml. Thin layer chromatography and detection using different specific reagents revealed the presence of terpenoids, phenolic compounds and iridoid. Cell lysis due to the effect of the lipophilic extracts of these tested plants was demonstrated using scanning electron microscopy. In conclusion, the bioactive compounds of these plants should be studied further to develop potential antimicrobial agents.
Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rubiaceae/química , Extratos Vegetais/química , Rubiaceae/classificação , Especificidade da EspécieRESUMO
BACKGROUND: Radiation in some plant groups has occurred on islands and due to the characteristic rapid pace of phenotypic evolution, standard molecular markers often provide insufficient variation for phylogenetic reconstruction. To resolve relationships within a clade of 21 closely related New Caledonian Diospyros species and evaluate species boundaries we analysed genome-wide DNA variation via amplified fragment length polymorphisms (AFLP). RESULTS: A neighbour-joining (NJ) dendrogram based on Dice distances shows all species except D. minimifolia, D. parviflora and D. vieillardii to form unique clusters of genetically similar accessions. However, there was little variation between these species clusters, resulting in unresolved species relationships and a star-like general NJ topology. Correspondingly, analyses of molecular variance showed more variation within species than between them. A Bayesian analysis with BEAST produced a similar result. Another Bayesian method, this time a clustering method, Structure, demonstrated the presence of two groups, highly congruent with those observed in a principal coordinate analysis (PCO). Molecular divergence between the two groups is low and does not correspond to any hypothesised taxonomic, ecological or geographical patterns. CONCLUSIONS: We hypothesise that such a pattern could have been produced by rapid and complex evolution involving a widespread progenitor for which an initial split into two groups was followed by subsequent fragmentation into many diverging populations, which was followed by range expansion of then divergent entities. Overall, this process resulted in an opportunistic pattern of phenotypic diversification. The time since divergence was probably insufficient for some species to become genetically well-differentiated, resulting in progenitor/derivative relationships being exhibited in a few cases. In other cases, our analyses may have revealed evidence for the existence of cryptic species, for which more study of morphology and ecology are now required.
Assuntos
Diospyros/classificação , Diospyros/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Teorema de Bayes , Evolução Biológica , Análise por Conglomerados , DNA de Plantas/genética , Ecologia , Nova Caledônia , Filogeografia , Polimorfismo GenéticoRESUMO
To clarify phylogenetic relationships among New Caledonian species of Diospyros, sequences of four plastid markers (atpB, rbcL, trnK-matK and trnS-trnG) and two low-copy nuclear markers (ncpGS and PHYA) were analysed. New Caledonian Diospyros species fall into three clades, two of which have only a few members (1 or 5 species); the third has 21 closely related species for which relationships among species have been mostly unresolved in a previous study. Although species of the third group (NC clade III) are morphologically distinct and largely occupy different habitats, they exhibit little molecular variability. Diospyros vieillardii is sister to the rest of the NC clade III, followed by D. umbrosa and D. flavocarpa, which are sister to the rest of this clade. Species from coastal habitats of western Grande Terre (D. cherrieri and D. veillonii) and some found on coralline substrates (D. calciphila and D. inexplorata) form two well-supported subgroups. The species of NC clade III have significantly larger genomes than found in diploid species of Diospyros from other parts of the world, but they all appear to be diploids. By applying a molecular clock, we infer that the ancestor of the NC clade III arrived in New Caledonia around 9 million years ago. The oldest species are around 7 million years old and the youngest ones probably much less than 1 million years.
Assuntos
Diospyros/classificação , Evolução Molecular , Genoma de Planta , Filogenia , Teorema de Bayes , Núcleo Celular/genética , DNA de Cloroplastos/genética , DNA de Plantas/genética , Diospyros/genética , Diploide , Ecossistema , Marcadores Genéticos , Modelos Genéticos , Nova Caledônia , Análise de Sequência de DNARESUMO
We aimed to clarify phylogenetic relationships within the pantropical genus Diospyros (Ebenaceae sensulato), and ascertain biogeographical patterns in the New Caledonian endemic species. We used DNA sequences from eight plastid regions (rbcL, atpB, matK, ndhF, trnK intron, trnL intron, trnL-trnF spacer, and trnS-trnG spacer) and included 149 accessions representing 119 Diospyros species in our analysis. Results from this study confirmed the monophyly of Diospyros with good support and provided a clearer picture of the relationships within the genus than in previous studies. Evidence from phylogenetic analyses suggests that Diospyros colonized New Caledonia multiple times. The four lineages of Diospyros in New Caledonia also differ in their degree of diversification. The molecular data indicate that one lineage is paleoendemic and derived from an ancient Australian species. The other three lineages are more closely related to several Southeast Asian species; two of them are neoendemics, and one has radiated rapidly and recently.
Assuntos
Diospyros/genética , Evolução Molecular , Filogenia , Plastídeos/genética , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Diospyros/classificação , Genes de Plantas , Geografia , Dados de Sequência Molecular , Nova Caledônia , Alinhamento de Sequência , Análise de Sequência de DNARESUMO
Phylogenetic relationships of the pantropical family Ebenaceae s.l. were investigated using plastid DNA sequence data from six regions: atpB, matK, ndhF, trnK intron, trnL intron, and trnL-trnF spacer. Sampling included representatives of all currently recognized genera of Ebenaceae, Diospyros, Euclea, and Lissocarpa, and nearly all taxa that were previously recognized at the generic level, e.g., Cargillia, Gunisanthus, Maba, Macreightia, Royena, and Tetraclis. Our results strongly support monophyly of Ebenaceae s.l. and demonstrate that the previous infrafamilar classifications of the family do not circumscribe monophyletic groups. A new infrafamilial classification based on a phylogenetic approach is proposed here and consists of two subfamilies, Lissocarpoideae and Ebenoideae, and four genera, Lissocarpa, Euclea, Royena, and Diospyros. Relationships and potential synapomorphic characters are discussed and summarized. This study supports a western Gondwanan origin of family and indicates that both vicariant and long-distance dispersal events played an important role in attaining current distributions.