Molecular phylogeny of Moenkhausia (Characidae) inferred from mitochondrial and nuclear DNA evidence

Moenkhausia is one of the most speciose genera in Characidae, currently composed of 75 nominal species of small fishes distributed across South American hydrographic basins, primarily the Amazon and Guyanas. Despite the large number of described species, studies involving a substantial number of its species designed to better understand their relationships and putative monophyly are still lacking. In this study, we analysed a large number of species of Moenkhausia to test the monophyly of the genus based on the phylogenetic analysis of DNA sequences of two mitochondrial and three nuclear genes. The in-group included 29 species of Moenkhausia, and the out-group was composed of representatives of Characidae and other members of Characiformes. All species of Moenkhausia belong to the same clade (Clade C); however, they appear distributed in five monophyletic groups along with other different genera, which means that Moenkhausia is polyphyletic and indicates the necessity of an extensive revision of the group. © 2013 Blackwell Verlag GmbH.

Initial description of the phylogeography, population structure and genetic diversity of Atlantic spotted dolphins from Brazil and the Caribbean, inferred from analyses of mitochondrial and nuclear DNA

We provide initial information regarding the population structure and genetic diversity of Stenella frontalis from the Caribbean and southeastern Brazil from analyses of mitochondrial control region sequences and sequences from the first intron of the α-lactalbumin gene. Comparisons with previously described S. frontalis sequences showed a high number of haplotypes shared between populations throughout their distribution range. High diversity was found for southeastern Brazil and Caribbean samples, and population structure analyses indicate significant differentiation among population units at the FST level, but not at the ΦST level. Significant differentiation at the FST level was found between the Caribbean population unit and all other populations units. These results suggest historical or present connectivity between the Azores and Madeira and the southeastern Brazil groups and population differentiation between the Caribbean and southeastern Brazil, supporting the notion of two separate stocks in the waters around the Atlantic coast of South America. © 2013 Elsevier Ltd.

Composition and interrelationships of a large Neotropical freshwater fish group, the subfamily Cheirodontinae (Characiformes: Characidae): A case study based on mitochondrial and nuclear DNA sequences

•Relationships of Cheirodontinae based on a broad taxonomic sample.•Results reject the monophyly of Cheirodontinae as previously conceived.•Exclusion of Amazonspinther and Spintherobolus from the subfamily Cheirodontinae.•The removal of Leptagoniates pi of the genus Leptagoniates and inclusion in Cheirodontinae.•Division of Cheirodontinae in three newly defined monophyletic tribes. Characidae is the most species-rich family of freshwater fishes in the order Characiformes, with more than 1000 valid species that correspond to approximately 55% of the order. Few hypotheses about the composition and internal relationships within this family are available and most fail to reach an agreement. Among Characidae, Cheirodontinae is an emblematic group that includes 18 genera (1 fossil) and approximately 60 described species distributed throughout the Neotropical region. The taxonomic and systematic history of Cheirodontinae is complex, and only two hypotheses about the internal relationships in this subfamily have been reported to date. In the present study, we test the composition and relationships of fishes assigned to Cheirodontinae based on a broad taxonomic sample that also includes some characid incertae sedis taxa that were previously considered to be part of Cheirodontinae. We present phylogenetic analyses of a large molecular dataset of mitochondrial and nuclear DNA sequences. Our results reject the monophyly of Cheirodontinae as previously conceived, as well as the tribes Cheirodontini and Compsurini, and the genera Cheirodon, Compsura, Leptagoniates, Macropsobrycon, Odontostilbe, and Serrapinnus. On the basis of these results we propose: (1) the exclusion of Amazonspinther and Spintherobolus from the subfamily Cheirodontinae since they are the sister-group of all remaining Characidae; (2) the removal of Macropsobrycon xinguensis of the genus Macropsobrycon; (3) the removal of Leptagoniates pi of the genus Leptagoniates; (4) the inclusion of Leptagoniates pi in the subfamily Cheirodontinae; (5) the removal of Cheirodon stenodon of the genus Cheirodon and its inclusion in the subfamily Cheirodontinae under a new genus name; (6) the need to revise the polyphyletic genera Compsura, Odontostilbe, and Serrapinnus; and (7) the division of Cheirodontinae in three newly defined monophyletic tribes: Cheirodontini, Compsurini, and Pseudocheirodontini. Our results suggest that our knowledge about the largest Neotropical fish family, Characidae, still is incipient. © 2013 Elsevier Inc..

Systematics of spiny-backed treefrogs (Hylidae: Osteocephalus): An Amazonian puzzle

Spiny-backed tree frogs of the genus Osteocephalus are conspicuous components of the tropical wet forests of the Amazon and the Guiana Shield. Here, we revise the phylogenetic relationships of Osteocephalus and its sister group Tepuihyla, using up to 6134 bp of DNA sequences of nine mitochondrial and one nuclear gene for 338 specimens from eight countries and 218 localities, representing 89% of the 28 currently recognized nominal species. Our phylogenetic analyses reveal (i) the paraphyly of Osteocephalus with respect to Tepuihyla, (ii) the placement of 'Hyla' warreni as sister to Tepuihyla, (iii) the non-monophyly of several currently recognized species within Osteocephalus and (iv) the presence of low (<1%) and overlapping genetic distances among phenotypically well-characterized nominal species (e.g. O. taurinus and O. oophagus) for the 16S gene fragment used in amphibian DNA barcoding. We propose a new taxonomy, securing the monophyly of Osteocephalus and Tepuihyla by rearranging and redefining the content of both genera and also erect a new genus for the sister group of Osteocephalus. The colouration of newly metamorphosed individuals is proposed as a morphological synapomorphy for Osteocephalus. We recognize and define five monophyletic species groups within Osteocephalus, synonymize three species of Osteocephalus (O. germani, O. phasmatus and O. vilmae) and three species of Tepuihyla (T. celsae, T. galani and T. talbergae) and reallocate three species (Hyla helenae to Osteocephalus, O. exophthalmus to Tepuihyla and O. pearsoni to Dryaderces gen. n.). Furthermore, we flag nine putative new species (an increase to 138% of the current diversity). We conclude that species numbers are largely underestimated, with most hidden diversity centred on widespread and polymorphic nominal species. The evolutionary origin of breeding strategies within Osteocephalus is discussed in the light of this new phylogenetic hypothesis, and a novel type of amplexus (gular amplexus) is described. © 2013 The Norwegian Academy of Science and Letters.

Evaluation of the psychrotrophic specific signatures for cspA gene and 16S rDNA on the phenotype of Bacillus cereus sensu strictu

This study characterised the psychrotrophic genotypes and phenotypes behaviour of 63 strains of Bacillus cereus sensu stricto isolated from dairy products. The presence of the cspA gene signature and the 16S rDNA mesophilic and/or psychrotrophic specific signatures was evaluated. Among the strains, 25 (39.7%) had the cspA gene signature, 38 (60.3%) had both mesophilic and psychrotrophic 16S rDNA signatures, 24 (38.1%) had only mesophilic and one exhibited only psychrotrophic. No strain grew at 7 °C. The results indicate that the presence of psychrotrophic signatures for cspA gene or the 16S rDNA did not ensure a psychrotrophic behaviour on a B. cereus phenotype. © 2013 Society of Dairy Technology.

Cross-mating experiments detect reproductive compatibility between Triatoma sherlocki and other members of the Triatoma brasiliensis species complex

Phylogenetic approaches based on mitochondrial DNA variation (fragments of Cyt B and 16S ribosomal RNA) have revealed Triatoma sherlocki as the most recent species addition to the Triatoma brasiliensis species complex; a monophyletic group which includes T. brasiliensis, Triatoma melanica, and Triatoma juazeirensis. T. sherlocki is the most differentiated among all species of this complex: it is unable to fly, possesses longer legs than the other members, and has reddish tonality in some parts of its exochorion. We question whether these species are reproductively compatible because of this pronounced morphological differentiation, and therefore, we present a series of cross breeding experiments that test compatibility between T. sherlocki and other members of the T. brasiliensis complex. We extended our analyses to include crosses between T. sherlocki and Triatoma lenti, because the latter has been suggested as a possible member of this complex. T. sherlocki male. ×. T. lenti female pairs failed to produce hybrids. All other crosses of T. sherlocki and members of T. brasiliensis species complex, as well as backcrosses, produced viable offspring through the third generation. This study stresses the importance of searching for the features that may isolate members of the T. brasiliensis species complex. © 2013 Elsevier B.V.

Filogeografia de Thoropa grupo miliaris (Anura: Cycloramphidae)

Pós-graduação em Biologia Animal - IBILCE

Análises moleculares e da presença de endobactérias de Camponotus textor Forel, 1899 (Hymenoptera, Formicidae)

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC

Análise filogenética de linhagens de Xylella fastidiosa de diferentes hospedeiros baseada na sequencia da região intergênica 16S-23S rDNA

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC

Filogenia molecular de cianobactérias baseada em sequências do 16S-23S-ITS rDNA e PC-IGS: investigação de transferência lateral do PC

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estrutura cromossômica e caracterização cariotípica no complexo de espécies Synbranchus marmoratus (Teleostei, Synbranchiformes, Synbranchidae)

Pós-graduação em Ciências Biológicas (Genética) - IBB

Caracterização molecular da estrutura genética de populações e espécies camarões palemonídeos Macrobrachium do gênero Macrobrachium

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Identificação de estirpes de rizóbios por seqüenciamento parcial dos genes 16S rDNA e nifH

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Identificação de comunidades bacterianas de solo por seqüenciamento do gene 16S rRNA

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relação filogenètica entre sete espécies de Triatominae (Hemiptera, Reduviidae) da região Centro-Oeste do Brasil baseada no sequenciamento de genes mitocondriais

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)