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We evaluate whether landscape variables surrounding urban remnant forest fragments influence ant diversity and its components in urban areas. The study was conducted in six riparian forest fragments in midwestern Minas Gerais State, Brazil, by sampling epigaeic and arboreal ants. Arboreal ants respond to fragmente isolation with changes in alpha, beta and gamma diversities. Isolation likely hinders dispersion and re-colonization such that the more isolated a fragment is, the less likely that new species arrive there. On other hand, epigaeic diversity did not show any response to variables of the surroundings or fragments, probably because natural periodic floods constitute a more severe disturbance for these ants. In addition, throughout the process of urbanization, anthropogenic improvements, such as paving, that prevent the natural percolation of water, increase the flooding of riparian soil. Arboreal ant species composition responds to percentage of urban area, fragment area and distance from the urban center, while epigaeic ants respond only to fragment area and percentage of urban area. We believe that even with the loss of species diversity and anthropogenic influences on fragments within urban centers, these areas are still important for species conservation. We also suggest the development of environmental protection projects for riparian áreas within urban centers, including investments in ecological corridors connecting fragments and public policies seeking to preserve these areas.

The performances of gas chromatography with mass spectrometry and of comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry are examined through the comparison of Daphnia magna metabolic profiles. Gas chromatography with mass spectrometry and comprehensive two-dimensional gas chromatography with mass spectrometry were used to compare the concentration changes of metabolites under saline conditions. In this regard, a chemometric strategy based on wavelet compression and multivariate curve resolution–alternating least squares is used to compare the performances of gas chromatography with mass spectrometry and comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry for the untargeted metabolic profiling of Daphnia magna in control and salinity-exposed samples. Examination of the results confirmed the outperformance of comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry over gas chromatography with mass spectrometry for the detection of metabolites in D. magna samples. The peak areas of multivariate curve resolution–alternating least squares resolved elution profiles in every sample analyzed by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry were arranged in a new data matrix that was then modeled by partial least squares discriminant analysis. The control and salt-exposed daphnids samples were discriminated and the most relevant metabolites were estimated using variable importance in projection and selectivity ratio values. Salinity de-regulated 18 metabolites from metabolic pathways involved in protein translation, transmembrane cell transport, carbon metabolism, secondary metabolism, glycolysis, and osmoregulation. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim ; Hadi Parastar would like to thank Sharif University of Technology (SUT) of Iran for financial support for a short sabbatical leave at IDAEA-CSIC. The research leading to these results received funding from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013) / ERC Grant Agreement no. 320737 ; Peer reviewed

Tryptophan hydroxylase (TRH) is the rate limiting enzyme in the serotonin synthesis. CRISPR-Cas9 technology was used to generate seven indel TRH mutants in Daphnia magna. Mono-allelic indel TRH-/+ clones showed normal levels of serotonin, measured by both immunohistochemistry and mass spectrometry (LC-MS/MS), whereas bi-allelic indel TRH-/- clones showed no detectable levels of serotonin. Life history and behavioral responses of TRH-/- clones showed the anti-phenotype of those exposed to selective serotonin reuptake inhibitors (SSRI). Mutants lacking serotonin grew less and hence reproduced latter, produced smaller clutches of smaller offspring and responded to a greater extent to light than wild type individuals. Mono-allelic indel TRH-/+ individuals showed the intermediate phenotype. The SSRI fluoxetine enhanced offspring production in all clones and decreased the response to light only in those clones having serotonin, thus indication that behavioral effects of this drug in D. magna are associated to serotonin. Results obtained with the TRH mutants are in line with reported ones in TRH knockouts of Caenorhabditis elegans, Drosophila and mice, indicating that there is one gene encoding TRH, which is the serotonin limiting enzyme in both the central and the periphery nervous system in Daphnia and that deprivation of serotonin increases anxiety-like behavior. © 2018 The Author(s). ; C.R. was supported by the Spanish PhD fellow BES-2012-053631. This work was supported by the Spanish Government: projects CTM2014-51985-R and CTM2017-83242-R ; Peer reviewed