Lignoids from the fruit of three Virola species

The fruits of Virola peruviana contain, besides i 1-phenyl-1-1-(2′,6′-dihydroxyphenyl)-undecan-1-one and the neolignan 2,3-dimethyl-1,4-diveratryl-n-butan-1-ol, 3,4-methylenedioxycinnamyl alcohol. In contrast, the fruits of V. flexuosa and V. multinervia both contain oxidative dimers of cinnamyl alcohols such as asarinin, cubebin, dihydrocubebin and sesamin. The former contains additionally fargesin and O-methylpiperitol, besides 7,4′-dimethoxyflavone, and the latter contains additionally hinokinin.     

Control of single-joint movements with a reversal.

We studied the kinematic and electromyographic (EMG) patterns during single-joint elbow flexion movements with a reversal and tested two hypotheses. First, that the amplitude of the second phase of the movement (M(2)) will be controlled by two different means, a drop in the second flexor burst for a small M(2) and an increase in the integral of the extensor burst for larger M(2). Second, based on the muscle stretch-shortening cycle (SSC), that movements reversing without a delay will show a larger extensor burst, as compared to movements that reverse after a delay. Changes in EMG patterns with M(2) amplitude supported the first hypothesis and could be interpreted within the framework of the equilibrium-point hypothesis. The observations also corroborate a hypothesis that discrete movements represent outcomes of an oscillatory control process stopped at a particular phase. In Experiment-2, even the shortest delay at the target led to a significantly larger extensor burst. However, there were no differences in the peak velocity of M2 with and without the delay. These observations do not support a major role of stretch reflexes in the SSC effects during such movements. However, they are compatible with the idea of peripheral factors, such as peripheral muscle and tendon elasticity, playing a major potentiating role in the SSC.     

Genetic diversity of Saccharina latissima (Phaeophyceae) along a salinity gradient in the North Sea–Baltic Sea transition zone

The North Sea–Baltic Sea transition zone constitutes a boundary area for the kelp species Saccharina latissima due to a strong salinity gradient operating in the area. Furthermore, the existence of S. latissima there, along Danish waters, is fairly patchy as hard bottom is scarce. In this study, patterns of genetic diversity of S. latissima populations were evaluated along the salinity gradient area of Danish waters (here designated brackish) and were compared to reference sites (here designated marine) outside the gradient area, using microsatellite markers. The results showed that the S. latissima populations were structured into two clusters corresponding to brackish versus marine sites, and that gene flow was reduced both between clusters and between populations within clusters. In addition, results provided empirical evidence that marginal populations of S. latissima in the salinity gradient area exhibited a distinct genetic structure when compared to marine ones. Brackish populations were less diverse, more related, and showed increased differentiation over distance compared to marine populations. The isolation of the brackish S. latissima populations within the salinity gradient area of Danish waters in conjunction with their general low genetic diversity makes these populations vulnerable to ongoing environmental and climate change, predicted to result in declining salinity in the Baltic Sea area that may alter the future distribution and performance of S. latissima in the area.     

Importance of temporal variability at different spatial scales for diversity of floodplain aquatic communities

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Molecular systematics of teioid lizards (Teioidea/Gymnophthalmoidea: Squamata) based on the analysis of 48 loci under tree‐alignment and similarity‐alignment

We infer phylogenetic relationships within Teioidea, a superfamily of Nearctic and Neotropical lizards, using nucleotide sequences. Phylogenetic analyses relied on parsimony under tree‐alignment and similarity‐alignment, with length variation (i.e. gaps) treated as evidence and as absence of evidence, and maximum‐likelihood under similarity‐alignment with gaps as absence of evidence. All analyses produced almost completely resolved trees despite 86% of missing data. Tree‐alignment produced the shortest trees, the strict consensus of which is more similar to the maximum‐likelihood tree than to any of the other parsimony trees, in terms of both number of clades shared, parsimony cost and likelihood scores. Comparisons of tree costs suggest that the pattern of indels inferred by similarity‐alignment drove parsimony analyses on similarity‐aligned sequences away from more optimal solutions. All analyses agree in a majority of clades, although they differ from each other in unique ways, suggesting that neither the criterion of optimality, alignment nor treatment of indels alone can explain all differences. Parsimony rejects the monophyly of Gymnophthalmidae due to the position of Alopoglossinae relative to Teiidae, whereas support of Gymnophthalmidae by maximum‐likelihood was low. We address various nomenclatural issues, including Gymnophthalmidae Fitzinger, 1826 being an older name than Teiidae Gray, 1827. We recognize three families in the arrangement Alopoglossidae + (Teiidae + Gymnophthalmidae). Within Gymnophthalmidae we recognize Cercosaurinae, Gymnophthalminae, Rhachisaurinae and Riolaminae in the relationship Cercosaurinae + (Rhachisaurinae + (Riolaminae + Gymnophthalminae)). Cercosaurinae is composed of three tribes—Bachiini, Cercosaurini and Ecpleopodini—and Gymnophthalminae is composed of three—Gymnophthalmini, Heterodactylini and Iphisini. Within Teiidae we retain the currently recognized three subfamilies in the arrangement: Callopistinae + (Tupinambinae + Teiinae). We also propose several genus‐level changes to restore the monophyly of taxa.     

Caatinga Ethnobotany: Anthropogenic Landscape Modification and Useful Species in Brazil’s Semi-Arid Northeast

Caatinga Ethnobotany: Anthropogenic Landscape Modification and Useful Species in Brazil’s Semi-Arid Northeast This study explores the contribution of anthropogenic landscapes in providing useful botanical resources to a Caatinga community in Pernambuco, Brazil. Ethnobotanical data were collected through semi-structured interviews using the checklist-interview method and by means of a “field herbarium” of the most abundant species in the anthropogenic zones. We recorded 119 species distributed in 36 families, of which 79 were found to be useful. Forage was the most prominent use category, containing 84% of the citations, followed by medicinals (36.70%), foods (10.12%), and wood (8.86%). Herbaceous species predominated (63.29%), followed by shrubs (3.79%), sub-shrubs (21.51%), trees (8.86%), and creepers (2.53%). Trees exhibited a greater number of uses than other life-forms (p < 0.05). Significant differences in richness were found, with the highest richness of species (χ2 = 60.28, p < 0.05), genera (χ2 = 49.03, p < 0.05), and families (χ2 = 20.16, p < 0.05) appearing in the rainy season. We concluded that fodder use was the most important category in our anthropogenic research areas, accounting for a higher number of species, genera, and families. The next most important categories were medicinal, timber, and food plants, respectively.     

Genetic structure and management of the Neotropical migratory fish Megaleporinus obtusidens on a highly impacted river basin

Habitat fragmentation caused by hydroelectric dams has depleted fish populations worldwide. Restocking actions are usually adopted to recover those populations, but hatchery management protocols rarely guarantee the maintenance of genetic diversity and a balanced contribution among captive breeders each generation. Here, a set of 10 microsatellite markers was used to assess the genetic diversity (average allelic richness A_R?=?10.87 and expected heterozygosity H_E?=?0.742, respectively) and structuring of Megaleporinus obtusidens, a migratory freshwater fish inhabiting over 2500 km of the São Francisco River in Brazil. Three main genetic clusters were identified in this species across the river basin that could be related to the sharply different climatic and hydrologic regimes from the Upper to the Lower course. A significant reduction (> 50%) in genetic diversity was observed in the broodstock when compared to their wild conspecifics, especially in the allelic richness. The information here presented will aid for management of genetic resources of this species in the São Francisco River taking as reference the genetic clusters identified. Furthermore, the results indicated that restocking is not necessary unless signals of population depletion occurs and, if so, hatchery reproductive protocols should rely on artificial fertilization rather than mass spawning.