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Myracrodruon urundeuva, popularly known as 'aroeira-do-sertão', a large tree, with a tall trunk. Belonging to the Anacardiaceae family, it occurs in the 'caatinga' and dry forests of Brazil, from Ceará to the states of Paraná and Mato Grosso do Sul. The present study aimed to analyse the whitening and antioxidant activities of the aqueous extract of the leaves of Myracrodruon urundeuva (AELMU). Inhibition of the tyrosinase enzyme, as well as its copper chelating capacity and antioxidant effect were evaluated. The AELMU (at 2000 µg/mL) showed excellent inhibitory action (83.76%) on tyrosinase by chelating the copper ion while kojic acid at the same concentration inhibited 97.81%. Moreover, the extract displayed important antioxidant activity (inhibited 76,46% of the 2,2-diphenyl-1-picrylhydrazyl radical - DPPH; 49,59% of thiobarbituric acid reactive substances and 51,07% of the hydroxyl radical). Thus, the extract under study is promising for use in cosmetics, given its multifactorial action. [ABSTRACT FROM AUTHOR]

In Brazil, the Caatinga ecoregion is the only biome that lies completely within the country, covering approximately 11% of the national territory. This biome exhibits a strong climatic seasonality that may affect the activity of its fauna. We aimed to assess the effects of seasonality on scorpion foraging activity in an area of hypoxerophytic Caatinga, located in the municipality of Caetés, Pernambuco. Scorpions were collected through active nocturnal searching using ultraviolet flashlights during the rainy (May, June, and July) and dry (September, October, and November) seasons in 2017. A total of 96 specimens were collected, belonging to the Buthidae and Bothriuridae families, comprising seven species, Ananteris sp., Tityus pusillus, T. stigmurus, T. neglectus, Jaguajir rochae, Bothriurus asper, and B. rochai. No differences in foraging activity (rainy season, n = 47; dry season, n = 49) were found between rainy and dry seasons. These findings indicate that the studied area has a high scorpion richness, emphasizing the importance of conserving the area, as these animals are sensitive to habitat changes. In addition, the lack of variation between seasons found in this work may reflect the ecotonal nature of hypoxerophytic Caatinga. [ABSTRACT FROM AUTHOR]

Introduction. The female-biased sex ratio is recurrently observed in bryophyte populations, although the sex ratio of spores is usually balanced. The results of several studies have suggested explanations for this observation, one of which is the shy male hypothesis. The shy male hypothesis predicts that the sex ratio of populations is balanced in the field, but due to a low or lack of sex expression of male plants, the populations present a female bias when the sex ratio is based on observations of sex-expressing plants. Methods. We tested the shy male hypothesis using samples of the moss Bryum argenteum collected from Brazilian seasonally dry tropical forests and the Brazilian Atlantic Forest. Field sex ratios were determined by classifying shoots as male, female, or non-sex-expressing. Non-sex-expressing shoots were further analysed for sex expression after culture regeneration. Results and discussion. Our results showed that populations of Bryum argenteum in the field had a low rate of sex expression, and that most of the shoots expressed were female. However, when shoots without sex expression were cultured, a greater number of male shoots were observed compared with in the field plants. Because more males appeared in the shoots cultured from non-sex-expressing field plants, our data for tropical B. argenteum tend to support the shy male hypothesis. Some genotypes from the wet forest were synoicous (i.e. had male and female gametangia in the same gametoecia), suggesting polyploidy. [ABSTRACT FROM AUTHOR]

During a survey of caves in a seasonally dry tropical forest area in northeastern Brazil, a new species of the genus Maxchernes was discovered and it is formally described here. The new species, named Maxchernes kapinawai sp. n., has affinities with M. iporangae, known from São Paulo State, Southeast Brazil. The new species, obtained from Pernambuco State, Northeastern Brazil, is characterized by the robust pedipalps, the measurements of pedipalpal femur, and patella different from other known Maxchernes species, in addition to the number of chelal teeth and males larger than females. This new species also represents the north-most record of Maxchernes genera so far. Ecological and conservation comments are included, as well as a map including reports known about the previous species. [ABSTRACT FROM AUTHOR]

The forests of South Africa and the neighbouring countries, including Lesotho, eSwatini, Namibia, Botswana, Zimbabwe, and Mozambique (south of the Zambezi River), were mapped and classified according to the global system of biomes. The new four-tier hierarchical biome system suggested in this paper includes zonobiome, global biome, continental biome (all recognised earlier), and regional biome – a novel biome category. The existing spatial coverages of the forests were revised and considerably improved, both in terms of forest-patch coverage and mapping precision. Southern Africa is home to three zonal forest types, namely Subtropical Forests (Zonobiome I), Tropical Dry Forest (TDF; Zonobiome II) and Afrotemperate Forests (Zonobiome X). These three biomes are characterised by unique bioclimatic envelopes. Five, two, and eight regional biomes, respectively, have been recognised within these zonal biomes. Recognition of the Zonobiome I and the global biome Tropical Dry Forests in southern Africa is novel and expands our knowledge of the biome structure of African biotic communities. The system of the azonal regional biomes is also new and comprehensively covers the variability of the azonal helobiomes (riparian woodlands and swamp forests), mangroves, and azonal coastal forests. In total, 11 azonal regional biomes have been recognised in the study area. The forest biomes in southern Africa were captured in our electronic map in the form of more than 60 000 polygons, covering 42 416 km2 (1.27% of the study area). No less than 83% of these forests occur in the territory of southern Mozambique. Abbreviations: for the abbreviation of the biome units, see Table 1; CE: centre of endemism; IOCB: Indian Ocean Coastal Belt; MBSA: the area of the Map of Biomes of Southern Africa; VegMap2006 and VegMap2018: Vegetation Map of South Africa, Lesotho and Swaziland (as released in respective years); for the meaning of the codes of the biome units see Table 1, and for the meaning of the abbreviations of climatic characteristics see Appendix S1 [ABSTRACT FROM AUTHOR]

Prediction of aboveground wood volume is one of most important stages when conducting a forest inventory and making forest management decisions. This is more difficult for native forest than for plantations given the high variability of the former (trees of different species and age groups). The objective of this work was to evaluate different strategies to estimate aboveground standing tree wood volume (v) using its diameter at breast height (DBH) and total height (h), comparing the use of form factors, volume equations fitted by ordinary least squares and mixed modelling, as well as the options from the literature. To achieve this, 351 trees were scaled during field campaigns, with 158 felled trees and 193 measured using Criterion equipment. The data collected from each scaled tree was: h, DBH, v and identification of the botanical species. We found that the best application of form factors occurred when the trees were divided by diameter classes. However, regression models, regardless of the fitting technique, presented better volume estimates than form factors. Mixed models, with either the species or diameter class as the random variable, provided the lowest errors when estimating tree volume. Thus, we recommend the use of mixed models as the best strategy to estimate volume of standing trees. The following equation can be used to estimate aboveground wood volume for trees from vegetation types similar to the ones of this study: ln(v) = −9.06013 + 1.91756 ln(DBH) + 0.69846 ln(h). [ABSTRACT FROM AUTHOR]

Tropical dry forests are diverse ecosystems that are globally threatened but are rarely protected. The main threat to this habitat is conversion for agricultural use. Here we evaluate the effects of environmental conversion, comparing patterns of beta diversity of butterflies in unconverted dry forest ecosystems (protected areas) and in agroecosystems (sugarcane and pasture). Butterflies were collected for 720 traps/day in 2018, using baited traps. Contrary to expectations, temporal beta diversity in sugarcane was higher than in forests. Nevertheless, the community in sugarcane contained mainly generalist species and its temporal dissimilarity was driven mainly by differences in species abundance. As expected, the spatial beta diversity between forest ecosystems and agroecosystems was high. Environmental conversion led to species loss, affecting mainly specialist species, which are more restricted to forest habitats, and resulted in a high degree of nesting of communities in agroecosystems. Our results emphasize the conservation value of protected natural areas and the importance of maintaining such areas as an essential strategy for conserving biodiversity. [ABSTRACT FROM AUTHOR]