Aim: To test the importance of evolutionary and biogeographical processes in shaping the assembly of local frog communities in two adjacent regions (hereafter, coastal and inland regions) with different historical signatures. We asked two main questions: (1) why does the coastal region harbour more frog species than the inland region? and(2) how do these processes affect the spatial variation in taxonomic, phylogenetic and functional diversities within and across these regions? Location: southeastern Brazil.Taxon: Anurans. Methods:We generated time-calibrated phylogenies to estimate the relative timing of colonization, rates of speciation, extinction and dispersal between regions. We tested the phylogenetic signal in reproductive modes. These traits were also used to examine variation in functional composition across sites. We calculated metrics of phylogenetic community structure that capture the relationships near the root and tips of the tree. Finally, we tested the relationships between the spatial variation of multiple diversity dimensions and topographic complexity, Pleistocene and contemporary climate gradients for three spatial extents: (1) only coastal sites; (2) only inland sites; and (3) the two regions combined. Results:The structure of communities was related to the region in which they are located, with regional pool size being two times greater for the coastal than inland region. This pattern seems to reflect both a higher speciation rate and earlier colonization time in the coastal than in the inland region. Reproductive modes within frog genera were less variable than among families, indicating phylogenetic signal. This pattern influenced local community assembly within the inland region due to the absence of species with direct development, tadpoles in bromeliads or eggs and tadpoles in streams in this region. Main conclusions:Macroevolutionary dynamics, such as colonization time, differences in speciation rates and niche conservatism generate the disparity in species richness and assembly patterns of local communities between regions, but not within regions, in which local communities were more similar to each other.
The geographic distribution of Sphaenorhynchus lacteus comprises Amazon and Orinoco basins of South America, Guianas, eastern Brazil and Trinidad. Herein, we report for the first time the occurrence of Sphaenorhynchus lacteus and of the genus for the state of Piauí.
Parasites are an important component of the global biomass, having significant roles in several regulatory mechanisms in the ecosystem. Parasitism is one of the most common ecological interactions on the planet. Studies have shown that the helminth fauna of only 8% of amphibian species in Brazil have been studied, and this percentage is lower for the Odontophrynidae family, with only four of the 50 species kown to occur in Brazil having been investigated. Here, we present the helminth fauna of Proceratophrys ararype, an anuran endemic to the “Brejo de Altitude” Chapada do Araripe (Araripe Plateau), northeastern Brazil. The infection parameters analyzed were prevalence, mean intensity of infection and mean abundance of parasites. We used the Pearson’s linear correlation coefficient to check the correlations between the abundance of the parasites with the snout-vent length (SVL) of hosts. To verify the degree of aggregation of parasites in hosts, we used the dispersion index. Out of 40 specimens examined, 19 specimens were infected with at least one parasite. The overall prevalence was 47.5% with a mean infection intensity of 18.93 ± 10.77. The endoparasitic community associated with P. ararype consisted of six species of parasites, with Falcaustra mascula having the highest prevalence (25%). Most parasites had a uniform dispersion index in the hosts and their abundance was unrelated to host size. Here, we also present a compilation of all parasites associated with host species of the genus Proceratophrys from South America. Overall, we found 23 species of parasites associated with five host species (P. ararype, P. appendiculata, P. boiei, P. cristiceps, P. mantiqueira). Of these, two species of parasites (Oswaldocruzia mazzai and Strongyloides sp.) represent new records for the genus Proceratophrys. Our results demonstrate the lack of studies on amphibian helminth fauna and fill an important knowledge gap on the diversity of parasites of Proceratophrys ararype, an endemic frog from the Araripe Plateau, northeastern Brazil.
In this study, we describe the diet of Leptodactylus podicipinus in South Pantanal. We analysed the stomach content of 30 individuals collected in September 2017 in the Miranda sub-region, Mato Grosso do Sul. We identified 19 prey categories to Order level, out of which Coleoptera was the most representative group and the most important prey category, followed by Orthoptera and Hemiptera. We recorded a post-metamorphic individual of Rhinella schneideri in the diet of L. podicipinus, the first record of batracophagy for this species. Our results provide evidence for the opportunistic and generalist feeding behaviour of L. podicipinus.
The genus Physalaemus is widely distributed over South America, east of Andes. Physalaemus cicada belongs to the Physalaemus cuvieri group, is widely distributed over the Caatinga and is usually found in lentic and/or temporary water bodies. Herein, we extend its geographical distribution providing the first record of Physalaemus cicada for Piauí state, in the municipality of Picos.
The chytrid fungus Batrachochytrium dendrobatidis (Bd) has been linked to the declines of more than 500 amphibian species globally. In Brazil, Bd has been identified in several regions but predominantly in the Atlantic Forest. Data on the occurrence of this amphibian pathogen in northeastern Brazil are scarce, specifically from the Caatinga ecoregion, where there is only one study that reports Bd in the region. This study is the first to show a high prevalence of Bd in Caatinga's species and includes two new records of species infected by Bd: Rhinella granulosa and R. jimi. In addition, we discuss the possibility of amphibian with terrestrial habits serving as potential Bd reservoirs in semiarid climate regions.
Danish children find new bacteria One of the worlds' largest citizenscience experiments has led to the rapid discovery of ten new bacterial species in Denmark. About 25,000 schoolchildren aged 10-16 years found these Lactobacillus species after analysing some 11,000 plant samples from urban and rural ecosystems (see go.nature. com/2sq5muw). By comparison, Danish researchers find an average of just one new bacterial species per year. Lactobacillus is a beneficial group of bacteria that has been used for food preservation for thousands of years (M. Bernardeau et al. FEMS Microbiol. Rev. 30, 487-513; 2006). The study was spearheaded by the biotechnology company Novozymes near Copenhagen, and its updated biobank is now open to researchers around the world, offering fresh opportunities for industrial and drug development. Children are a large but untapped source of citizen scientists (see also Nature 562, 480-482; 2018). Moreover, they will form the next generation of scientists.
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