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Amphibians have some of the most variable genome sizes among vertebrates. Genome size variation has been attributed to repetitive and noncoding DNA, including satellite repeats, transposable elements, introns, and nuclear insertions of viral and organelle DNA. In vertebrates, satellite DNAs have been widely described in mammals, but few molecular studies have been carried out in amphibians. Here, we provide a detailed characterization of a new family of satellite DNA, present in all 15 examined species of the family Bufonidae. Southern-blot analysis and PCR reveal that this satellite is formed by monomers of 807 bp, is organized in tandem arrays, and has an AT-content of 57.4%. Phylogenetic analyses show that most clades exhibit species-specific variances, indicating that this satellite DNA has evolved by concerted evolution. The homogenization/fixation process is heterogeneous in Bufonidae, where the genera Bufo and Bufotes do not show species-specific differences, while populations from Rhinella marina exhibit population-specific changes. Additionally, variants of this satellite DNA have been identified in Duttaphrynus melanostictus and R. marina, supporting the 'library hypothesis' (a set, 'library', of satellite DNAs is shared by a species group). Physical mapping in Bufo bufo, Bufo spinosus, Epidalea calamita and Bufotes viridis provides evidence that this repetitive DNA is not dispersed in the karyotype, but accumulated in pericentromeric regions of some chromosomal pairs. This location, together with its presence in the transcriptomes of bufonids, could indicate a role in centromere function or heterochromatin formation and maintenance. [ABSTRACT FROM AUTHOR]

Abstract: Amphibians epitomize the modern biodiversity crisis, and attract great attention from the scientific community since a complex puzzle of factors has influence on their disappearance. However, these factors are multiple and spatially variable, and declining in each locality is due to a particular combination of causes. This study shows a suitable statistical procedure to determine threats to amphibian species in medium size administrative areas. For our study case, ten biological and ecological variables feasible to affect the survival of 15 amphibian species were categorized and reduced through Principal Component Analysis. The principal components extracted were related to ecological plasticity, reproductive potential, and specificity of breeding habitats. Finally, the factor scores of species were joined in a presence-absence matrix that gives us information to identify where and why conservation management are requires. In summary, this methodology provides the necessary information to maximize benefits of conservation measures in small areas by identifying which ecological factors need management efforts and where should we focus them on. [Copyright &y& Elsevier]

The purpose of this study was to understand the differences in tolerance to ammonium nitrate in four Iberian amphibians. Results showed a negative effect on amphibian survival and larvae total length. Three different tolerance groups on amphibian survival were established. The two first groups showed a higher reduction, around 90% and between 70 and 80% after 96 h exposition at the maximum concentration tested (180 mg NHNO/L), while the third group showed no mortality in any concentration tested. In addition, a reduction in larvae total length was also detected for all four species, with Bufo bufo as the most sensitive species. [ABSTRACT FROM AUTHOR]

The article presents a study which analyzed the species of amphibians and reptiles in Morocco, particularly in the country's eastern region. It claims that the specimens used in the study were located through the use of a global positioning system (GPS). It cites that Morocco's topography is similar to that of Algeria and Tunisia. Among the species that were studied are the Bufo mauritanicus, pseudepidalea viridis, and Pelophylax saharicus. The other species include the Scutophis moilensis, Psammophis schokari and Spalerosophis dolichospilus.

We present two new types of noose for capturing herps, which allow adapting the size of the loop to the size of prey rapidly. We use a plastic ring to make the loop: the thread moves perfectly without any impediment or friction, and remains in good conditions for a longer time. The plastic ring can be made during fieldwork. Both new types of noose increase capture effectiveness, as it is possible to noose different types of preys with a simple and rapid adaptation of the loop. We have tested this methodology in different species of lacertids, some snakes under rocks, and also some amphibians. [ABSTRACT FROM AUTHOR]

Habitat fragmentation and alteration have been described as the major factors relating to the decline observed in several amphibian species. In Spain, these processes are mainly associated with the large agricultural land area, the widespread use of toxic substances, and the agricultural practices used. All these aggressions affect wetlands and their watersheds, which are essential aquatic systems for many amphibian species. In an effort to discover where conservation and specific action plans could be more necessary, this study relates the amphibian richness in 28 representative Mediterranean wetlands to their characteristics and the activities carried out on their watershed. The required information considers diverse wetland variables. Our results show that watershed habitat heterogeneity is significantly positively correlated with amphibian richness, while the percentage of the watershed area devoted to olive cultivation is negatively correlated with it. The results allow us to classify wetlands according to their importance for amphibian conservation. Our results also show that 80% of the studied wetlands need specific action plans. Especially, more sustainable cultivation methods are required considering drastic changes in current agricultural practices. Finally, our data provides a baseline to understand future alterations due to agricultural practices. [ABSTRACT FROM AUTHOR]