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Context. Species of the tropical frog Family Hylodidae tend to be restricted to streams and, hence, have a small occupancy area. Hylodes fredi (Canedo and Pombal 2007), a diurnal stream-dwelling species endemic to the Atlantic Forest in Ilha Grande, south-eastern Brazil, is one such species. Because of scarce population studies, it is also categorised as Data Deficient (DD) in the IUCN Red List. Previous studies on the habitat use by this species did not account for imperfect detection, which could have led to biased results. Aims. We aimed to systematically describe the microhabitats occupied by H. fredi, by generating a fine-scale occupancy model while accounting for imperfect detection. Methods. We sampled six streams where the species is known to occur. Perpendicular transects were established in each stream and further subdivided into 10 sampling plots. Single-species and single-season occupancy models were created with the UNMARKED R package, and model selection was performed on the basis of the Akaike information criterion. Key results. We observed the species in 70 of the 275 sampled sites, which resulted in a naïve occupancy of 0.28 and detectability of 0.25. The best models suggest that H. fredi occupancy increases positively with rock cover and inversely with leaf-litter cover. Detectability reduced with an increase in leaf litter cover and varied with the airtemperature. Conclusions. We conclude that H. fredi occupancy is affected by the presence of rock and leaf-litter cover. The data indicated that the species is restricted to the stream channel and does not seem to occupy forested areas that are distanced from the stream margins. Implications. Considering that H. fredi and many other congeneric species are listed as ‘Data Deficient’ in the IUCN Red List, it is important to define a threat category so as to conserve them. Many stream-associated species tend to have their occupancy overestimated, leading to an underestimation of their threat risk. This study systematically demonstrated that H. fredi has a strict and reduced occupancy, mostly limited to the stream margins, that should be considered when determining conservation efforts for this and ecologically similar species. [ABSTRACT FROM AUTHOR]

Miniaturisation is an important evolutionary trend for amphibians and has occurred several times in independent anuran lineages. Most miniaturised frogs live in the leaf litter of tropical forests and have terrestrial reproductive modes. They are expected to have reduced fecundity in number of eggs than larger-bodied related species, but little is known about reproductive cycles and proportion of reproductive females. Lower vagility is also assumed, however, as they are difficult to observe, there is little empirical evidence about their dispersal. We studied the reproductive biology (sex ratio, sexual size dimorphism and fecundity parameters) and population ecology (growth, dispersal, and phenology) of the miniature Guanabara Frog Euparkerella aff. brasiliensis (⩽ 20 mm). We collected and analysed 75 specimens of E. aff. brasiliensis , of which 27 were adult females with vitellogenic oocytes in their ovaries. Fecundity was low for number of eggs (average number = 9.7), but only one adult female had no vitellogenic oocytes. Sex ratio was relatively balanced among sexes, being female-biased (0.92) for all individuals and male-biased (1.17) for adults. Juveniles and ovigerous females were observed throughout the year during the two years of mark-recapture study, which indicates continuous breeding. We captured 121 individuals, of which 12% were recaptured in their original collection sites, suggesting low vagility. We discuss our findings considering the current knowledge about the ecology of miniaturised frogs and other Terraranae and suggest future directions for ecological studies and conservation planning. [ABSTRACT FROM AUTHOR]

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The article explores the spatial and temporal distribution of Pseudis minuta and the role of environmental factors in its reproduction in Reserva Biológica do Lami, Porto Alegre, southern Brazil. There were significant differences in border distance and water depth among age-sex classes of Pseudis minuta. No significant difference was found in the presence of calling males and non-calling males in relation to monthly relative humidity but opposite was noted in relation to total monthly rainfall, mean monthly air temperature and water temperature. The number of females was related with daily air temperature, relative humidity and water temperature.

The article offers information on the natural history and body size of the poorly known Brazilian tree frog Hypsiboas secedens. Topics discussed include the frog is found in Brazilian Atlantic rainforest, they reproduce in reproduce in lentic habitats, species is sexually dimorphic, females growing larger than males; and females have pigments oocytes in ovaries.

The article reports on the discovery of endoparasites in Boana secedens (Barro Branco Treefrog). Topics include the identification of Cosmocercidae nematodes and Physaloptera sp. larvae as parasites in this frog species, the first documentation of these helminths in B. secedens, and the methods used for examining and identifying these parasites from collected specimens.

Morphological similarity associated to restricted distributions and low dispersal abilities make the direct developing “Terrarana” frogs of the genus Euparkerella a good model for examining diversification processes. We here infer phylogenetic relationships within the genus Euparkerella, using DNA sequence data from one mitochondrial and four nuclear genes coupled with traditional Bayesian phylogenetic reconstruction approaches and more recent coalescent methods of species tree inference. We also used Bayesian clustering analysis and a recent Bayesian coalescent-based approach specifically to infer species delimitation. The analysis of 39 individuals from the four known Euparkerella species uncovered high levels of genetic diversity, especially within the two previously morphologically-defined E. cochranae and E. brasiliensis. Within these species, the gene trees at five independent loci and trees from combined data (concatenated dataset and the species tree) uncovered six deeply diverged and geographically coherent evolutionary units, which may have diverged between the Miocene and the Pleistocene. These six units were also uncovered in the Bayesian clustering analysis, and supported by the Bayesian coalescent-based species delimitation (BPP), and Genealogical Sorting Index (GSI), providing thus strong evidence for underestimation of the current levels of diversity within Euparkerella. The cryptic diversity now uncovered opens new opportunities to examine the origins and maintenance of microendemism in the context of spatial heterogeneity and/or human induced fragmentation of the highly threatened Brazilian Atlantic forest hotspot. [ABSTRACT FROM AUTHOR]

The current note reports the presence of Odontophrynus moratoi at municipality of São Carlos, state of São Paulo, southeastern Brazil. This is the third known locality of occurrence of this cycloramphid frog considered threatened of extinction. [ABSTRACT FROM AUTHOR]

Haddadus binotatus is an endemic anuran of the Brazilian Atlantic Forest and currently, there is no information about the diet of this species. We analyzed the diet of two populations of this anuran in two states in southeast Brazil. Samplings were carried out in 2004 in the state of Rio de Janeiro and in 2009 and 2010 in the state of Espírito Santo. Haddadus binotatus presented a rich diet composition, preying 19 prey types. Orthoptera, Coleoptera, and Blattodea were the most important preys in the Rio de Janeiro population, and Orthoptera, Araneae and Hemiptera were the most important in the Espírito Santo population. The diet composition differed numerically between the two localities, but not in terms of volume, which can reflect local differences in the prey availability in the two habitats. The jaw width limited the size of prey, which is expected for predators who swallow the preys without chewing. The proportion of individuals with empty stomachs was higher in the Rio de Janeiro population (39.2%) than in the Espírito Santo population (17.9%), suggesting that the former could be in a lower energy balance. The females of the species were larger than the males, which may result from the production of larger eggs.