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This study aims to evaluate the efficiency of electric fishing and seine-net/dip-net to obtain quantitative and qualitative data on the fish community of low conductivity streams in the semi-arid region of Bahia, Brazil. Samplings were collected in 15 streams in the region of Chapada Diamantina. Two homogeneous stretches with 50 m each were selected and closed with blocking nets. Zippin analysis was used to evaluate the suitability of each capture method. Differences in abundance, richness, composition of species, and length of specimens captured were compared for each method. Twenty-nine species were collected, twenty-four using electric fishing, and twenty-one using seine-net/dip-net. There were no significant differences between methods as for abundance, richness, composition of species, and length of the individual captured. There were no significant differences in capturability. Both methods have high values of sample efficiency (SE). Therefore, electric fishing and seine-net/dip-net are equally effective on describing qualitatively and quantitatively the fish community. It is noteworthy that for an ideal choice of collection method, the geomorphological characteristics of the streams must be taken into account since they exert a direct influence on both collection methods. [ABSTRACT FROM AUTHOR]

The genus Phyllodytes comprises eleven species strictly associated with bromeliads. Despite the fact that knowledge of the reproductive biology and natural history of a single species is important for any conservation and taxonomic issues, tadpoles and vocalisations of most species of Phyllodytes have not as yet been described. Herein we describe the tadpole (external and internal oral morphology) and the two different call types of Phyllodytes wuchereri. We conducted field surveys at the Serra da Jibóia, Elísio Medrado municipality, Bahia State. The tadpoles inhabit bromeliad phytothelms and have a depressed body, low fins, and a ventrally located oral disc that is bordered by a single row of marginal papillae with a wide anterior gap. The labial tooth row formula is 2(2)/4(1). We also provide field observations on the natural history of adults and tadpoles. The advertisement call has a mean duration of 4.3 ± 0.3 s and is emitted in series of 18 ± 2 multi-pulsed notes per call. A second call type was recorded and is herein referred to as courtship call. Finally, we compare our results with tadpole morphology and call data that is available for other Phyllodytes species. [ABSTRACT FROM AUTHOR]

Acoustic signals are the main communication vehicle for most anuran species, and males typically use advertisement calls to attract females and to interact with other males in a chorus. The role of the environment in the evolution of the advertisement call is still largely unknown, and the recognition of different selective pressures may improve our understanding of anuran communication system. The aim of this study was to investigate the effect of micro-habitat at calling sites on advertisement call structure and propagation in a population of the treefrog Hypsiboas crepitans. Males of this species typically call from elevated sites in vegetation or from sites where their body is partially submerged in water. Our analysis of call parameters of males calling from these sites showed that both dominant frequency and pulse rate were significantly lower when males called partially submerged in water compared to males calling from elevated sites in vegetation. Both pulse rate and dominant frequency have been shown to be important in species recognition among anurans, and they play a role in sexual selection and sound propagation. Our analysis of the effect of calling site (elevated or partially submerged) on signal propagation showed that the efficiency of transmission did not differ between sites. [ABSTRACT FROM AUTHOR]

Frostius pernambucensis and F. erythrophthalmus are cryptic bufonid species recognized mainly by the iris color: yellow in F. permambucensis and red in F. erythrophthalmus. However, field studies showed that the iris color of F. erythrophthalmus could vary between yellow and red. To improve the recognition of these species we described the advertisement call of Frostius pernambucensis and Frostius erythrophthalmus and we tested if call characteristics are influenced by temperature, male size and perch height. We also report on a physical interaction between two males of F. pernambucensis and the associated vocalization, suggesting that F. pernambucensis has not a territorial call or encounter call. Comparing the advertisement calls, the call of F. pernambucensis was lower, shorter and with a smaller number of notes than the call of F. erythrophthalmus. Dominant frequency and fundamental frequency variation of the F. pernambucensis advertisement call were related to the males size, while the call emission rate was related to air temperature. However, we could not find relationship among the acoustic characteristic of F. erythrophthalmus and male size or temperature. [ABSTRACT FROM AUTHOR]

Extended courtship and amplexus have been related either to readiness for spawning or to evaluation of the quality of egg-laying site. As preliminary observations revealed that a pair of C. stepheni can engage in two successive amplexi, an unusual pattern for dendrobatid frogs, we carried out experiments in the field to characterize this mating strategy. During the first hour after the first amplexus, we detect ovulation and changes in the oviduct morphology. The female could exhibit three different behavioural patterns, if disturbed after the first amplexus: remaining in the nest, leaving the nest and returning some minutes later, leaving the nest and subsequently enticed by their mate to another nearby nest. In cases where the male did not return for the second amplexus, the female sought another mate and engaged in a second amplexus. [ABSTRACT FROM AUTHOR]

The acoustic adaptation hypothesis (AAH) states that the acoustic signal of a species must propagate better in its native habitat. Studies have shown that certain anuran species modify acoustic parameters according to the environment where they are calling. However, these studies did not verify if these modifications improved the call's transmission. We investigated whether advertisement calls of Pithecopus nordestinus (Phyllomedusidade)propagated more efficiently in two habitats where the species has evolved over generations (Caatinga and Atlantic Forest) and, according to the predictions of the AAH, whether specific acoustic parameters (number of pulses, interval between pulses and dominant frequency) maximise transmission. We measured the efficiency of the transmitted signal (natural and synthesised calls) in different environments. Our results showed that natural calls from Caatinga habitats were less degraded. We found that synthetised calls with shorter intervals between pulses propagated just as well in both the Caatinga and the Atlantic Forests. Finally, the dominant frequency was influenced by the propagation environment and, synthetised calls with higher frequencies showed less degradation when propagated in the Caatinga. Our results indicate that not all differences found in the acoustic parameters of anuran calls in distinct environments can be attributed to the acoustic adaptation hypothesis. [ABSTRACT FROM AUTHOR]

Understanding the variability of acoustic signals is a first important step for the comprehension of the evolutionary processes that led to current diversity. Herein, we evaluate the variability of the advertisement call of the phyllomedusid species from the genera Phyllomedusa Wagler, 1830 and Pithecopus Cope, 1866 at different levels: intra-individual, intra-population, inter-population, intra-species, and inter-specific. An analysis of coefficients of variation showed a continuum of variability between the acoustic parameters analyzed, from static to highly dynamic. The majority of the variation was attributed to the inter-specific level, while call parameters at the intra-individual level varied the least. However, each parameter behaved differently with call interval being the most variable across all levels. Most temporal acoustic parameters were affected by environmental temperature, while pulse rate and dominant frequency were strongly influenced by body size. Only pulse rate was correlated to the geographic distance between populations, while all parameters presented a significant phylogenetic signal. Based on these results, we discuss the possible importance of different evolutionary forces and the usage of vocalizations for taxonomic purposes. [ABSTRACT FROM AUTHOR]

The acoustic adaptation hypothesis (AAH) predicts that acoustic signals are selected to propagate more efficiently in the habitat where they are normally transmitted. Several studies corroborated the AAH for primates and birds, but evidence for frogs is contentious: While most studies failed to support the AAH, recent studies have shown that within‐species variation conforms to the predictions of the AAH. Herein, we test the AAH by comparing advertisement calls of Phyllomedusa nordestina from two contrasting habitats (Atlantic Rainforest and Caatinga) and by testing the influence of the amount of vegetation around calling sites on acoustic parameters of frog calls. The interval between pulses was significantly different between individuals from the Atlantic Rainforest and from the Caatinga, and the number of pulses was correlated with the amount of vegetation around calling sites. Hence, our results indicate that multiple evolutionary forces may act simultaneously on the advertisement calls of frogs. [ABSTRACT FROM AUTHOR]

An inventory of the amphibians of the Reserva Ecológica Michelin - REM in southern Bahia, Brazil is presented. Sixty-nine species were recorded during a ten-year sampling period. Amphibians were distributed in two orders (Gymnophiona and Anura), belonging to twelve families [Aromobatidae (1), Bufonidae (3), Centrolenidae (1), Craugastoridae (5), Eleutherodactylidae (3), Hemiphractidae (2), Hylidae (34), Phyllomedusidae (5) Leptodactylidae (7), Microhylidae (4), Odontophrynidae (3) and Caeciliidae (1)]. Fifty per cent of the reproductive modes known for Atlantic forest anurans were recorded. While no threatened species were found at REM, six species are classified as data deficient (DD) by the Brazilian Red List of threatened species and deserve additional attention. Phasmahyla timbo and Vitreorana eurygnatha are listed as endangered in Bahia according to the list of threatened species of the state. Despite a higher diversity of amphibians in the Atlantic forest having been reported for mountainous regions, our results revealed that amphibian richness for lowland forests is also high. [ABSTRACT FROM AUTHOR]

Advertisement calls can be used to aid solving taxonomic problems and understanding the evolution of certain groups. In this study, the advertisement call of Eleutherodactylus bilineatus is described. It is composed by two different notes with a total duration of 0.529-4.241 seconds and dominant frequency of 1.72-3.45 kHz. Additionally, new data is provided on the geographical distribution of Eleutherodactylus bilineatus and the most inland record for this species. [ABSTRACT FROM AUTHOR]

Acoustic signals are an important part in the behaviour of many species and may play a key role in speciation. However, little is known about the importance of natural selection on the evolution of such signals. Acoustics signals are the main communication channel for most anuran species, and background noise from streams is a constant source of masking interference for species reproducing in these environments. Herein, we test if the noise of flowing water habitats has favoured advertisement calls with higher dominant frequencies in frogs. Phylogenetic generalized least square model analysis revealed a significant influence of reproductive environment and body size on dominant frequency, with no significant interaction between habitat and body size. While stream breeders call at higher dominant frequencies, this acoustic parameter is inversely correlated with body size in both environments. We discuss the biological consequences of long-term adaptive shift in this acoustic parameter and possible trade-offs with other evolutionary forces. [ABSTRACT FROM AUTHOR]

The study of the diet of tadpoles can provide important information about the maintenance and dynamics of populations and communities of tropical amphibians. Tadpoles are in general herbivores and consume mostly algae. Despite this, little is known about how specific guilds use resources that are available in the same space and at the same time. It is thought that species of tadpoles segregate based on food use, especially in lotic environments where food resources may be a limiting factor. Conversely, it is believed that the use of food resources is similar among tadpoles with the same ecomorphotype. This study examined the diet ofAplastodiscus cavicola,Aplastodiscus sibilatusandBokermannohyla caprasyntopic tadpoles, as similarities may exist between these benthic species, all of which are adapted to the flow of water. This study was undertaken in the Michelin Ecological Reserve, municipality of Igrapiúna, state of Bahia, Brazil. To analyze the diet of the tadpoles, nonmetric multidimensional scaling (NMDS) was performed to evaluate the similarity between the diets of the species. Analysis of similarity (ANOSIM) was carried out to detect whether diet differed among tadpole species. The diet of these tadpoles consists mainly of algae, especially diatoms, plants, protozoa, fungi and microscopic animals. The NMDS identified three clusters representing the three species studied. ANOSIM detected significant differences among the diets of the species, which indicates partition of food resources. [ABSTRACT FROM AUTHOR]

The Middle Jaguaribe River region is a poorly sampled area in the Caatingas domain, located in the eastern Ceará State, northeastern Brazil. The Brazilian government agencies considered this region as a priority area for conservation and inventories. In order to fill this biodiversity knowledge gap, we conducted a ten-day rapid inventory of the anuran fauna from April 11 to 20, 2014, surveying different physiognomies of the region. We recorded 19 anuran species belonging to five families: Bufonidae (2), Hylidae (5), Leptodactylidae (9), Microhylidae (2) and Odontophrynidae (1). Most inventories of Caatinga amphibians published to date have been conducted inside protected areas and/or of high altitude (mesic areas known as "brejos de altitude"). The list we present herein contributes to the knowledge of lowland Caatinga sites outside protected areas. We discuss our results in light of taxonomic and geographic features of the anurans sampled. [ABSTRACT FROM AUTHOR]

Abstract: Despite major progress in deciphering the amphibian tree of life by molecular phylogenetics, we identified two questions remaining to be answered regarding relationships within Hyloidea, the clade of South American origin that comprises most extant anuran diversity. A few genera like Rupirana and Crossodactylodes have enigmatic phylogenetic positions, and relationships among major lineages within some families like Leptodactylidae remain ambiguous. To resolve these specific questions we used two approaches (1) a complete matrix approach representing >6.6kb, including most major Hyloidea lineages (61 terminals) combining different methods of phylogenetic reconstruction and measures of node support; and (2) a supermatrix approach >11.6kb with a focus on Leptodactylidae. Both Rupirana and Crossodactylodes are unambiguously grouped with Paratelmatobius and Scythrophrys. The clade comprising these four genera is named Crossodactylodinae and embedded within Leptodactylidae. Crossodactylodinae is moderately supported as sister group of Leptodactylinae from (1) and as the sister group of the other Leptodactylidae from (2) with low support. Genera within Crossodactylodinae are scattered along a north–south axis in the Atlantic forest and their origins are very ancient (Paleocene). Such results stress the importance of the northern Atlantic forest in terms of conservation. Moreover, the position of Pseudopaludicola, which is well supported as the sister group to all other Leiuperinae, suggests that foam-nest building may have arisen independently in Leptodactylinae and Leiuperinae. Moreover, in spite of being of similar age, foam-nest builders are more widespread than nonfoam-nest breeders and have higher species diversity. Nevertheless, the bulk of the diversity within foam-nest breeders arose some 20Myr later than the character itself. [Copyright &y& Elsevier]

• The Pristimantis from Atlantic Forest comprises nine different lineages. • The main splits of this group began at Eocene and continued through Miocene. • Splits may be linked to climatic fluctuations at Eocene-Oligocene and Pleistocene. The Neotropical region is known both for its megadiverse fauna and for the significant deficiency of our knowledge on species limits. The Amazon and Atlantic Forest are the two most diverse and large rainforests in South America, and they harbor many groups of sister species and sister genera. The frog genus Pristimantis is the most speciose genus of terrestrial vertebrates with 546 species, but only three of them occur in the Atlantic forest. Herein, we investigate the diversification history and phylogenetic relationship among the Atlantic Forest Pristimantis lineages in a spatial-temporal framework, using mitochondrial and nuclear genes. Our results reveal a remarkable hidden diversity, with nine highly structure lineages that may correspond to undescribed species, with many cases of sympatry among these divergent lineages. Atlantic forest Pristimantis form a monophyletic group that started to diversify over 40 million years ago. This ancient group shows diversification events that remount the early bursts of the Atlantic Forest diversification history, as well as lineage diversification likely resulting from recent Pleistocene climatic fluctuations. Future work must concentrate in comparing these lineages under an integrative framework including morphology, advertisement calls and other ecology traits to confidently delimit species of Pristimantis in the Atlantic Forest. [ABSTRACT FROM AUTHOR]