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Predator-prey interactions have been suggested as drivers of diversity in different lineages, and the presence of anti-predator defences in some clades is linked to higher rates of diversification. Warning signals are some of the most widespread defences in the animal world, and there is evidence of higher diversification rates in aposematic lineages. The mechanisms behind such species richness, however, are still unclear. Here, we test whether lineages that use aposematism as anti-predator defence exhibit higher levels of genetic differentiation between populations, leading to increased opportunities for divergence. We collated from the literature more than 3000 pairwise genetic differentiation values across more than 700 populations from over 60 amphibian species. We find evidence that over short geographical distances, populations of species of aposematic lineages exhibit greater genetic divergence relative to species that are not aposematic. Our results support a scenario where the use of warning signals could restrict gene flow, and suggest that anti-predator defences could impact divergence between populations and potentially have effects at a macro-evolutionary scale.

Advertisement calls in frogs have evolved to be species-specific signals of recognition and are therefore considered an essential component of integrative taxonomic approaches to identify species and delineate their distribution range. The species rich genus Microhyla is a particularly challenging group for species identification, discovery and conservation management due to the small size, conserved morphology and wide distribution of its members, necessitating the need for a thorough description of their vocalization. In this study, we provide quantitative description of the vocal behaviour of Microhyla nilphamariensis, a widely distributed south Asian species, from Delhi, India, based on call recordings of 18 individuals and assessment of 21 call properties. Based on the properties measured acrossed 360 calls, we find that a typical advertisement call of M. nilphamariensis lasts for 393.5 ±  57.5 ms, has 17 pulses on average and produce pulses at rate of 39 pulses/s. The overall call dominant frequency was found to be 2.8 KHz and the call spectrum consisted of two dominant frequency peaks centered at 1.6 KHz and 3.6 KHz, ranging between 1.5-4.1 KHz. Apart from its typical advertisement call, our study also reveals the presence of three rare call types, previously unreported in this species. We describe variability in call properties and discuss their relation to body size and temperature. We found that overall dominant frequency 1 (spectral property) was found to be correlated with body size, while first pulse period (temporal property) was found to be correlated with temperature. Further, we compare the vocal repertoire of M. nilphamariensis with that of the congener Microhyla ornata from the western coast of India and Sri Lanka and also compare the call properties of these two populations of M. ornata to investigate intra-specific call variation. We find statistically significant differentiation in their acoustic repertoire in both cases. Based on 18 call properties (out of 20), individuals of each locality clearly segregate on PCA factor plane forming separate groups. Discriminant function analysis (DFA) using PCA factors shows 100% classification success with individuals of each locality getting classified to a discrete group. This confirms significant acoustic differentiation between these species as well as between geographically distant conspecifics. The data generated in this study will be useful for comparative bioacoustic analysis of Microhyla species and can be utilized to monitor populations and devise conservation management plan for threatened species in this group.

Frogs are an ecologically diverse and phylogenetically ancient group of anuran amphibians that include important vertebrate cell and developmental model systems, notably the genus Xenopus. Here we report a high-quality reference genome sequence for the western clawed frog, Xenopus tropicalis, along with draft chromosome-scale sequences of three distantly related emerging model frog species, Eleutherodactylus coqui, Engystomops pustulosus, and Hymenochirus boettgeri. Frog chromosomes have remained remarkably stable since the Mesozoic Era, with limited Robertsonian (i.e., arm-preserving) translocations and end-to-end fusions found among the smaller chromosomes. Conservation of synteny includes conservation of centromere locations, marked by centromeric tandem repeats associated with Cenp-a binding surrounded by pericentromeric LINE/L1 elements. This work explores the structure of chromosomes across frogs, using a dense meiotic linkage map for X. tropicalis and chromatin conformation capture (Hi-C) data for all species. Abundant satellite repeats occupy the unusually long (~20 megabase) terminal regions of each chromosome that coincide with high rates of recombination. Both embryonic and differentiated cells show reproducible associations of centromeric chromatin and of telomeres, reflecting a Rabl-like configuration. Our comparative analyses reveal 13 conserved ancestral anuran chromosomes from which contemporary frog genomes were constructed.

During their development, amphibians undergo various physiological processes that may affect their susceptibility to environmental pollutants. Naturally occurring fluctuations caused by developmental events are often overlooked in ecotoxicological studies. Our aim is to investigate how biomarkers of oxidative stress are modulated at different stages of larval development in the Amazonian amphibian species, Physalaemus ephippifer. The premetamorphosis, prometamorphosis and metamorphic climax stages were used to analyze total antioxidant capacity (ACAP), glutathione S-transferase (GST) activity, lipid peroxidation (LPO) levels and the expression of genes nrf2, gst, gsr (glutathione reductase) and gclc (glycine-cysteine ligase, catalytic subunit). Although there was no difference in ACAP and the genes expression among the studied stages, individuals from the premetamorphosis and prometamorphosis showed higher GST activity than ones under the climax. LPO levels were highest in individuals from the metamorphic climax. The present study suggests that the oxidative status changes during ontogeny of P. ephippifer tadpoles, especially during the metamorphic climax, the most demanding developmental phase. Variations in the redox balance at different developmental stages may lead to a divergent response to pollution. Therefore, we recommend that studies using anuran larvae as biomonitors consider possible physiological differences during ontogeny in their respective analyses. [ABSTRACT FROM AUTHOR]

Variation in environmental chemistry affects animal health and demographics. For instance, acidification of aquatic ecosystems (e.g., due to acid rain) can have consequences for organismal fitness. Elevated atmospheric concentrations of CO2, which reacts with water to produce carbonic acid, may affect aquatic animal physiology in multiple ways, including via reductions in pH. Such impacts have been assessed to a large extent in marine systems. Similar effects are also likely occurring in freshwater ecosystems but are relatively understudied. The goal of this project was to determine how changes in pH and CO2 concentrations influence traits and survival of animals in freshwater systems, using larval American Bullfrogs (Lithobates catesbeianus (also known as Rana catesbeiana) [Shaw, 1802]) as a model. We hypothesized that elevated CO2 concentrations and reduced pH negatively affect larval frog immune function, growth, and survival, which we tested in a laboratory aquarium experiment. Over the 27-d experiment, tadpoles were exposed to 4 treatments: 1) near-neutral pH and no gas addition (mean ± SE pH = 7.17 ± 0.05), 2) CO2 gas sparged into aquariums (pH = 5.32 ± 0.04), 3) acidified water without gas addition (pH = 6.29 ± 0.08), and 4) ambient air sparged into aquariums (control for effects of gas addition) at near-neutral pH (pH = 7.46 ± 0.03). We measured tadpole innate immune response, growth, and survival. Results from the experiment partially supported our hypothesis, with lower immune function in tadpoles exposed to acidified water or elevated CO2 compared with the control treatments and lower final mass and survival under elevated CO2. These findings motivate additional research on pH and CO2 effects on freshwater animals and suggest that increased environmental acidity and elevated CO2 can lead to negative impacts, which could contribute to reductions in wildlife health and population declines in light of ongoing environmental changes. [ABSTRACT FROM AUTHOR]

The Pliocene lacustrine infill of Camp dels Ninots maar (Girona, Spain) hosts an exceptional record of complete articulated skeletons. Here we present the taphonomical description of 22 fossil water frogs recovered from the Pit 7/8 of Can Argilera Sector. Description of their skeletal taphonomy is done on the basis of their distribution, completeness, articulation and limb position, and by establishing comparisons with the late Miocene site of Libros (Spain). Microscopic examination shows no evidence of digestion and absence of weathering. Mass mortality or any environmental stress-induced factors cannot be ruled out, but natural death seems to be the most probable. Limited time of decay prior burial seems to be the main pattern explaining the relatively high degree of articulation and completeness. Floatation is not to be disregard for some more (proximally) disarticulated specimens. Taphonomical patterns document two types of sub-environments inside a cool and deep lake, suggesting a more complex depositional scenario for Camp dels Ninots than the ones described in others similar Konservat-Lagerstätten. [ABSTRACT FROM AUTHOR]

We revise the systematics of the ranid frogs of the genus Hylarana occurring on Halmahera Island, Northern Moluccas of eastern Indonesia based on molecular and morphological data. Our results show that two distinct species each being nested within two distinct clades (hereafter papua clade and celebensis clade) exist on the island. One corresponds to H. moluccana (celebensis clade) and the other one to an unnamed species (papua clade) that we describe herein. The new species is genetically distinct from all congeners of the papua clade by p distances ranging from 6.9% to 11.5% on the 16S rRNA gene. Morphologically, the new species can be distinguished from all congeners by having the following combination of characteristics: A large species with adult males reaching a maximum snout-to-vent length (SVL) 67.3 mm; vomerine teeth in two oblique rows with narrow interodontophore distance; snout rounded dorsally; dorsum with few scattered cone-shaped tubercles that are black with white tips; distinct skin folds (ridges) on the dorsal side of the thigh coinciding with dark brown cross bars; a marbled pattern on the ventral side of thigh and yellowish groin. Here we provide a redescription for H. moluccana based on its lectotype from Ternate. We also provide new occurrence records for H. daemeli, H. volkerjane, and H. arfaki from the western part of mainland Papua. Furthermore, we demonstrated that H. celebensis harbors multiple mtDNA lineages suggestive of cryptic diversity within the celebensis clade. The occurrence of two distinct species from Halmahera calls for further research on the biogeographic history of Hylarana in Northern Moluccas. [ABSTRACT FROM AUTHOR]

Despite acoustic signals playing a fundamental role on animal behavior and reproduction, our understanding of the mechanisms driving their evolution is still scarce. Due to the high cost of signaling, several adaptive bioacoustics hypotheses have been proposed to explain call design. While Acoustic Adaptation Hypothesis (AAH) postulates the habitat influence on shaping acoustic signals, Morphological Adaptation Hypothesis (MAH) emphasizes the constraints that animal structure imposes to their calls. Yet, when testing those hypotheses, phylogenetic comparative methods have been scarcely applied so far. Here we evaluated the AAH and MAH in 163 anurans (i.e., Brazilian species of the family Hylidae), based on a broad review of the dominant frequency of their advertisement calls. Comparative methods revealed a negative relationship between dominant frequency and body size, supporting the MAH. AAH was partly rejected, as vegetation density, habitat type and calling microhabitat did not affect species' dominant frequency. However, species calling from higher perches had higher dominant frequencies, partially supporting habitat effect on call features. Our results not only highlight the role of morphology on shaping Hylidae call design, but also arise questions about scale effect, behavioral strategies and other sound propagation characteristics while testing AAH in frogs. [ABSTRACT FROM AUTHOR]

This article provides a detailed description of the tadpole of the Hyloxalus nexipus frog species, focusing on its geographic variation and morphological characteristics. The researchers collected specimens from Ecuador and Peru and examined their coloration and measurements. The document emphasizes the importance of studying tadpoles in understanding anuran species. It also discusses the morphology and characteristics of tadpoles belonging to the Hyloxalus genus of poison dart frogs, noting specific differences in the upper jaw sheath and the position of the upper fin in Hyloxalus nexipus tadpoles. The information is based on detailed observations of single specimens in different developmental stages and references other relevant studies on tadpole morphology and taxonomy. [Extracted from the article]

Anurans have several characteristics in their acoustic communication that distinguish them. These characteristics are influenced by body-related, environmental and social variables. However, the complexity of anuran repertoire and the effect of such variables on it are still understudied. Dendropsophus minutus is a Neotropical treefrog that has a wide repertoire composed of three notes, grouped in at least 71 unique combinations. To quantify complexity, we used the entropy measurement, since it measures the randomness of a sequence. Therefore, we could test if repertoire complexity in D. minutus is related with body condition, social context, and environmental variables. We recorded vocalisations of 80 males in three sites and found 44 unique note combinations not described before, increasing the species' repertoire to 115 combinations. We observed that the species has near maximum entropy for note frequency, but a low entropy for note sequencies, showing a clear a bias for some note combinations. We found a positive relationship between repertoire complexity and air temperature. Thus, based on our results, the complexity of this species' repertoire is an additional trait influenced by climate, and should be considered in future studies. [ABSTRACT FROM AUTHOR]

A group of fanged frogs from Southeast and East Asia has long been considered a single widespread species Limnonectes kuhlii, but occurrence in this group of many cryptic species has recently been demonstrated mainly in the continent through molecular phylogenetic analyses. This led to similar analyses of populations from other parts of the known range, and phylogenetic relationships inferred for frogs from the island of Borneo through mitochondrial and nuclear DNA resulted in the presence of nearly 20 distinct lineages. We studied morphological variation in 13 of these lineages from the Malaysian part and confirmed their taxonomically distinct statuses. We applied existing names to three of them, L. conspicillatus, L. kong, and L. mocquardi, and described 10 remaining ones as new species. [ABSTRACT FROM AUTHOR]

By selecting appropriate microhabitats, animals gain various benefits. For amphibians, which are ectothermic, appropriate microhabitat selection is directly related to their survival. This study aims to characterize the microhabitat type selected by Bufo gargarizans in South Korea, which has not yet been examined, using radiotelemetry. We analyzed the percent cover of different microhabitat features at sites where B. gargarizans was found. The microhabitat was categorized into eight types: stacked dry leaves litter or hay, grass, naked field, stones/pebbles, fallen branches, alive or dead trees/shrubs, wetland, and other. We collected a total of 60 location data, all of which had closed cover. From these, nine hibernation sites and six post-breeding dormancy sites were identified. Dry leaf litter was found to be the most frequently selected microhabitat type. We also found significant differences in microhabitat type between the hibernation period and the post-breeding dormancy period. We considered that these differences can be explained by the ecological characteristics of B. gargarizans. [ABSTRACT FROM AUTHOR]

The genus Ozolaimus is characterised by presenting a dorsoventrally elongated mouth with two lateral lips, a very long oesophagus consisting of anterior portion strong and short, with a fusiform fold, and a thin posterior portion ending in a distinct bulb, an anteriorly dilated intestine, and absent lateral wings. Between February 2014 and September 2016, 11 specimens of the anuran Corythomantis greeningi were collected manually at the Ecological Station of Aiuaba, Ceará State, Brazil. After analysis, nine specimens of Ozolaimus cirratus infecting the large intestine of the referred specimen were recorded. Knowledge is still scarce about the ecological dynamics of pharyngodonid parasites and their parasitehost relationships; thus, this work is the first to record members of the genus Ozolaimus infecting the casqueheaded tree frog Corythomantis greeningi from the Caatinga biome. Previously, the only registered hosts of Ozalaimus parasites were iguanid lizards. [ABSTRACT FROM AUTHOR]

Mutualistic and similar ecological associations between tarantulas (Mygalomorphae: Theraphosidae) and other animals are reviewed. Such associations are found to occur in at least nine theraphosid subfamilies. We present 63 new cases of theraphosid–anuran associations from 10 countries, documenting these interactions for the first time in Brazil, Chile, the Dominican Republic, and the Philippines. These findings are the first documentation of such associations for 13 theraphosid and 20 anuran taxa. Additionally, we report, for the first time, associations potentially of mutualistic nature between tarantulas and snakes, whip spiders, and harvestmen. Furthermore, we provide new reports of associations with ants and termites. While some of these interactions appear to be merely tolerated cohabitations, those involving anurans and ants seem to be more prevalent and complex, clearly offering benefits for both organisms. Additionally, based on multiple observations and field experiments, we propose a new hypothesis regarding the evolution of hirsuteness in theraphosids as a defensive strategy against predatory ants. This hypothesis supports previous findings that suggest a similar function for urticating setae incorporated into egg sacs and moulting mats. We further document a unique escape strategy against ants in New World arboreal theraphosids. Finally, the possibility of a chemical defence mechanism through specialised epidermal glands in theraphosids is briefly discussed. [ABSTRACT FROM AUTHOR]

Olfaction is the oldest sense in the animal kingdom. It is used during a multitude of behaviours, such as the encounter of food, the detection of predators, the recognition of habitat‐related cues or the communication with conspecifics. While the use of olfaction and chemical communication has been studied widely in some animals, it is barely known in others. Anurans (frogs and toads), for example, are well known to use acoustic and visual senses, but their chemical sense is still largely understudied. Studies concerning the chemical sense in anurans have been mostly based on the use of semiochemicals in juvenile stages, while the information on adult anurans remains limited. In this study, we analysed the behavioural response of the Neotropical poison frog Ranitomeya sirensis (Sira poison frog, Dendrobatidae) when presented with the odours of prey, novel/prey‐luring fruit, habitat, conspecific faeces and heterospecifics. For this, we offered each of the odours by placing them into one of two testing tubes fixed in an arena, with the other tube left empty as a control. We then measured the time the frogs spent in the vicinity of the odour versus the control tube and calculated a response index. While the frogs did not show a significant avoidance or attraction towards most of the tested odours, they showed a strong response towards the heterospecific odour, which was significantly avoided. This is the first evidence of a poison dart frog responding towards the odours of adult heterospecific frogs. We consider potential reasons for this strong negative reaction, such as the interspecific competition avoidance hypothesis, and discuss our results in the context of other animal species being deterred or attracted by heterospecific chemical cues. [ABSTRACT FROM AUTHOR]

Simple Summary: Head and neck cancers are aggressive and challenging to treat due to the severe side effects and toxicity of current treatments. Bufalin, a natural compound from the Chinese toad, has shown promise in fighting various cancers but has not been thoroughly studied for head and neck cancers. Our research aims to explore how bufalin works against these specific cancer cells. By using different techniques, we discovered that bufalin could reduce cancer cell growth, induce cell death, and enhance the body's immune response against tumors. These findings suggest that bufalin could become a new, effective treatment option with potentially fewer side effects for patients with head and neck cancers. This research could pave the way for developing better therapies and improving outcomes for patients facing this difficult disease. Bufalin, a cardiotonic steroid derived from the Chinese toad (Bufo gargarizans), has demonstrated potent anticancer properties across various cancer types, positioning it as a promising therapeutic candidate. However, comprehensive mechanistic studies specific to head and neck cancers have been lacking. Our study aimed to bridge this gap by investigating bufalin's mechanisms of action in head and neck cancer cells. Using several methods, such as Western blotting, immunofluorescence, and flow cytometry, we observed bufalin's dose-dependent reduction in cell viability, disruption of cell membrane integrity, and inhibition of colony formation in both HPV-positive and HPV-negative cell lines. Bufalin induces apoptosis through the modulation of apoptosis-related proteins, mitochondrial function, and reactive oxygen species production. It also arrests the cell cycle at the G2/M phase and attenuates cell migration while affecting epithelial–mesenchymal transition markers and targeting pivotal signaling pathways, including Wnt/β-catenin, EGFR, and NF-κB. Additionally, bufalin exerted immunomodulatory effects by polarizing macrophages toward the M1 phenotype, bolstering antitumor immune responses. These findings underscore bufalin's potential as a multifaceted therapeutic agent against head and neck cancers, targeting essential pathways involved in proliferation, apoptosis, cell cycle regulation, metastasis, and immune modulation. Further research is warranted to validate these mechanisms and optimize bufalin's clinical application. [ABSTRACT FROM AUTHOR]

Our aim was to evaluate whether the richness and composition of anurans responded to the time of forest regeneration via secondary succession. We sampled the anuran community in a mosaic of areas at three different stages of secondary succession in the Atlantic Forest, southern Brazil. The anurans were collected from nine lentic ponds and from their margins up to a 50 m radius. The late secondary forest sheltered the higher species richness, followed by the primary forest. The spatial variation in species richness was related to the forest succession stage and predominance of arboreal vegetation on the pond edge. The species composition changed throughout the succession stages, regardless of the distance among areas. Along the gradient of forest succession, environmental changes have driven species distribution, limiting the occurrence of forest species and favoring the colonization of areas at the early succession stage by opportunist species. We could observe that the secondary forest succession was a determining factor in the anuran community structure, and with the advancement of the secondary succession, both richness and composition were partly restored. Thus, the conservation of secondary forests might be an efficient strategy to preserve the biodiversity in areas of the Atlantic Forest. [ABSTRACT FROM AUTHOR]

The treefrog Boana exastis was tentatively included in B. faber group based on its morphological similarity to B. lundii and B. pardalis. This species was only recently included in a molecular phylogeny, confirming its placement in this group; however, its phylogenetic relationships have been poorly explored. Herein, we describe the larval external morphology, buccopharyngeal cavity, and skeleton of B. exastis, and assess its phylogenetic placement and genetic similarity between disjunct populations. Additionally, we describe the larval skeleton of the two closely related species, B. lundii and B. pardalis. The larval morphology of B. exastis is congruent with the other Boana species, reinforcing a high larval similarity across species of the B. faber group. The three species showed differences in color and in rows of marginal papillae. Comparing the chondrocranium of the three species, we found that B. exastis is more similar to B. pardalis than to B. lundii, contrary to what has been previously proposed, based on acoustic data. Phylogenetically, B. exastis was found to be more related to B. pardalis than to B. lundii. Despite presenting a disjunct distribution, the populations of Boana exastis show a very low mitochondrial genetic divergence, indicating that they are the same taxon. [ABSTRACT FROM AUTHOR]

Despite the great diversity of Brazilian anuran species, there are still many knowledge gaps about the acoustic communication of these animals. Among the species, those classified as 'Data Deficient' have the greatest gaps in knowledge on their behavior. This is the case of Boana ericae, a species belonging to the Boana pulchella group, endemic to the Chapada dos Veadeiros National Park region, in the northeast of the state of Goiás, Central Brazil. Three distinct call types (A, B, and C) are currently known for B. ericae, with the type A call associated with attracting reproductive partners and the type C call presenting a territorial function. We recorded the vocalizations of 10 individuals of this species and found the presence of vocalizations composing three new note types (D, E, and F). Our results indicate that air temperature and body condition influenced the acoustic parameters of the advertisement and aggressive calls of this species. We also observed that some acoustic parameters of the advertisement calls can be used for individual recognition for showing greater variation among individuals than intra-individually. Our results add new information regarding the vocal repertoire in this species, expanding their known intra-individual classification of the acoustic parameters. [ABSTRACT FROM AUTHOR]

Reproductive strategies are one of the more fascinating aspects of Anuran biology and are likely affected by species habitat use and availability of reproductive sites. The Cerrado endemic Pithecopus oreades is a habitat specialist that reproduces in seasonal high-altitude rocky streams in Central Brazil. Herein, we describe its reproductive behavior based on observations made during two consecutive reproductive seasons in a high-altitude stream located in an open field area in Central Brazil. The reproductive activity of P. oreades occurs during the rainy season, from the very first rains, and lasts about 3 months. The species is nocturnal, showing a vocalization peak between 20:00 h and 21:00 h. Its vocalization activity was related to total precipitation. The nests, composed by only one folded leaf, are placed on shrubs along streams. The nests, which hang over the stream pools, contain approximately 30 eggs that last about 13 days of incubation, producing about 25 tadpoles per spawning. Males are territorial, remaining in the same places for more than 60 days, defending them through vocalizations and eventual physical combats. Males with a higher body condition usually stay longer in the same territory. We also recorded males displaying satellite behavior. [ABSTRACT FROM AUTHOR]

In addition to the type locality (the summit of Aprada-tepui, Bolívar State of Venezuela), the distribution of the egg-brooding frog Stefania satelles was long thought to include several isolated tabletop mountain (tepui) summits surrounding the large Chimantá Massif in Bolívar State (hence the Latin name "satelles"). However, multilocus molecular phylogenetic analyses have revealed that this taxon includes several undescribed morphologically cryptic species, and that S. satelles should be restricted to its type locality. Two tepui-summit species confused under that name in the literature remain to be named, and the present paper aims at describing these populations previously referred to as Stefania sp. 3 and S. sp. 5. Stefania sp. 3 is only known from the small summit of Angasima-tepui, while S. sp. 5 is only reported from the small summit of Upuigma-tepui, both mountains being located south of the Chimantá Massif. These new, phylogenetically distinct species are described based on external morphology and osteology and in comparison to close relatives in the S. ginesi clade, which consists exclusively of tepui summit species. Both new species have highly restricted geographic ranges (less than 3 km2) and should be listed as Critically Endangered according to IUCN criteria. [ABSTRACT FROM AUTHOR]

Background: Kurixalus lenquanensis Yu, Wang, Hou, Rao and Yang, 2017 was originally described, based on 14 adult male specimens from Lengquan Village, Mengzi, Yunnan, China. So far, this species is known only from south-eastern Yunnan and information on females of this species is not available. During the field surveys in 2023, two Kurixalus specimens (one female and one male) were collected from central eastern Yunnan (Shilin, Kunming, Yunnan, China). These two specimens were confirmed to be K. lenquanensis by molecular phylogenetic analyses, based on 16S rRNA sequences. New information: A female specimen of K. lenquanensis is described for the first time and morphological variation amongst populations of this species is provided. The diagnosis and distribution of this species are updated. [ABSTRACT FROM AUTHOR]

The Chinese horned toads, Boulenophrys boettgeri (Boulenger, 1899) and Boulenophrys kuatunensis (Pope, 1929), are two captivating species within the family Megophryidae, which inhabit the mountainous streams in the Eastern of China. In this study, two new complete mitochondrial genomes of B. boettgeri and B. kuatunensis were sequenced, assembled, and annotated using next-generation sequencing. The length of mitochondrial genomes of B. boettgeri and B. kuatunensis was 16,597 and 17,921 bp, respectively, with both containing 13 protein coding genes, 22 tRNA genes, two rRNA genes, and one putative control region. Phylogenetic relationships based on protein-coding mitochondrial genes showed that the two Boulenophrys species formed a cluster with other Boulenophrys species. The two new sequences provide valuable insights into the mitochondrial genomes of these two species, offering important data for understanding the phylogenetic relationships of the genus Boulenophrys. [ABSTRACT FROM AUTHOR]

Within the breeding sites of anurans, factors at the microhabitat scale can exhibit variations over the years, resulting in temporal fluctuations within these sites. These fluctuations may lead to modifications in “normal larval development” and observable phenotypic changes. These developmental alterations appear to have evolved as shared strategies for achieving reproductive success and ensuring the survival of offspring. In a population of Boana cordobae inhabiting the Central Pampean Sierras (Córdoba, Argentina), the coexistence of pre‐ and prometamorphic tadpoles throughout the year, coupled with variations in size and shape within the same developmental stage, has led us to question about the duration of the larval period, variations in the timing of developmental events, and the possible existence of distinct larval morphs for this species. Utilizing data collected over four consecutive years from various locations, we described the development, growth, and larval morphology using both linear and geometric morphometrics during the pre‐ and prometamorphic stages. Our aim was to comprehend how anuran larvae in predictable environments synchronize the timing of their phenotypic transformations with external conditions. We identified two distinct cohorts: spring–summer and autumn–spring, each exhibiting distinct rates of growth and development until metamorphosis, resulting in size discrepancies. Moreover, the physical attributes of the breeding sites influenced the size of the tadpoles. However, the observed variation in shape was not related to the ontogenetic period, cohort, or developmental site. Ultimately, the observed variations had no impact on the morphology at metamorphosis. The comprehensive data gathered from our observations in B. cordobae yield valuable insights that contribute to a deeper comprehension of anuran larval development under natural conditions where changes are predictable and follow a regular pattern throughout the year, ultimately maximizing reproductive success. [ABSTRACT FROM AUTHOR]

The palaeofauna of the Quaternary is mostly known from the mammals' record, while the herpetofauna is less represented. In the same way, in northeastern Argentina reptile fossils records are scarce, usually represented by preliminary communications. This paper focuses on the study of herpetofauna remains from the Isla El Disparito archaeological site. The faunal materials collected at the site revealed an increase in taxonomic diversity related to the Quaternary herpetofauna in the IED site, with over 50% of the bone remains represented by anurans and at least six recognized squamates taxa. The purpose of this study is to properly identify these new records of herpetofauna remains from northeastern Argentina during the Holocene as well as to provide a dichotomous key of postcranial remains for identifying extant squamates taxa in other Quaternary sites from Argentina. The identified squamate assemblage includes the lizard Ophiodes sp., the snake families Typhlopidae, Dipsadidae, Viperidae and undetermined colubroids, along with anuran bone remains (Anura indet. and ?Hylidae). Additionally, the findings contribute to a better understanding of the herpetological assemblage in Argentina, providing insights into the composition of South American squamates during the Quaternary. [ABSTRACT FROM AUTHOR]

Photoreceptor oil droplets (ODs) are spherical organelles placed most commonly within the inner segment of the cone photoreceptors. Comprising neutral lipids, ODs can be either non-pigmented or pigmented and have been considered optically functional in various studies. Among living amphibians, ODs were only reported to occur in frogs and toads (Anura), while they are absent in salamanders and caecilians. Nonetheless, the limited understanding of their taxonomic distribution in anurans impedes a comprehensive assessment of their evolution and relationship with visual ecology. We studied the retinae of 134 anuran species, extending the knowledge of the distribution of ODs to 46 of the 58 currently recognized families, and providing a new perspective on this group that complements the available information from other vertebrates. The occurrence of ODs in anurans shows a strong phylogenetic signal, and our findings revealed that ODs evolved at least six times during the evolutionary history of the group, independently from other vertebrates. Although no evident correlation was found between OD occurrence, adult habits and diel activity, it is inferred that each independent origin involves distinct scenarios in the evolution of ODs concerning photic habits. Furthermore, our results revealed significant differences in the size of the ODs between nocturnal and arrhythmic anurans relative to the length of the cones' outer segment. [ABSTRACT FROM AUTHOR]

The Late Miocene vertebrate fauna from the Entre Ríos Province, Argentina, comes from two units: the marine Paraná Formation and the Lower Member of Ituzaingó Formation (LMIF). This latter includes a lower conglomerate set, with fine quartz gravel, and clay and chalcedony clasts, and fossil remains, traditionally known as ‘Mesopotamiense’ or ‘Conglomerado osífero’. We present new fossil vertebrate remains from the LMIF at the Puerto Víboras locality (Hernandarias, Entre Ríos Province) including Leptodactylus sp. (Amphibia, Anura), Crocodylia indet. Caimaninae indet. and Paranasuchus gasparinae (Alligatoridae), Chelidae indet. (Testudines, Pleurodira), Chelonoidis sp. (Testudines, Cryptodira), Plohophorus paranensis (Cingulata, Glyptodontidae), and Macraucheniinae indet. (Macraucheniidae, Litopterna). The record of Leptodactylus sp. represents the oldest record of the genus and the first amphibian record for the Neogene of the Entre Ríos Province. The material described herein and assigned to Chelonoidis sp. allows to confirm for the first time the presence of a testudinid in the Late Miocene of the Entre Ríos Province. [ABSTRACT FROM AUTHOR]

Colour signals play pivotal roles in different communication systems, and the evolution of these characters has been associated with behavioural ecology, integumentary production processes and perceptual mechanisms of the species involved. Here, we present the first insight into the molecular and histological basis of skin colour polymorphism within a miniaturized species of pumpkin toadlet, potentially representing the lowest size threshold for colour polytypism in tetrapods. Brachycephalus actaeus exhibits a coloration ranging from cryptic green to conspicuous orange skin, and our findings suggest that colour morphs differ in their capability to be detected by potential predators. We also found that the distribution and abundance of chromatophores are variable in the different colour morphs. The expression pattern of coloration related genes was predominantly associated with melanin synthesis (including dct, edn1, mlana, oca2, pmel, slc24a5, tyrp1 and wnt9a). Up‐regulation of melanin genes in grey, green and brown skin was associated with higher melanophore abundance than in orange skin, where xanthophores predominate. Our findings provide a significant foundation for comparing and understanding the diverse pathways that contribute to the evolution of pigment production in the skin of amphibians. [ABSTRACT FROM AUTHOR]

Anurans are widely diversified in South Africa, with more than 150 recognised species across the country. However, most the known fossil records of anurans are concentrated in the southern part of South Africa, within the rich Pliocene site of Langebaanweg. Isolated anuran elements have been recovered in the Pliocene deposits of the Cradle of Humankind, but none from the multi-localities site of Bolt’s Farm (Plio-Pleistocene). A small block containing an articulated anuran specimen was recently discovered from the Milo A site from Bolt’s Farm. We analysed this specimen using CT-scanning to describe its osteology. Surprisingly, the cavity housing the skeleton took the shape of the body of the individual, revealing a small sized individual with a triangular-shaped head. The preserved skeletal elements (around 50% of the skeleton) shows clear synapomorphies of the Ranoidea. A comparison between our specimen and members of all South African ranoid families allow us to highlight numerous osteological similarities between our specimen and taxa of the Pyxicephalidae, leading to a putative attribution to this large African family. In addition, the position of the body is identical to the position of a dormant pyxicephalid, suggesting that our specimen died during a dormancy period, in the dry season. This supports the current paleoenvironment reconstruction, an open savannah with marked seasonality. [ABSTRACT FROM AUTHOR]

Urban environments expose wildlife to levels of anthropogenic noise they would not experience in rural areas (e.g., traffic noise), and research suggests that many species adjust their acoustic signals for optimal transmission in urban soundscapes. However, our understanding of anuran (order Anura) responses to noise pollution in urban environments of the southeastern United States is limited, particularly for species that can breed during winter. Our goal was to examine how vocal anuran advertisement call characteristics during winter varied with increasing distance from roadways in bottomland hardwoods of Louisiana, USA. We deployed acoustic recording units at two sites (i.e., rural and urban) perpendicular to Interstate 10 at 200‐, 400‐, and 600‐m intervals (i.e., close, middle, and far) from November 2019 to January 2020. We detected Cajun Chorus Frogs (Pseudacris fouquettei) and Cricket Frogs (Acris spp.) at our rural site, and only detected Cricket Frogs at our urban site. At the rural site, Cajun Chorus Frogs produced longer duration notes at the far location compared to the middle location. At the urban site, Cricket Frogs produced higher dominant frequency calls at the close location compared to the far and middle locations and longer duration notes at the far location compared to the close location. We were unable to account for additional factors in our models (e.g., temperature, noise levels), but our results generally align with previous research. Our study provides baseline data for future research to examine the potential effects of traffic noise on winter advertisement calls in locations with similar environmental conditions and species. [ABSTRACT FROM AUTHOR]

This study aims to characterize the gonads, folliculogenesis, and spermatogenesis processes of male and female Rhinella bergi through anatomical, histological and morphometric analysis. We worked with specimens previously collected in the spring and summer seasons (2014-2015), in which the gonads were studied based on morphological, histological and morphometric analysis. The reproductive system was analyzed using a stereoscopic microscope and a scanning electron microscope (SEM). Histological preparations were made following the conventional protocol of dehydration, inclusion in paraffin and stained with haematoxylin-eosin, Mallory trichrome and PAS histochemical reactions. The anatomical and morphometric characteristics and the gametogenesis in R. bergi agree with what was proposed for other analyzed species of the Bufonidae family. Females with ovaries with oocytes in different stages of maturity and postovulatory females were found. The males presented continuous spermatogenesis. The results of this work serve as a basis for the characterization of the reproductive cycle in R. bergi and, at the same time, provide background information on the analysis of gametogenic activity. Future investigations will be focused on evaluating the reproductive cycle in this species, both in ovaries and testes as well as Bidder's organ, to compare and correlate with the results obtained in this study. [ABSTRACT FROM AUTHOR]

During the last decades several miniaturized frogs have been described from different parts of the world. Those frogs, measuring less than 25 mm, show similar miniaturization features as the loss of phalanges in both the anterior and posterior limbs and the reduction of bone elements. However, there seems to be a limit regarding the minimum size of frogs and here we wanted to find an answer to the question: which is the smallest amphibian in the world? In 2019, an endemic species of toad known only from two localities in southern Bahia, Brazil, was studied. When we compared the size of adult representatives of this species with those of other species discovered in various parts of the world in the last decade, we observed that individuals of Brachycephalus pulex are the amphibians with the smallest total length recorded, thus qualifying them to bear the title of the tiniest anuran amphibian, and also tiniest vertebrate in the world. [ABSTRACT FROM AUTHOR]

Understanding species composition across temporal and spatial scales through participatory monitoring has contributed to the development of several studies focused on biodiversity in Neotropical ecosystems. Habitat loss and the illegal collection of bromeliads pose significant threats to bromeligenous frogs, which depend on the rainwater collected between bromeliad leaves for egg and tadpole development. In this study, we compiled a comprehensive dataset of bromeligenous frogs using data from "Projeto Bromélias" on the iNaturalist citizen science platform. Our dataset includes records of 85 species of bromeligenous frogs, representing 52% of the 164 known species that reproduce in bromeliads. These species belong to 33 genera and 10 families and are reported from 18 countries. Twenty-eight species are listed in threatened categories on a global scale. Our findings extended the known geographic distribution of four species. Notably, the green and black poison dart Frog, Dendrobates auratus, was recorded as a non-native species in Hawaii, USA. Regarding the temporal data, the number of bromeligenous records increased substantially after 2009. This study highlights the value of citizen science platforms as important tools for monitoring bromeliad inhabitants and contributing to management and conservation initiatives. [ABSTRACT FROM AUTHOR]

The Chinese horned toads, Boulenophrys boettgeri (Boulenger, 1899) and Boulenophrys kuatunensis (Pope, 1929), are two captivating species within the family Megophryidae, which inhabit the mountainous streams in the Eastern of China. In this study, two new complete mitochondrial genomes of B. boettgeri and B. kuatunensis were sequenced, assembled, and annotated using next-generation sequencing. The length of mitochondrial genomes of B. boettgeri and B. kuatunensis was 16,597 and 17,921 bp, respectively, with both containing 13 protein coding genes, 22 tRNA genes, two rRNA genes, and one putative control region. Phylogenetic relationships based on protein-coding mitochondrial genes showed that the two Boulenophrys species formed a cluster with other Boulenophrys species. The two new sequences provide valuable insights into the mitochondrial genomes of these two species, offering important data for understanding the phylogenetic relationships of the genus Boulenophrys.

The global emergency of antimicrobial resistance has drawn several efforts to evaluate new drug candidates, such as natural defensive biomolecules. Ocellatins are a group of antimicrobial peptides found in anurans of the Leptodactylidae family. This work investigated the presence of antimicrobial peptides in the skin secretion of Leptodactylus vastus from the Brazilian northeast. The secretion was fractionated by RP-HPLC, and the fractions were screened for antibacterial activity. A peptide isolated from the most active fraction was characterized for primary structure and evaluated for antibacterial activity, cytotoxicity to murine melanoma cells (B16-F10), and hemolytic activity. The RP-HPLC profile displayed 26 fractions, with fraction 25 being the most active. One of the two peptides present in this fraction had the primary structure determined, belonging to the group of ocellatins. Since it was not identical to other ocellatins previously reported, it was named ocellatin-VT. This peptide especially inhibited Gram-negative bacteria growth, with the highest activity against Acinetobacter baumannii and Escherichia coli (growth inhibition was higher than 95% at 8 and 16 µM, respectively). Ocellatin-VT was weakly cytotoxic to B16-F10 cells and showed low hemolytic activity. In conclusion, a new ocellatin was isolated from L. vastus skin secretion that was active against non-resistant and multidrug-resistant bacteria.

In anurans communities, vocalizations play a fundamental role in social interactions, being the most important behavioral modality of communication. Therefore, the description of acoustic signals is indispensable for understanding aspects of their evolutionary history. The Cycloramphus genus consists of 30 species allocated into five groups, of which only 19 have the vocalization described. Cycloramphus lithomimeticus is a small-sized frog belonging to the C. granulosus group. This poorly known species is associated with rock surfaces near waterfalls in Atlantic montane forests, restricted to the state of Rio de Janeiro, southeastern Brazil. Currently, it’s classified as Near Threatened species category of IUCN and many aspects of its natural history remain unknown. Herein, we describe the advertisement call of C. lithomimeticus extending its known geographical distribution and providing additional data on the natural history of the species. We recorded and analyzed 44 calls from 10 males of C. lithomimeticus. The advertisement call of C. lithomimeticus consists of a single pulsed note with 0.3–0.8 sec of duration, emitted sporadically, with an interval between calls of 27.5–226.3 sec, composed by 7–17 pulses emitted at a rate of 18–26/sec, with a peak frequency of 2062.5–3000 Hz. After defining the correspondence between structures for systematic purposes, we made a comparative analysis determined by establishing homology connections with other species of the genus. According to our dominant frequency evolutionary reconstruction, an evolutionary increase in frequency mainly occurred in the C. lithomimeticus species lineage from an ancestral dominant frequency of 1500 Hz of the clade with C. eleutherodactylus species group, C. granulosus species group, and C. fuliginosus species group. This study contributes to our knowledge about the biology of C. lithomimeticus, and our results provide basic data for further acoustic, taxonomic and ecological studies in the genus Cycloramphus. [ABSTRACT FROM AUTHOR]

Animals constantly need to evaluate available external and internal information to make appropriate decisions. Identifying, assessing, and acting on relevant cues in contexts such as mate choice, intra-sexual competition, and parental care is particularly important for optimizing individual reproductive success. Several factors can influence decision-making, such as external environmental cues and the animal's own internal state, yet, we have limited knowledge on how animals integrate available information. Here, we used an entire island population (57 males, 53 females, and 1,109 tadpoles) of the neotropical brilliant-thighed poison frog Allobates femoralis to investigate how 2 factors (olfactory cues and personality traits) influence the ability of males to find and use new resources for tadpole deposition. We experimentally manipulated the location of tadpole deposition sites and their associated olfactory cues, and repeatedly measured exploration and boldness in adult males. We further reconstructed tadpole deposition choices via inferred parent–offspring relationships of adult frogs and tadpoles deposited in our experimental pools using molecular parentage analysis. We found that the discovery and use of new rearing sites were heavily influenced by olfactory cues; however, we did not find an effect of the measured behavioral traits on resource discovery and use. We conclude that in highly dynamic environments such as tropical rainforests, reliable external cues likely take priority over personality traits, helping individuals to discover and make use of reproductive resources. [ABSTRACT FROM AUTHOR]

Establishment of extant terrestrial vertebrate faunas in North America was influenced by a set of factors associated with temporal changes in climate and ecology that operated at different geographic scales. While the biogeography of extant taxa can be inferred from phylogenies, these omit lineages that have gone regionally extinct and for which the only direct evidence is the fossil record. A comprehensive study of anurans from the Late Oligocene of Florida reveals an abundance of fossils referred to Eleutherodactylus. Time-calibrated molecular phylogenies have suggested that this genus originated in the Caribbean in the Early Oligocene and then colonized Central America in the Middle Miocene. Here, we describe the first records of pre-Quaternary fossils referred to Eleutherodactylus from Florida. Results from analysis of inter- and intraspecific variation in anatomy, size, and shape of isolated bones of fossil and extant species suggest that the fossils represent adult individuals with an estimated body size (snout–urostyle length) of 16.8–29.8 mm. We show that Eleutherodactylus was established by the Late Oligocene in North America well before colonizing Central America in the Miocene. We provide, for the first time, evidence of dispersal of amphibians from the Caribbean into North America during the Late Oligocene. [ABSTRACT FROM AUTHOR]

Advertisement calls are the main communication form of anurans, and other individuals can use it to evaluate several aspects of the calling individual. In this context, environmental disturbances, such as traffic noise, can potentially affect this recognition. Therefore, this study aims to evaluate the response of Aplastodiscus leucopygius to traffic noise in a fragment of Atlantic Forest within the city of São Paulo. The experimentation consisted of recording the calling individual previously, during and after an exposure to urban noise. After that, individuals were measured to evaluate the Scaled Mass Index (SMI), and individual and environmental temperatures were taken. Also, considering that individuals of this species present harmonic shifting, we tried to evaluate which factors (individual, acoustic, or environmental) are associated with this phenomenon. We observed that the individuals showed an increase in call activity after exposure to traffic noise, but none of the evaluated aspects here could explain the harmonic shifting in their calls. Considering that this increasing on call activity also means an increasing of individual's expense of energy, traffic noise is potentially harmful to the communication of A. leucopygius and, consequently, to its permanence in the site. [ABSTRACT FROM AUTHOR]

Anthropogenic activity and urbanization subject the diversity and distribution of amphibians to constant change. This study aims to reveal the impact of increasing urbanization pressure on amphibian diversity, density, and distribution in Istanbul, a megacity. I researched amphibian species' presence and dispersal in and around the wetlands of Istanbul, spanning urban, semi-urban, and non-urban areas. I conducted surveys in 2016 and 2017 at 396 sites and found seven species (four families) of amphibians at 151 stations. Anurans occurred at 38.13% of sites, and newts at 8.6%. The alpha diversity of semi-urban regions was higher than in urban and non-urban areas of Istanbul. Nonmetric multidimensional scaling (NMDS) analysis of relative abundances of amphibian species at the three site types showed significant differences. Compared to the distribution of each species reported in the literature, I found that distributions have spread to the west, east, and north of the province. Several species occurred in semi-urban wetlands due to the pressure of urbanization, which causes extirpations or declines to low abundance, making their detection unlikely in urban areas. [ABSTRACT FROM AUTHOR]

Nonvisual opsins are transmembrane proteins expressed in the eyes and other tissues of many animals. When paired with a light-sensitive chromophore, nonvisual opsins form photopigments involved in various nonvisual, light-detection functions including circadian rhythm regulation, light-seeking behaviors, and seasonal responses. Here, we investigate the molecular evolution of nonvisual opsin genes in anuran amphibians (frogs and toads). We test several evolutionary hypotheses including the predicted loss of nonvisual opsins due to nocturnal ancestry and potential functional differences in nonvisual opsins resulting from environmental light variation across diverse anuran ecologies. Using whole-eye transcriptomes of 81 species, combined with genomes, multitissue transcriptomes, and independently annotated genes from an additional 21 species, we identify which nonvisual opsins are present in anuran genomes and those that are also expressed in the eyes, compare selective constraint among genes, and test for potential adaptive evolution by comparing selection between discrete ecological classes. At the genomic level, we recovered all 18 ancestral vertebrate nonvisual opsins, indicating that anurans demonstrate the lowest documented amount of opsin gene loss among ancestrally nocturnal tetrapods. We consistently found expression of 14 nonvisual opsins in anuran eyes and detected positive selection in a subset of these genes. We also found shifts in selective constraint acting on nonvisual opsins in frogs with differing activity periods, habitats, distributions, life histories, and pupil shapes, which may reflect functional adaptation. Although many nonvisual opsins remain poorly understood, these findings provide insight into the diversity and evolution of these genes across anurans, filling an important gap in our understanding of vertebrate opsins and setting the stage for future research on their functional evolution across taxa. [ABSTRACT FROM AUTHOR]

This paper is an inventory of amphibians and reptiles occurring in Kakoi Reserve Forest of Lakhimpur District of Assam, North-east India and is based on the survey done in 2017–2018 (from the month of January 2017–January 2018). A total of 34 species of herpetofauna comprising of 12 species of amphibians and 22 species of reptiles have been recorded from the study area. All the recorded species of amphibians are of the order Anura and are composed of 4 families and 7 genera. Among reptiles, we recorded 4 families, 5 genera, and 9 species of lizards; 4 families, 10 genera, and 12 species of snakes, and a single species of turtle. [ABSTRACT FROM AUTHOR]

The behavioural responses of predator-naïve (laboratory-born), predator-experienced (laboratory-born but with short-term experience with predators), and wild-caught (with long-term experience with predators in natural settings) tadpoles of Sphaerotheca breviceps to carnivorous predatory tadpoles of Hoplobatrachus tigerinus was studied in the laboratory. The predator's stimulus solution (kairomones) was used to simulate predation threat. All S. breviceps tadpoles (i.e., predatornaïve, predator-experienced and wild-caught) exhibited behavioural antipredator responses, i.e., reduced swimming activity and time spent swimming, and had a higher burst speed in response to water-borne kairomonal cues of predators. Wildcaught tadpoles showed stronger responses than predator-naïve and predator-experienced tadpoles and the latter exhibited stronger responses than predator-naïve tadpoles. Our study thus suggests that antipredator behaviour in these tadpoles is basically innate. Furthermore, the enhanced antipredator behaviour of wild-caught tadpoles indicates that learning is involved. [ABSTRACT FROM AUTHOR]

Body and limb size are associated with many aspects of the biology of animals. Geographic variation in morphological traits has often been investigated through ecogeographical rules. Bergmann's rule posits an inverse relationship between body size and temperature in homeotherms, while Allen's rule posits that endothermic animals inhabiting colder climates have relatively shorter protruding parts (e.g., limbs) in comparison to populations from warmer climates. However, the applicability and validity of these rules in poikilotherms are currently contentious. In this study, we aimed to test predictions of Bergmann's and Allen's rules in populations of the Neotropical frog Boana platanera. We analysed 142 adult male museum specimens from 17 localities along a mountain range in western Venezuela. We obtained six external morphological measurements and assessed the correlation of body size and limb size with temperature data for each locality. Our results were contrary to the expectations but consistent with previous studies. All this together indicates that exceptions to the Bergmann's and Allen's rules are frequent and idiosyncratic in anurans. We discuss alternative hypotheses that could explain geographic variation of body and limb size in future studies. [ABSTRACT FROM AUTHOR]

Sky Islands present unique landscapes for organismal evolution because they comprise high mountain peaks separated by low valleys with vastly different environmental conditions. The Espinhaço Mountain Range in eastern Brazil is formed of groups of Sky Islands in the states of Minas Gerais and Bahia. Several phylogeographic studies have discovered strong genetic structure among populations of organisms occupying the campo rupestre (rupestrian fields) in the mountains of the Espinhaço. In this study, we aimed to test the hypothesis of spatio-temporal structuring of populations of Scinax curicica in the campo rupestre of the Espinhaço. We recovered three lineages of S. curicica : one lineage occurs in the north portion of the Espinhaço (North Lineage) in an area called Chapada Diamantina, and other two occur in the south portion of the Espinhaço (South 1 and South 2 Lineages) in Minas Gerais. All three lineages showed stable population sizes through time, probably due to the climatic stability of mountaintop areas, which was supported by ecological niche modelling. [ABSTRACT FROM AUTHOR]

The Alliance of Genome Resources (Alliance) is an extensible coalition of knowledgebases focused on the genetics and genomics of intensively studied model organisms. The Alliance is organized as individual knowledge centers with strong connections to their research communities and a centralized software infrastructure, discussed here. Model organisms currently represented in the Alliance are budding yeast, Caenorhabditis elegans , Drosophila , zebrafish, frog, laboratory mouse, laboratory rat, and the Gene Ontology Consortium. The project is in a rapid development phase to harmonize knowledge, store it, analyze it, and present it to the community through a web portal, direct downloads, and application programming interfaces (APIs). Here, we focus on developments over the last 2 years. Specifically, we added and enhanced tools for browsing the genome (JBrowse), downloading sequences, mining complex data (AllianceMine), visualizing pathways, full-text searching of the literature (Textpresso), and sequence similarity searching (SequenceServer). We enhanced existing interactive data tables and added an interactive table of paralogs to complement our representation of orthology. To support individual model organism communities, we implemented species-specific "landing pages" and will add disease-specific portals soon; in addition, we support a common community forum implemented in Discourse software. We describe our progress toward a central persistent database to support curation, the data modeling that underpins harmonization, and progress toward a state-of-the-art literature curation system with integrated artificial intelligence and machine learning (AI/ML). [ABSTRACT FROM AUTHOR]

Introduction: The tribes Cophomantini, Scinaxini, and Dendropsophini are anurans that belong to Hylidae, with wide distribution in tropical and subtropical regions around the world. The taxonomy and systematics of this family remain in a state of ongoing revision. Previous cytogenetic analyses of genera Boana, Bokermannohyla, Ololygon, Scinax, and Dendropsophus described some karyotypic characters such as conventional staining, C-banding and NORs, and FISH with specific probes. Methods: This study describes for the first time the karyotypes of four species: Bokermannohyla ibitipoca, Ololygon luizotavioi, Dendropsophus bipunctatus, and Dendropsophus ruschii. Furthermore, we map CA(15) and CAT(10) microsatellite sites for the aforementioned species and six more species from the same genera for insight into the chromosomal evolution within the subfamily Hyalinae. Results:B. ibitipoca and O. luizotavioi had 2n = 24 and karyotypic formulas 18m + 4sm + 2st and 8m + 12sm + 4st, while D. bipunctatus and D. ruschii showed 2n = 30 and karyotypic formulas 12m + 12sm + 4st + 2t and 10m + 10sm + 6st + 4t, respectively. The diploid numbers and karyotypic formulas revealed here follow the previously reported trend for Hylidae, except B. ibitipoca has a particularity of eight metacentric chromosomes, more than what is commonly found in species of this genus. The microsatellites probes CA(15) and CAT(10) had markings accumulated in blocks in the centromeric, pericentromeric, and terminal regions that were more specific for some species, as well as markings scattered along the chromosomes. We present a comprehensive review table of current data on cytogenetics of these genera. Conclusion: Our findings showed that the karyotypes of the hylids studied here majority fit the postulated conserved diploid number (2n = 24) and morphological chromosome patterns, while the mapping of the microsatellites enabled us to detect differences between species that share similar chromosomal morphologies. [ABSTRACT FROM AUTHOR]