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Invasive species threaten biodiversity globally. Amphibians are one of the most threatened vertebrate taxa and are particularly sensitive to invasive species, including other amphibians. African clawed frogs (Xenopus laevis) are native to Southern Africa but have subsequently become invasive on multiple continents-including multiple parts of North America-due to releases from the pet and biomedical trades. Despite their prevalence as a global invader, the impact of X. laevis remains understudied. This includes the Pacific Northwest of the USA, which now hosts multiple expanding X. laevis populations. For many amphibians, chemical cues communicate important information, including the presence of predators. Here, we tested the role chemical cues may play in mediating interactions between feral X. laevis and native amphibians in the Pacific Northwest. We tested whether native red-legged frog (Rana aurora) tadpoles display an antipredator response to non-native frog (X. laevis) or native newt (rough-skinned newts, Taricha granulosa) predator chemical stimuli. We found that R. aurora tadpoles exhibited pronounced anti-predator responses when exposed to chemical cues from T. granulosa but did not display anti-predator response to invasive X. laevis chemical cues. We also began experimentally testing whether T. granulosa-which produce a powerful neurotoxin tetrodotoxin (TTX)-may elicit an anti-predator response in X. laevis, that could serve to deter co-occupation. However, our short-duration experiments found that X. laevis were attracted to newt chemical stimuli rather than deterred. Our findings show that X. laevis likely poses a threat to native amphibians, and that these native species may also be particularly vulnerable to this invasive predator, compared to native predators, because toxic native newts may not limit X. laevis invasions. Our research provides some of the first indications that native Pacific Northwest species may be threatened by feral X. laevis and provides a foundation for future experiments testing potential management techniques for X. laevis.

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]

Haematological and genotoxicological parameters of the Levant green frog Pelophylax bedriagae (Camerano, 1882) and the Western Caspian turtle Mauremys rivulata (Valenciennes, 1833) were studied. These species inhabited two sites with differing water quality in the Sarıçay Stream passing through the city centre of Çanakkale, Türkiye. We examined whether the two species were affected by the water quality classes identified based on physical and chemical properties of the water. Statistically significant differences were found between the two sites in terms of the frequencies of micronucleus, lobbed, notched, kidney-shaped and blebbed nuclei, as well as total nuclear abnormality in Pelophylax bedriagae. Moreover, a higher rate of nuclear abnormalities was observed at the more polluted site, classified as water quality class IV. Statistically significant differences were observed in the haematocrit value, percentages of lymphocytes, eosinophils, heterophils and basophils, erythrocyte width and frequencies of lobbed and kidney-shaped nuclei as well as the heterophil/lymphocyte ratio, often used as a stress indicator, in Mauremys rivulata. In this species, it was determined that parameters other than lymphocyte and eosinophil percentages were higher in specimens from the more polluted site. [ABSTRACT FROM AUTHOR]

Despite amphibians having the least number of families in comparison with other vertebrate classes, the digenean parasites within these host species are largely predominant. To date, no investigation has been conducted on the digenean fauna of frogs in western Iran. The helminths occurrence and morphological description of this study were analyzed for the first time. A total of 54 Levant water frogs, Pelophylax bedriagae, (n = 53), and a long-legged wood frog, Rana macronemis, (n = 1) were examined. Frogs harbor in total four digenean parasites. Three taxa were characterized based on morphological features as Gorgodera cf. asiatica, G. varsoniensis, and Pleurogenoides sp. within P. bedriagae, while Haematoloechus sp. was only found in R. macronemis. Pleurogenoides sp. exhibited a moderate prevalence (23%) and intensity (7.3 ± 6.3). Gorgodera cf. asictica can be distinguished from congeners based on the body and sucker size, the ovary and testes shape, and in G. varsoviensis by having lobulated caeca and transversely elongated testes. In addition, Pleurogenoides sp. mainly differs from all its congeners by the form of its body, genital apparatus shape and Y-shaped excretory vesicles. With regard to helminths in amphibians, the existing body of literature is extensive and complex. To accurately determine the species boundaries, both morphological and molecular data are needed. We report two new records of these parasites from the region. [ABSTRACT FROM AUTHOR]

This article provides the first data on amphibian diversity in the Yoko Forest Reserve, located in the Democratic Republic of the Congo. During twenty-four field sampling campaigns organized over a period of twelve months, amphibians were collected from nocturnal surveys supported by three techniques: visual spotting using a headlamp, systematic searching of habitats and acoustic hearing of vocalizations. A total of 5707 amphibians in 10 families, 17 genera and 33 species were recorded throughout the study area. The Hyperoliidae and Arthroleptidae families were the most diverse, with Amnirana albolabris (Ranidae) the most abundant species, followed by Phrynobatrachus auritus (Phrynobatrachidae). By contrast, Afrixalus quadrivittatus, A. equatorialis, Arthroleptis tuberosus, A. variabilis, Cryptothylax greshoffi, Hyperolius langi, H. ocellatus, H. parallelus, Hyperolius sp., Hoplobatrachus occipitalis, Kassina maculosa, Leptopelis calcaratus, Nectophryne batesii, Phrynobatrachus perpalmatus, Sclerophrys gracilipes and S. gutturalis were less frequent. For the first time, Amietia nutti and Kassina maculosa have been reported in Congolese forests. Amphibian species known from the YFRE are widely distributed in Central African forests, and particularly in the Democratic Republic of the Congo, where A. equatorialis, H. langi, H. parallelus and Ptychadena christyi are endemic. [ABSTRACT FROM AUTHOR]

The Pelophylax genus comprises two main hybridogenetic systems resulting from hybridization between Pelophylax ridibundus and other species: the P. lessonae-esculentus (LE) system and the P. perezi-grafi (PG) system, whose distribution ranges lie partly (LE) or entirely (PG) outside the natural distribution of P. ridibundus. The introductions and subsequent expansions of P. ridibundus in many areas naturally inhabited by these hybridogenetic systems have led to their decrease or local extinction. One of the major impediments to efficient population surveys and conservation measures for these systems is the difficulties of reliable species identification due to their similar morphology and poorly documented vocalizations, especially for the PG system. Our aim in this work was to design a reliable method of acoustic identification to distinguish the taxa composing the hybridogenetic systems from P. ridibundus and to assess the possibility of separating the PG and LE systems by their vocalizations. Our acoustic identification methods proved highly accurate to separate the PG and LE systems from P. ridibundus but only a fraction of the PG and LE calls can be identified. [ABSTRACT FROM AUTHOR]

Simple Summary: This study aimed to investigate the function of the nuptial pad-secreted pheromone in anurans. By conducting transcriptome sequencing of the nuptial pads of the Yunnan pond frog, we obtained transcripts of protein pheromones that were highly expressed in the nuptial pads during the breeding season. These pheromones were homologous to the common frog amplexins and the plethodontid modulating factor (PMF) pheromone of urodeles. By means of recombinant protein expression, we obtained the single subtype of the pheromone and demonstrated its ability to shorten the duration of Yunnan pond frog pairing through behavioral experiments. The results of this study further confirm that urodeles and anurans share the PMF pheromone system. Additionally, this study validates the function of this pheromone in anurans for the first time, confirming that it serves similar functions as in urodeles, shortening the breeding process. Overall, this study provides a paradigm for exploring the function of pheromones in anurans. Chemical communication is an important mode of communication in the courtship and breeding processes of amphibians. In caudates, multiple components of sexual pheromones have been identified and functionally verified. One of these pheromone systems is plethodontid modulating factor (PMF). In anurans, the pheromone called amplexin was found in nuptial pads of ranids and was considered a member of the PMF system, yet its bio-function has not been tested. In this study, we obtained 18 amplexin transcript sequences from nuptial pads of Nidirana pleuraden (Amphibia, Ranidae) by transcriptome sequencing and found that the proteins translated by these transcripts are diversified, hydrophilic, and relatively stable. We also acquired a N. pleuraden amplexin isoform with the highest expression level in the transcriptome analysis through the prokaryotic expression system. Using two different animal behavioral experimental settings, we have tested the bio-function of the recombinant PMF protein (rPMF) in N. pleuraden's reproduction and found that the rPMF does not attract females but shortens the duration of amplexus significantly. This is the first study to verify the function of the PMF pheromone in Anura, indicating the pervasiveness of chemical communication during breeding in amphibians. [ABSTRACT FROM AUTHOR]

Restriction-site-associated DNA sequencing (RADseq) has become an accessible way to obtain genome-wide data in the form of single-nucleotide polymorphisms (SNPs) for phylogenetic inference. Nonetheless, how differences in RADseq methods influence phylogenetic estimation is poorly understood because most comparisons have largely relied on conceptual predictions rather than empirical tests. We examine how differences in ddRAD and 2bRAD data influence phylogenetic estimation in two non-model frog groups. We compare the impact of method choice on phylogenetic information, missing data, and allelic dropout, considering different sequencing depths. Given that researchers must balance input (funding, time) with output (amount and quality of data), we also provide comparisons of laboratory effort, computational time, monetary costs, and the repeatability of library preparation and sequencing. Both 2bRAD and ddRAD methods estimated well-supported trees, even at low sequencing depths, and had comparable amounts of missing data, patterns of allelic dropout, and phylogenetic signal. Compared to ddRAD, 2bRAD produced more repeatable datasets, had simpler laboratory protocols, and had an overall faster bioinformatics assembly. However, many fewer parsimony-informative sites per SNP were obtained from 2bRAD data when using native pipelines, highlighting a need for further investigation into the effects of each pipeline on resulting datasets. Our study underscores the importance of comparing RADseq methods, such as expected results and theoretical performance using empirical datasets, before undertaking costly experiments.

Many native insects have evolved defenses against native predators. However, their defenses may not protect them from non-native predators due to a limited shared history. The American bullfrog, Aquarana catesbeiana (Anura: Ranidae), which has been intentionally introduced to many countries, is believed to impact native aquatic animals through direct predation. Adults of whirligig beetles (Coleoptera: Gyrinidae), known for swimming and foraging on the water surface of ponds and streams, reportedly possess chemical defenses against aquatic predators, such as fish. Although whirligig beetles potentially encounter both bullfrogs and other frogs in ponds and lakes, the effectiveness of their defenses against frogs has been rarely studied. To assess whether whirligig beetles can defend against native and non-native frogs, we observed the behavioral responses of the native pond frog, Pelophylax nigromaculatus (Anura: Ranidae), and the invasive non-native bullfrog, A. catesbeiana, to native whirligig beetles, Gyrinus japonicus and Dineutus orientalis, in Japan. Adults of whirligig beetles were provided to frogs under laboratory conditions. Forty percent of G. japonicus and D.orientalis were rejected by P. nigromaculatus, while all whirligig beetles were easily consumed by A. catesbeiana. Chemical and other secondary defenses ofG. japonicus and D. orientalis were effective for some individuals of P. nigromaculatus but not for any individuals of A. catesbeiana. These results suggest that native whirligig beetles suffer predation by invasive non-native bullfrogs in local ponds and lakes in Japan. [ABSTRACT FROM AUTHOR]

The application of herbicides is one of the leading causes of the decline of amphibians in the world. Atrazine is widely used to control herbaceous weeds in crops. In Mexico, it is not regulated and widely applied. More information regarding the effects of atrazine in aquatic systems and on amphibians in this country is therefore needed. Amphibians have a smooth skin coated with excretions that protect them from harmful environmental influences, yet still facilitates the exchange of gases, ions, and thermoregulation, but is especially susceptible to absorbing toxic substances, including atrazine. A few studies have revealed that atrazine modifies the thickness of the epithelial layer in fish, but there are few studies to that effect in frogs. No studies have investigated whether atrazine exposure affects mucopolysaccharides or glucans, which are essential for hydrating the skin. We hypothesized and found confirmed that the herbicide atrazine reduces the thickness of the dorsal epithelium and promotes a greater presence of mucopolysaccharides in the dorsal epithelium and glands in Lithobates spectabilis. Our findings suggest that this frog is likely more vulnerable to dehydration, ultraviolet radiation, and will suffer impaired wound healing when exposed to atrazine. [ABSTRACT FROM AUTHOR]

The frog genus Odorrana is distributed across east and southeastern Asia. Based on morphological differences and molecular phylogenetics, a new species of the genus occurring from Leigong Mountain in Guizhou Province, China is described. Phylogenetic analyses based on DNA sequences of the mitochondrial 12S rRNA, 16S rRNA, and ND2 genes supported the new species as an independent lineage. The uncorrected genetic distances between the 12S rRNA, 16S rRNA, and ND2 genes between the new species and its closest congener were 5.0%, 4.9%, and 16.3%, respectively. The new species is distinguished from its congeners by a combination of the following characters: body size moderate (SVL 39.1–49.4 mm in males, 49.7 mm in female); head width larger than head length; tympanum distinctly visible; small rounded granules scattered all over dorsal body and limbs; dorsolateral folds absent; heels overlapping when thighs are positioned at right angles to the body; tibiotarsal articulation reaching the level between eye to nostril when leg stretched forward; vocal sacs absent in male and nuptial pads present on the base of finger I. [ABSTRACT FROM AUTHOR]

Studying the distribution of morphologically cryptic animal species is always a very difficult task. Because most marsh frog species (the Pelophylax ridibundus complex) are cryptic, we used molecular markers to identify them. Three marsh frog species (P. ridibundus, P. kurtmuelleri and P. cf. bedriagae) inhabit the northern part of Western Palearctic. We created a database of localities and built models of their modern distribution. These models showed that the most suitable habitats are on the north of the Mediterranean region for P. cf. bedriagae, temperate Europe for P. ridibundus, and the Balkan coastal areas for P. kurtmuelleri. The projection of the modern ecological niches under the late-Quaternary climatic conditions showed that the range of P. kurtmuelleri remained largely unchanged during the period, whereas the ranges of P. cf. bedriagae and especially P. ridibundus changed greatly over time. During the Last Glacial Maximum, the presumed range of P. cf. bedriagae covered a relatively large area in the north of the Mediterranean region and the south of European Russia. Glacial refugia of P. ridibundus were apparently located in the northern Balkans, the northern coast of the Black and Azov seas, and possibly in Western Europe. The northward long-distance post-glacial dispersal of P. ridibundus occurred from refugia in the northeastern Balkans and the Black-Azov seas region. Since the Late Pleistocene, suitable habitats for P. cf. bedriagae in southern Russia began to decline, but local habitats for P. ridibundus become more suitable. Therefore, a mosaic of populations consisting of these both species and their hybrids has now been found here. [ABSTRACT FROM AUTHOR]

The Nagoya Daruma pond frog Pelophylax porosus brevipodus (formerly Rana porosa brevipoda) requires a wet environment year-round, but such habitats have generally been lost due to improved rice paddy drainage such that the frog populations have been decreasing. There have been attempts to create permanent pools in rice paddy areas to help the populations recover, but the basic life history patterns and population dynamics in both environments have not been well studied. We captured frogs in rice paddies and adjacent biotopes. Using capture–mark–recapture data with 816 marked individuals, we compared frog demographics and population structure using a Jolly–Seber POPAN model. Constructed biotopes had conditions favoring long-term persistence. For example, biotopes had larger frogs of both sexes than rice paddies. The ratio of juveniles to adults was lower in biotopes than rice paddies. By contrast, rice paddies were an important habitat for breeding and producing new frogs. The two habitats complemented each other to support the local frog population. Because P. p. brevipodus is now exclusively distributed in rice paddy areas, the creation of permanent pools is a feasible way to improve habitat quality, especially in modernized rice paddy areas with few permanent lentic habitats. [ABSTRACT FROM AUTHOR]

A new species of odorous frog, Odorrana damingshanensis sp. nov., was found at the Damingshan National Nature Reserve in Guangxi, China. This species can be distinguished from its congeners by a combination of the following characters: medium body size (SVL 52.3–54.8 mm in males and 74.8–81.2 mm in females), sawtooth spinules on the upper lip, obtusely rounded snout that extends beyond the lower margin, distinct dorsolateral folds, horny tubercles on the rear of the back, presence of outer metatarsal tubercles, dilated nuptial pad with velvety spinules, distinct maxillary gland with tiny spines, and external lateral vocal sac. Through analysis of the 16S mitochondria gene, the new species is closely related to O. nasica and O. yentuensis, but the genetic divergence between the new species and the latter exceeds 7% (uncorrected p-distance). Currently, the new species is only known from its original discovery site. Furthermore, a discussion on the taxonomy of Odorrana (Bamburana) was conducted, identifying seven species within the subgenus Odorrana (Bamburana). [ABSTRACT FROM AUTHOR]

The Torrent frogs of the genus Amolops are widely distributed in Nepal and northern India eastwards to southern China and southwards to Malaysia. The genus currently contains 84 species. Previous studies indicated underestimated species diversity in the genus. In the context, a new species occurring from the mountains in the northwestern Guizhou Province, China is found and described based on morphological comparisons and molecular phylogenetic analyses, Amolops dafangensis sp. nov. Phylogenetic analyses based on DNA sequences of the mitochondrial 16S rRNA and COI genes supported the new species as an independent lineage. The uncorrected genetic distances between the 16S rRNA and COI genes in the new species and its closest congener were 0.7% and 2.6%, respectively, which are higher than or at the same level as those among many pairs of congeners. Morphologically, the new species can be distinguished from its congeners by a combination of the following characters: body size moderate (SVL 43.2-46.8 mm in males); head length larger than head width slightly; tympanum distinct, oval; vocal sacs absent; vomerine teeth present; dorsolateral folds weak formed by series of glands; nuptial pads present on the base of finger I; heels overlapping when thighs are positioned at right angles to the body; tibiotarsal articulation reaching the level far beyond the tip of the snout when leg stretched forward. [ABSTRACT FROM AUTHOR]

The assessment of the health and protection of anuran amphibian populations in biotopes damaged by anthropogenic activity is today a priority and a global problem. The aim of this study is to determine the individual physical fitness of Pelophylax ridibundus individuals inhabiting a polluted area in Southern Bulgaria by calculating the scaled mass index (SMI) of frogs. We used frogs inhabiting a less disrupted habitat (less disturbed site) in order to make a comparison. Our working hypothesis was based upon the assumption that the two populations were expected to show differences in the values of the calculated scaled mass indices. That would allow us to assess how anthropogenic stress affects the individual body condition of frogs inhabiting a polluted area. A two-way ANOVA analysis revealed that there was a statistically significant interaction between the effects of site and sex on SMI. The simple main effects analysis showed that the site of origin alone has had a significant effect on SMI. In general, lower SMI values were indicative of deteriorated body fitness and suggested unfavorable environmental conditions. We found during this study that SMI can be discussed as a more accurate sex-independent discriminative marker for the habitat than the original unscaled SVL and BW parameters. [ABSTRACT FROM AUTHOR]

Environmental niche models are useful tools for generating hypotheses for the distribution of species and informing conservation planning, especially at the edge of species' ranges and for those with limited data. Here we report on the recent documentation of four species of amphibian (Hylarana latouchii, Odorrana tianmuii, Polypedates braueri, and Zhangixalus dennysi) and one reptile (Protobothrops mucrosquamatus) with few or no previous geolocated records from Jiangsu, China. We combined our opportunistic field sampling data from Jiangsu, which is at the edge of each of these species' ranges, with publicly available occurrence records and climatic data to generate environmental niche models for these five species using Maxent. All models showed good model performance with AUC values ranging from 0.899 to 0.983. Additional potentially suitable areas within southern Jiangsu were predicted for the four amphibian species, although the significant anthropogenic habitat modifications in the province may limit their contemporary distributions. For all five species, the climatic variable that contributed most to the model was the precipitation of the driest month (Bio 14), indicating they are limited by moisture availability. Our study adds new information about the climatic preferences of these five species and highlights the value of complementing environmental niche modeling with field surveys for robust inferences and conservation planning, particularly at the edge of species' ranges. [ABSTRACT FROM AUTHOR]

One specimen of frog was collected from Mohan Town, Mengla County, Xishuangbanna Prefecture, Yunnan Province, China, which is the type locality of Rana bannanica Rao & Yang, 1997, currently considered as a junior synonym of Hylarana milleti (Smith, 1921). This specimen well agrees with the original description of R. bannanica. In regard to morphology, R. bannanica and H. milleti are, indeed, very similar, but can still be distinguished from each other. Phylogenetic analysis, based on mitochondrial gene sequences, showed that this specimen and H. milleti are different species. Hence, we remove R. bannanica from the synonymy of H. milleti. [ABSTRACT FROM AUTHOR]

We present the results of an in situ study of a set of blood parameters in adult marsh frogs (Pelophylax ridibundus (Pallas 1771) from populations inhabiting the largest system of rice fields in Bulgaria, the Tsalapitsa rice fields (TRF), under chronic stress conditions. This study was conducted in spring 2022 to assess the health status of TRF frogs compared to that of frogs occupying a reference site (RS). Furthermore, this study also compared the results obtained for the TRF population with those obtained in a study conducted at the exact same location with P. ridibundus individuals in 2013 (Zhelev et al. 2018). This comparison highlights the potential effects of persistent use of agrochemicals (pesticides and fertilizers) on the marsh frogs of later generations. Our results suggest that the general health of marsh frogs in the polluted site (PS) in southern Bulgaria has severely deteriorated. Frogs of both sexes were anemic with weakened immune systems compared to those living in the RS. The long-term use of agrochemicals in the PS affected males to a greater extent than it did females. Statistically significant hypochromia was observed in males, combined with general leukopenia, neutrophilia, lymphopenia, monocytosis, eosinophilia, and higher neutrophil/lymphocyte (N/L) ratios. [ABSTRACT FROM AUTHOR]

Abstract—The aim of this work was to estimate the state of the populations of tailless amphibians in the anthropogenic territory according to a complex of indices of immune homeostasis of the organism. The marsh frog Pelophylax ridibundus (Pallas, 1771) and the pool frog P. lessonae (Camerano, 1882) from natural populations of water objects from the city of Nizhny Novgorod were used in the work. The priority chemical pollutants of the reservoirs were determined using a spectrophotometry method. The species identification was performed using a multiplex PCR test system. The results of identification were verified by sequencing of the mitochondrial ND2 gene and a fragment of the nuclear SAI gene. The number of erythrocytes, leukocytes, leukocyte profile, and the level of immune complexes were determined in all individuals collected. Exceeding the water quality standard by the content of heavy metals was determined for fishery reservoirs in all water objects. Molecular genetic diagnostics demonstrated the presence of both "pure" P. ridibundus and individuals with introgressive mtDNA of the Anatolian form of the marsh frog (P. cf. bedriagae) in the sample of marsh frogs. In the sample of pool frogs, all individuals studied had only species-specific markers of mt- and nDNA markers of P. lessonae. The marsh frogs differed from the pool frogs by an increased content of erythrocytes, neutrophils, basophils, and small immune complexes and a decreased content of lymphocytes. The detected changes in the immunohematological indices of green frogs were caused by the complex genotoxic effect of the pollutants of water objects. A decrease in the lymphocyte/eosinophil ratio index with an increase in the concentration of nitrites, an increase in the activity of humoral immune responses under conditions of the pollution of water environment with sulfates, an increase in the portion of immature leukocyte cells (myelocytes) in the blood of the frogs with an increase in the concentration of manganese and nitrates in the water were demonstrated. Under conditions of environmental stress (determined by the level of water pollution), the regulatory systems of the frog blood reflected a stress-induced response, which was more pronounced in the organism of marsh frogs as compared to the pool frogs. [ABSTRACT FROM AUTHOR]

Abstract—The time series of the dates of the end of wintering and the beginning of spawning migrations of the marsh frog in the valley of the middle reaches of the Medveditsa River (Don basin, Saratov oblast) has been analyzed. It was established that in the period from 1892 to 2021, the phenological norm of this phase of the annual cycle shifted to earlier dates by an average of six days (from May 2 to April 26) under conditions of climate warming. Possible consequences of this transformation of the spring phenology of anurans in connection with the established changes are discussed. Continued monitoring of phenological changes in the spring phase of the annual cycle is required to forecast the population dynamics of this anuran species and the scientific basis for their conservation. [ABSTRACT FROM AUTHOR]

Terentiev's frog (Pelophylax terentievi) is one of the least studied representatives of the genus. The results of studying the age structure and growth of this species based on skeletochronology, as well as the results of fertility assessment, are presented for the first time. Altogether, 36 specimens from the vicinity of Shahritus, Khatlon region, southern Tajikistan were studied. In all individuals, lines of arrested growth were found in the cross sections of bones. The age averaged 3.5 ± 0.98 years in females compared to 4.1 ± 1.38 years in males, and the maximum age was five and six years, respectively. Adult females and males did not differ in body length, but the former were able to reach a longer body during their lifetime (SVLmax is 99.16 mm for females and 62.84 mm for males), while their growth coefficient (k) was significantly lower than that of males (0.182 and 0.549, respectively). Females were characterized by lower rates of estimated survival (S is 0.72 in females and 0.77 in males) and life expectancy (ESP is 4.11 years in females and 4.86 years in males). Frogs reach sexual maturity at the age of three or four years, and their absolute fertility is 138–3317 eggs per female. [ABSTRACT FROM AUTHOR]

Geomorphological changes have played a central role in species diversification by promoting vicariance through barriers that reduce gene flow. However, niche evolution leading to local adaptations to new environments may also drive speciation, regardless of the presence of geographical barriers. Here, we assessed the role of geological changes and climatic niche evolution in the diversification of true frogs of the Rana palmipes species group (Ranidae) in Central and South America. We investigated if the evolutionary history of species was shaped by vicariance and ecological niche conservatism, founder events followed by niche divergence or both by estimating ancestral areas. Then, we used a phyloclimatic analysis to quantify niche overlap and tested for niche conservatism between species. We found a pattern of both vicariance and successive founder events from north to south, with lineages reaching newly formed areas during the formation of Central America throughout the Miocene and Pliocene, and at least two dispersal events into South America. Species presented low overlaps in climatic niche and phyloclimatic analysis did not recover a phylogenetic signal. Profiles of niche occupancy diverging over time and high values of disparity between clades indicate niche divergence during the evolutionary history of species. Our results indicate an interplay between niche evolution and geological changes acting on Rana palmipes species group diversification. Speciation events were probably driven by vicariance and ecological speciation after successive dispersal events, while species occupied new areas available during the uplift of Talamanca and Andes Mountain ranges. [ABSTRACT FROM AUTHOR]

Using skeletochronology, we assessed the relationships of age and body size (SVL) in individuals from a population of the agile frog Rana dalmatina near the village of Özyurt, North-western Türkiye. The mean age and SVL of adult frogs were 4.50 ± 0.38 years and 61.54 ± 1.31 mm (6.46 ± 0.33 years and 67.86 ± 1.00 mm in females and 3.00 ± 2.71 years and 56.70 ± 1.26 mm in males, respectively). Intersexual differences in body size were female-biased (SSD = 0.196) while the age ranged between 4-8 years in females and 2-6 years in males. There was a positive correlation between body size and age (i.e., larger frogs were older) in both female and male individuals of this species. [ABSTRACT FROM AUTHOR]

Most of the anuran tadpoles spend their early phase of life in aquatic medium. In such system, they respond to a wide variety of stimuli (e.g., tactile, chemical and visual cues) and exhibit appropriate behavioural responses. The ability to detection food and predator was studied in the tadpoles of the bicolored frog, Clinotarsus curtipes in the laboratory by using a rectangular glass test tank with end compartments (stimulus zones) providing exclusively visual and/or chemical food (boiled spinach) or predator (Laccotrephes sp.) cues. A test tadpole, C. curtipes (either starved or fed; Gosner stage 25) was held at the centre of the test tank for 5 min (acclimation) to perceive visual and/or chemical food or predator cues. Then it was released from the centre of the test tank and allowed to associate or stay away from the caged stimulus subjects (food or predator), which were placed at one end of the test tank either in a glass beaker (visual cues) or in a mesh cage wrapped with cheese cloth (chemical cues) for a period of 10 min. The test tadpoles were unable to detect both food and predator through visual cues. They spent almost an equal amount of time in the zone housing food or predator in a glass beaker or opposite zone, which was kept empty. However, they detected both food and predator solely through chemical cues. In tests with chemical food cues, they spent a significantly higher period of time (70.42% of total time) near chemical food cues rather than empty or visual food cues. In contrast, in tests with chemical predator cues, they spent the majority of their time (69.32% of total time) away from the chemical predator cues. The findings thus show that C. curtipes tadpoles detect both food and predator solely through chemical cues rather than visual cues. [ABSTRACT FROM AUTHOR]

Frogs in the family Ranidae are diverse in Asia and are thought to have dispersed to the Sahul Shelf approximately 10 million years ago, where they radiated into more than a dozen species. Ranid species in the intervening oceanic islands of Wallacea, such as Hylarana florensis and H. elberti from the Lesser Sundas and H. moluccana from eastern Wallacea, are assumed to belong to the subgenus Papurana, yet this has not been confirmed with molecular data. We analyzed mitochondrial DNA of Hylarana species from five islands spanning the reported ranges of H. florensis and H. elberti and compared them to confirmed Papurana species and closely related subgenera within Hylarana. We find that the Lesser Sunda H. florensis and H. elberti form a clade that is sister to the rest of the Australo-Papuan Papurana assemblage. Species delimitation analyses and divergence time estimates suggest that populations of H. florensis on Lombok may be distinct from those on Flores at the species level. Likewise, populations of H. elberti on Sumba and Timor may be distinct from each other and from those on Wetar, tshe type locality of H. elberti. Samples from Babar Island thought to be members of H. elberti in fact belong to the wide-ranging H. daemeli, which occurs in northern Australia, across New Guinea, and on the neighboring island of Tanimbar. These results suggest that the Lesser Sundas may have served as a stepping-stone for colonization of the Sahul Shelf and that species diversity of Papurana frogs is underestimated in the Lesser Sundas.

Here we present a multiplex PCR assay to distinguish three widespread brown frog species, Rana temporaria, R. arvalis and R. amurensis, based on amplified fragment length. The system consists of four primers to the mitochondrial cytochrome c oxidase subunit I gene, with one universal reverse primer and three species-specific forward primers. Therefore, the PCR gives a fragment of a known specific length, which can be identified by electrophoresis in standard agarose gel. The efficiency of the developed assay was confirmed using both pre-identified and unidentified samples. [ABSTRACT FROM AUTHOR]

Studying sexual dimorphism facilitates better understanding of the general intersexual divergence of the same species and gives insights into the impact of selective forces on each sex. The sexual dimorphism in anuran external morphology or limb muscles has been well studied in reproductive context, but less so outside the breeding season. Herein, the intersexual differences in 12 external morphological characteristics, 11 forelimb and 12 hindlimb muscles of Hylarana guentheri during non‐breeding season were investigated. We found that the males possessed significantly greater head width and tympanum diameter, while the females had significantly larger body size and head length; there was no sexual differences in the examined limb muscles, except for the mass of flexor carpi radialis. The larger body size means greater fertility for the females, and the longer head may be related to the allometry and reduce resource competition. For the males, the wider head is likely correlated with prey size and male–male competition, and also, the larger tympanum and heavier flexor carpi radialis probably aid the productive success. This study provides the comprehensive morphological accounts about the sexual differences of H. guentheri during non‐breeding season, which will contribute to clarify the sex‐specific resource allocation and reproductive strategies of anurans. [ABSTRACT FROM AUTHOR]

Background Occidozyga shiwandashaensis was recently discovered from Guangxi Province of China. Hylarana latouchii is a widespread species in southern China, including Hong Kong and Taiwan. Both species are expected to be found in the border areas between Vietnam and China; however, no records of these frogs have been documented from Vietnam so far. New information We record two species of amphibians for the first time from Vietnam, namely Occidozyga shiwandashaensis from Bac Giang Province and Hylarana latouchii from Hai Phong City and Quang Ninh Province in northern Vietnam. Morphologically, the Vietnamese representatives of O. shiwandashanensis resemble the type series from China. The specimens of H. latouchii from Vietnam slightly differ from the type series from China by having a larger size (SVL 48.6-51.7 mm in males, SVL 58.4 mm in the females vs. 36.0-40.0 mm in males, 42.0-53.0 mm in females). Genetic distances between the Vietnamese records and the type specimens of O. shiwandashanensis from China varied from 0 to 1.5% (16S gene). Genetic divergences between the Vietnamese records and H. latouchii from the type locality were 2.0-2.6% (16S gene). In addition, morphological data and natural history notes of the aforementioned species are provided, based on the new records from Vietnam. [ABSTRACT FROM AUTHOR]

Amphibians suffer from large‐scale population declines globally, and emerging infectious diseases contribute heavily to these declines. Amphibian Perkinsea (Pr) is a worldwide anuran pathogen associated with mass mortality events, yet little is known about its epidemiological patterns, especially in comparison to the body of literature on amphibian chytridiomycosis and ranavirosis.Here, we establish Pr infection patterns in natural anuran populations and identify important covariates including climate, host attributes and co‐infection with Ranavirus (Rv).We used quantitative (q)PCR to determine the presence and intensity of Pr and Rv across 1234 individuals sampled throughout central Florida in 2017–2019. We then implemented random forest ensemble learning models to predict infection with both pathogens based on physiological and environmental characteristics.Perkinsea infected 32% of all sampled anurans, and Pr prevalence was significantly elevated in Ranidae frogs, cooler months, metamorphosed individuals and frogs co‐infected with Rv, while Pr intensity was significantly higher in ranid frogs and individuals collected dead. Ranavirus prevalence was 17% overall and was significantly higher in Ranidae frogs, metamorphosed individuals, locations with higher average temperatures, and individuals co‐infected with Pr. Perkinsea prevalence was significantly higher than Rv prevalence across months, regions, life stages and species. Among locations, Pr prevalence was negatively associated with crayfish prevalence and positively associated with relative abundance of microhylids, but Rv prevalence did not associate with any tested co‐variates. Co‐infections were significantly more common than single infections for both pathogens, and we propose that Pr infections may propel Rv infections because seasonal Rv infection peaks followed Pr infection peaks and random forest models found Pr intensity was a leading factor explaining Rv infections.Our study elucidates epidemiological patterns of Pr in Florida and suggests that Pr may be under‐recognized as a cause of anuran declines, especially in the context of pathogen co‐infection. [ABSTRACT FROM AUTHOR]

The mitochondrial genome (mitogenome) possesses several invaluable attributes, including limited recombination, maternal inheritance, a fast evolutionary rate, compact size, and relatively conserved gene arrangement, all of which make it particularly useful for applications in phylogenetic reconstruction, population genetics, and evolutionary research. In this study, we aimed to determine the complete mitogenomes of two morphologically similar Rana species (Rana hanluica and Rana longicrus) using next-generation sequencing. The entire circular mitogenome was successfully identified, with a length of 19,395 bp for R. hanluica and 17,833 bp for R. longicrus. The mitogenomes of both species contained 37 genes, including 13 protein-coding genes (PCGs), two ribosomal RNA genes, 22 transfer RNA genes, and one control region; mitogenome size varied predominantly with the length of the control region. The two synonymous codon usages in 13 PCGs showed that T and A were used more frequently than G and C. The ratios of non-synonymous to synonymous substitutions of all 13 PCGs were <1 in the Rana species, indicating that the PCGs were under purifying selection. Finally, phylogenetic relationship analyses suggested that R. hanluica and R. longicrus were classified in the R. japonica group. Our study provides valuable reference material for the taxonomy of the genus Rana. [ABSTRACT FROM AUTHOR]

Evaluation of changes in the leukogram of adult marsh frogs Pelophylax ridibundus inhabiting the polluted sedimentation lake of the Brikel Thermal Power Station (TPS), southern Bulgaria, as biomarkers for ecological stress is presented. For a comparison, data for frogs inhabiting a less disrupted habitat (reference site, RS) are presented. Leukopenia in the blood of individuals of P. ridibundus inhabiting the sedimentation lake of the Brikel TPS was detected but not in frogs from the reference site. Furthermore, the differential leukocyte count of the affected frogs was characterised by neutrophilia, eosinophilia, monocytosis, basopenia and lymphopenia. The values of the neutrophil-lymphocyte (N/L) ratio of the frogs from the lake of the Brikel TPS were higher than that of the ones inhabiting the RS. These changes in the leukogram are indicators of the exhaustion of the immune system and of activation of the organism's defences in response to stress. The changes in the leukogram are interpreted as caused by the deteriorated water quality in the sedimentation lake as it contained toxicants (reactive water-soluble forms of nitrogen and phosphates) and industrial ash. The results from this study confirm the role of parameter changes in the leukogram of P. ridibundus as diagnostic biomarkers for ecological stress. [ABSTRACT FROM AUTHOR]

Recent molecular analyses cast doubt on the subspecific relationships of Japanese brown frogs Rana tagoi tagoi, R. t. okiensis, and R. t. yakushimensis. Many samples of R. tagoi from three main islands, i.e., Honshu, Shikoku, and Kyushu tend to form a genetic unit with rich variation. On the other hand, R. t. okiensis, R. t. yakushimensis, and some insular samples are clearly isolated from R. t. tagoi and each other. Thus, we propose to treat each subspecies of R. tagoi as full species and describe part of the Goto Islands populations as Rana matsuoi sp. nov. The new species and R. tagoi show a complicated distributional pattern within the Goto Islands but the former is distinguishable from the latter by their smaller male body size, relatively longer limbs, more developed toe webs, nuptial pad formation in breeding male, and advertisement call with repetition of short notes. [ABSTRACT FROM AUTHOR]

A new species of the genus Amolops, Amolops ailao sp. nov., is described from central Yunnan, China. The new species belongs to the A. mantzorum species group. Phylogenetic analyses based on the combination of mitochondrial 16S rRNA, COI, and cytb genes revealed that the new species is the sister taxon to Amolops ottorum with strong support. Genetically, the new species differs from A. ottorum by 5.0% in cytb sequences. Morphologically, the new species can be distinguished from known congeners by the combination of the following characters: true dorsolateral folds absent, but dorsolateral folds formed by series of glands present; circummarginal groove on tip of first finger absent; body size small (males SVL 33.0–35.1 mm and female SVL 41.3 mm); HW/SVL 0.32‒0.35; UEW/SVL 0.08‒0.10; THL/SVL 0.52‒0.56; vomerine teeth absent; interorbital distance narrower than internarial distance; tympanum distinct, less than half eye diameter; supratympanic fold present, indistinct; a pair of large tubercles on sides of cloaca; tibiotarsal articulation reaching beyond anterior corner of eye; and vocal sac absent. The cladogenesis events within the A. mantzorum group rapidly occurred from Pliocene 4.23 Mya to Pleistocene 1.2 Mya, coinciding with the recent intensive uplift of the Qinghai-Tibetan Plateau since the Pliocene. Combining findings in this study with the most recent taxonomic progress, we consider that there are 20 known Amolops species in Yunnan, China, accounting for the highest proportion of amphibian diversity of Yunnan, and five of them belong to the A. mantzorum group. Among different subfauna and water systems in Yunnan, the species diversity of Amolops in northwestern Yunnan and Nu River Basin is highest. [ABSTRACT FROM AUTHOR]

The Karpathos water frog (Pelophylax cerigensis) is classified as Critically Endangered according to the IUCN Red List and its distribution is restricted on the island of Karpathos, South Aegean Sea. Utilizing a next generation sequencing approach, we obtained whole mitochondrial genomes of P. cerigensis to determine the species phylogenetic position within the genus Pelophylax and to clarify the phylogenetic relationship between the species' population on Karpathos Island and the population of P. cf. bedriagae from the neighboring Rhodes Island. High-throughput sequencing generated mean ± SD = 227 945 ± 18 306 reads averaged per sample. High quality reads were assembled resulting in the complete mitogenome of P. cerigensis of a total size of 17 922 bp. Mitogenome organization was similar to other Pelophylax species, comprising of 13 Protein Coding Genes (PCGs), 22 tRNAs, two rRNAs and one Control Region. Overall mean genetic distance for the 13 PCGs, within the Ranidae family, ranged from 8.01% (COIII) to 11.6% (ATP8), while ratios of synonymous and non-synonymous substitutions were <1 in all the 13 PCGs, indicating purifying selection. Maximum Likelihood and Bayesian Inference analyses based on the concatenated sequences of 13 PCGs and two rRNAs (12S and 16S), showed that individuals from Karpathos and Rhodes form a well-supported monophyletic group with low genetic distance between them (p-distance = 0.1%). Hence, the Rhodes populations seem to belong to P. cerigensis and not to P. bedriagae as formerly thought, highlighting the need for revision of P. cerigensis current conservation status as well as further examination of the P. bedriagae species group. [ABSTRACT FROM AUTHOR]

Geographic peculiarities of population structure and hemicloning reproduction of the water frog Pelophylax esculentus complex of 904 samples within southern East European Plain were analyzed. The proportion of populations of P. ridibundus is 0.667 against those 0.042 of P. lessonae. The RE-type populations are the most common among mixed ones (0.153). The colonies of the two parental species and P. kl. esculentus (REL-type), as well as those of P. lessonae with P. kl. esculentus (LE-type), have the frequencies 0.072 and 0.046, respectively. All-hybrid populations (E-type) are not numerous across the region (0.017). In the populations of Central, Northern and Western Ukraine, the P. lessonae genome is eliminated during gametogenesis within hybrids while in the Lower Dnieper and Lower Danube drainages, genome of P. ridibundus is eliminated. In the Eastern Ukraine populations, hybrids usually produce diploid gametes or haploid gametes with the P. ridibundus genome, less often with the chromosome set of P. lessonae only, and even more rarely a mixture of different types of gametes. The predominance of P. ridibundus in hybrid communities and the elimination of the P. lessonae genome in hybrids inevitably leads to the transformation of hybrid populations into "pure" R-type populations. This circumstance makes hybridization with P. ridibundus a factor in the shrinking of P. lessonae populations. That trend is especially expressed in the Forest steppe zone, where hybridization proceeds most intensively, the P. lessonae genome is eliminated in hybrids, and unstable populations with a numerical superiority of P. ridibundus predominate. [ABSTRACT FROM AUTHOR]

In this scientific work are exposed data with reference to the description of the diversity of the helminthic fauna of ecaudata amphibians from Ranidae and Bufonidae families, and the determination of its role as vectors for various groups of helminths to wild and domestic animals. As result of helminthological investigations during 2020-2022 years, 17 helminths species (secernentea, trematoda, palaeacanthocephala) was established: H. variegatus Rudolphi, 1819; G. varsoviensis Sinitzin, 1905;C.urniger Rudolphi, 1819; P. robusta Szidat, 1928; P. brumpti Buttner, 1951; P. confusus Looss, 1894; T. excavata Rudolphi, 1803; D. subclavatus Pallas, 1760; O. ranae Froelich, 1791 S. falconis Szidat, 1928; H. cylindracea Zeder, 1800; P. medians Olsson, 1876, C. ornata Dujardin, 1845; O. filiformis Goeze, 1782; I. neglecta Diesing, 1851; S. lupi Rudolphi, 1809; A. ranae Schrank, 1788). Of the 17 helminth species detected in amphibians, a special importance is attributed to the presence of 4 species of medical-veterinary importance helminths (Spirocerca lupi, Codonocephalus urniger, Parastrigea robusta, Strigea falconis), which can cause sterility, parastrigeosis and strigeosis in birds, as well as spirocercosis in dogs, foxes, wolves and occasionally in goat, horse, cattle and other. [ABSTRACT FROM AUTHOR]

Rana coreana is a brown frog species native to the Korean Peninsula. We characterized the complete mitochondrial genome of the species. The mitochondrial genome sequence of R. coreana is 22,262 bp and comprises 13 protein-coding genes, two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and two control regions (CRs). The CR duplication and gene organization were identical to those observed in Rana kunyuensis and Rana amurensis. A total of 13 protein-coding genes were used to examine the phylogenetic relationships between this species and the genus Rana. R. coreana living on the Korean Peninsula, formed a cluster with R. kunyuensis and R. amurensis, with R. coreana showing the closest phylogenetic affinity for R. kunyuensis. [ABSTRACT FROM AUTHOR]

The aims of this study were to determine the diversity of anurans and the distribution of their helminth parasites at Fraser's Hill and Sungai Jeriau, Pahang. Anurans were captured at night, and their organs (i.e., lungs, liver, heart and digestive tract) were collected for parasite isolation. Parasite identification was performed using iodine staining under a light microscope. Ranidae were the dominant anuran family at both study sites, and their distributions were significantly different (p<0.05) between sites. A total of 97 anurans were captured and 63% were infected with helminth parasites. Nematodes were the most common parasite identified. A positive correlation between the weight of anurans and the number of parasites was observed. The study showed that Fraser's Hill and Sungai Jeriau have a diverse population of anurans and helminth parasite distribution. This finding is essential for insights into anuran ecology and infection to monitor their survival. [ABSTRACT FROM AUTHOR]

In defensive mimicry, resemblance between unequally defended species can be parasitic; this phenomenon has been termed quasi-Batesian mimicry. Few studies have used real co-mimics and their predators to test whether the mimetic interactions were parasitic. Here, we investigated the mimetic interaction between two well-defended insect species, the bombardier beetle Pheropsophus occipitalis jessoensis (Coleoptera: Carabidae) and the assassin bug Sirthenea flavipes (Hemiptera: Reduviidae), using their potential predator, the pond frog Pelophylax nigromaculatus (Anura: Ranidae), which coexists with these insect species in the same habitat in Japan. We observed behavioural responses of this frog species (adults and juveniles) to adult Ph. occipitalis jessoensis and adult S. flavipes under laboratory conditions. Among the frogs, 100% and 75% rejected Ph. occipitalis jessoensis and S. flavipes, respectively, suggesting that, compared with the assassin bug S. flavipes, the bombardier beetle Ph. occipitalis jessoensis is more well-defended against frogs. An assassin bug or a bombardier beetle was provided to a frog that had encountered the other insect species. Frogs with a history of assassin bug encounter demonstrated a lower rate of attack toward bombardier beetles. Similarly, frogs with a history of bombardier beetle encounter demonstrated a lower rate of attack toward assassin bugs. Therefore, both the bombardier beetle Ph. occipitalis jessoensis and the assassin bug S. flavipes benefit from the mimetic interaction. [ABSTRACT FROM AUTHOR]

The PacBio® HiFi sequencing method yields highly accurate long-read sequencing datasets with read lengths averaging 10-25 kb and accuracies greater than 99.5%. These accurate long reads can be used to improve results for complex applications such as single nucleotide and structural variant detection, genome assembly, assembly of difficult polyploid or highly repetitive genomes, and assembly of metagenomes. Currently, there is a need for sample data sets to both evaluate the benefits of these long accurate reads as well as for development of bioinformatic tools including genome assemblers, variant callers, and haplotyping algorithms. We present deep coverage HiFi datasets for five complex samples including the two inbred model genomes Mus musculus and Zea mays, as well as two complex genomes, octoploid Fragaria × ananassa and the diploid anuran Rana muscosa. Additionally, we release sequence data from a mock metagenome community. The datasets reported here can be used without restriction to develop new algorithms and explore complex genome structure and evolution. Data were generated on the PacBio Sequel II System.

Background The Nidirana Dubois, 1992 exhibit a ubiquitous presence in East and Southeast Asia, spanning from Japan west to southern China and from northern Thailand to northern Vietnam and Laos in the south. The taxonomic categorisations pertaining to this genus continue to be a subject of debate, particularly with regard to those species that possess broad geographical distributions. In China, 18 species of Nidirana are currently recognised. New information We describe a new species of this genus from south-western China. Mitochondrial 16S and COI gene phylogenetic analyses support the new species as an independent clade nested within the Nidirana. The new species is phylogenetically close to N. yaoica, with a genetic distance of 2.5% from its sister taxon. Morphologically, the new species can be distinguished from congeners by a combination of the following characteristics: males relatively small (SVL 41.8-43.3 mm); lateroventral grooves present on both fingers and toes; relative finger length II < I < IV < III; tibio-tarsal articulation reaching to the level of the eye or nostril; a pair of external subgular vocal sacs in males; one single nuptial pad on the dorsal surface of the base of the first finger in males during the breeding season; webbing formula I 1/2 - 1 II 1/2 - 2 III 1 - 2 1/2 IV 2 - 1V. [ABSTRACT FROM AUTHOR]

We provide an expanded description of the tadpole of Amnirana albolabris (Ranidae) that includes external linear morphometrics and colouration across a developmental series ranging from Gosner stages 26–42. This description is based on material collected in Batéké Plateau National Park in south-eastern Gabon. The diurnal tadpoles are strikingly bright orange in life, a colouration that provides effective crypsis for the tannic waters in which they live. We also provide a comparative table for all of the described Amnirana tadpoles. The tadpole of A. albolabris can be identified in life by its unique colouration or in preservative by the seven prominent skin glands, assumed to contain defensive toxins. [ABSTRACT FROM AUTHOR]

The anomaly P is a mass morphological anomaly found in some populations of anuran amphibians (water frogs of the genus Pelophylax and toads of the genera Bufo and Bufotes) caused by the parasitic flatworm Strigea robusta. Minimum dose of cercariae for the appearance of the anomaly P remains unknown. However, it is important information for understanding of host population dynamics after invasion and the effects of the parasite on the second intermediate hosts. Herein, the invasion properties of S. robusta in Pelophylax lessonae tadpoles (Anura: Ranidae) and minimum dose for appearance of mild and severe forms of the anomaly P syndrome were described after direct experiments with certain numbers of cercariae exposure. Experimental groups of tadpoles have been exposed to eight doses of cercariae (2, 4, 6, 8, 10, 12, 14 and 16). A total of 63.8% tadpoles survived to the end of this experiment. It was revealed that a mild form of the anomaly P (polydactyly) can appear after infection by two cercariae, while the severe form traits appear after infection by four cercariae. The mean number of detected encysted metacercariae was reached to 53.5%. Differences in infection rates can be explained by the presence of an individual immune response in tadpoles or by the presence of different genetic lineages of the parasite infecting the same snail, which have different infectious potential. Low doses of infection leading to the induction of anomalies characterize S. robusta as a highly pathogenic species for amphibian species that are susceptible to infection and show an abnormal phenotype. [ABSTRACT FROM AUTHOR]

Seventeen nominal species of the ranid frog genus Amolops Cope, some of which are based on unverified historical records, are reported from India. Herein, we describe a new species of Amolops of the marmoratus group from a cave ecosystem. This is an uncommon habitat for this group of frogs, which is commonly found around cascades. The Siju Cave, from which four specimens of the new species were collected is a natural limestone cave located in the South Garo Hills District of Meghalaya, Northeast India. The new species is separated from other congeners based on morphological and genetic differences and is also geographically isolated from its sister species. [ABSTRACT FROM AUTHOR]

Abstract Restriction‐site‐associated DNA sequencing (RADseq) has become an accessible way to obtain genome‐wide data in the form of single‐nucleotide polymorphisms (SNPs) for phylogenetic inference. Nonetheless, how differences in RADseq methods influence phylogenetic estimation is poorly understood because most comparisons have largely relied on conceptual predictions rather than empirical tests. We examine how differences in ddRAD and 2bRAD data influence phylogenetic estimation in two non‐model frog groups. We compare the impact of method choice on phylogenetic information, missing data, and allelic dropout, considering different sequencing depths. Given that researchers must balance input (funding, time) with output (amount and quality of data), we also provide comparisons of laboratory effort, computational time, monetary costs, and the repeatability of library preparation and sequencing. Both 2bRAD and ddRAD methods estimated well‐supported trees, even at low sequencing depths, and had comparable amounts of missing data, patterns of allelic dropout, and phylogenetic signal. Compared to ddRAD, 2bRAD produced more repeatable datasets, had simpler laboratory protocols, and had an overall faster bioinformatics assembly. However, many fewer parsimony‐informative sites per SNP were obtained from 2bRAD data when using native pipelines, highlighting a need for further investigation into the effects of each pipeline on resulting datasets. Our study underscores the importance of comparing RADseq methods, such as expected results and theoretical performance using empirical datasets, before undertaking costly experiments.

Skeletochronology is a reliable method for estimating the age and growth rate of many ectothermic vertebrates, including amphibians. The Levant green frog, Pelophylax bedriagae (Ranidae), is a relatively large frog distributed in the western and northern parts of Iran. The age structure of Pelophylax bedriagae was determined by examining 52 females and 39 males collected from Kohgilouyeh and Bouyerahmad Provinces (Yasouj and Basht). The age range of the two populations is three to 10 years. The maximum age for males and females is 10 and eight years, respectively. The highest age distribution for males is six years (17.6%) and four and six years (15.4%) for females. On average, males (6.2±1.4 years) are older than females (5.2±1.3 years). Male and female body size is correlated with age within both populations. However, despite being significantly different in average body size, the average age of the two populations (Yasouj vs. Basht) is not significantly different. [ABSTRACT FROM AUTHOR]