A new species of genus Megophrys from Gaoligong Mountains, Yunnan Province, China is described. Phylogenetic analyses based on mitochondrial DNA and nuclear DNA all clustered the new species as an independent clade nested into the subgenus Panophrys. The smallest genetic distance based on 16S rRNA gene between the new species and its congeners was 3.0%. The new species could be identified from its congeners by a combination of following characters: moderate body size (SVL 31.0–34.8 mm in males); vomerine ridge weak, vomerine teeth absent; dorsal skin relatively smooth; tongue slightly notched behind; tympanum rounded and relatively large, 0.54 times of eye length; a horn-like tubercle on edge of each upper eyelid small; tibio-tarsal articulation reaches middle eye when leg stretched forward; finger tips rounded, not expanded to small pad; toes with narrow fringes and rudimentary webbing; ventral hindlimbs semitransparent purplish with greyish white pigments; ventral body scattered with distinct dark patches in the middle.

An increasing number of studies have shown that warming also influences the animal gut microbiome (altering the community structure and decreasing its diversity), which might further impact host fitness. Here, based on an analysis of the stomach and gut (the entire intestine: from the anterior intestine to the cloaca) microbiome in laboratory larva of giant salamanders (Andrias davidianus) under different living water temperatures (5, 15, and 25°C) at two sample time points (80 and 330 days after the acclimation), we investigated the potential effect of temperature on the gastrointestinal microbiome community. We found the significant Interaction between sampling time and temperature, or type (stomach and gut) on Shannon index in the gastrointestinal microbiome of the giant salamanders. We also found the significant difference in Shannon index among temperature groups within the same sample type (stomach or gut) at each sample time. 10% of variation in microbiome community could be explained by temperature alone in the total samples. Both the stomach and gut microbiomes displayed the highest similarity in the microbiome community (significantly lowest pairwise unweighted Unifrac distance) in the 25-degree group between the two sampling times compared to those in the 5-degree and 15-degree groups. Moreover, the salamanders in the 25°C treatment showed the highest food intake and body mess compared to that of other temperature treatments. A significant increase in the abundance of Firmicutes in the gastrointestinal microbiome on day 330 with increasing temperatures might be caused by increased host metabolism and food consumption. Therefore, we speculate that the high environmental temperature might indirectly affect both alpha and beta diversity of the gastrointestinal microbiome.

Global climatic transitions and Tibetan Plateau uplifts are hypothesized to have profoundly impacted biodiversity in southeastern Asia. To further test the hypotheses related to the impacts of these incidents, we investigated the diversification patterns of the newt genus Tylototriton sensu lato, distributed across the mountain ranges of southeastern Asia. Gene-tree and species-tree analyses of two mitochondrial genes and two nuclear genes revealed five major clades in the genus, and suggested several cryptic species. Dating estimates suggested that the genus originated in the early-to-middle Miocene. Under different species delimitating scenarios, diversification analyses with birth-death likelihood tests indicated that the genus held a higher diversification rate in the late Miocene-to-Pliocene era than that in the Pleistocene. Ancestral area reconstructions indicated that the genus originated from the northern Indochina Peninsula. Accordingly, we hypothesized that the Miocene Climatic Transition triggered the diversification of the genus, and the reinforcement of East Asian monsoons associated with the stepwise uplifts of the Tibetan Plateau promoted the radiation of the genus in southeastern Asia during the Miocene-to-Pliocene period. Quaternary glacial cycles likely had limited effects on speciation events in the genus, but mainly had contributions on their intraspecific differentiations.

Background: Metamorphic climax is the crucial stage of amphibian metamorphosis responsible for the morphological and functional changes necessary for transition to a terrestrial habitat. This developmental period is sensitive to environmental changes and pollution. Understanding its metabolic basis and requirements is significant for ecological and toxicological research. Rana omeimontis tadpoles are a useful model for investigating this stage as their liver is involved in both metabolic regulation and fat storage. Results: We used a combined approach of transcriptomics and metabolomics to study the metabolic reorganization during natural and T3-driven metamorphic climax in the liver and tail of Rana omeimontis tadpoles. The metabolic flux from the apoptotic tail replaced hepatic fat storage as metabolic fuel, resulting in increased hepatic amino acid and fat levels. In the liver, amino acid catabolism (transamination and urea cycle) was upregulated along with energy metabolism (TCA cycle and oxidative phosphorylation), while the carbohydrate and lipid catabolism (glycolysis, pentose phosphate pathway (PPP), and β-oxidation) decreased. The hepatic glycogen phosphorylation and gluconeogenesis were upregulated, and the carbohydrate flux was used for synthesis of glycan units (e.g., UDP-glucuronate). In the tail, glycolysis, β-oxidation, and transamination were all downregulated, accompanied by synchronous downregulation of energy production and consumption. Glycogenolysis was maintained in the tail, and the carbohydrate flux likely flowed into both PPP and the synthesis of glycan units (e.g., UDP-glucuronate and UDP-glucosamine). Fatty acid elongation and desaturation, as well as the synthesis of bioactive lipid (e.g., prostaglandins) were encouraged in the tail during metamorphic climax. Protein synthesis was downregulated in both the liver and tail. The significance of these metabolic adjustments and their potential regulation mechanism are discussed. Conclusion: The energic strategy and anabolic requirements during metamorphic climax were revealed at the molecular level. Amino acid made an increased contribution to energy metabolism during metamorphic climax. Carbohydrate anabolism was essential for the body construction of the froglets. The tail was critical in anabolism including synthesizing bioactive metabolites. These findings increase our understanding of amphibian metamorphosis and provide background information for ecological, evolutionary, conservation, and developmental studies of amphibians.

A new species of the microhylid frog genus Microhyla is described from the Fanjing Mountain of Guizhou Province, China. Phylogenetic analyses based on DNA sequences of the the mitochondrial 12S rRNA, 16S rRNA and COI genes supported the new species as an independent lineage, closely related to M. beilunensis, M. mixtura and M. okinavensis. The uncorrected genetic distance on 16S rRNA gene between the new species and its closest congeners M. beilunensis, M. mixtura and M. okinavensis are 3.5%, 4.6% and 4.6% respectively. The new species is distinguished from its congeners by a combination of the following morphological characters: (1) body of medium size (SVL 19.0–22.7 mm in males and 22.5–23.0 mm in females); (2) disk and dorsal median longitudinal groove on finger tips absent; (3) toe with rudimentary webbing at base; (4) disk with dorsal median longitudinal groove present at toe tips except for the toe I; (5) two metatarsal tubercles on palm; (6) tibiotarsal articulation reaching the level between eye to nostril when leg stretched forward; (7) a distinct V-shaped white stripe on the upper midsection. The new species is known only from the type locality, and thus the finding of it has contributed to the endemic species diversity of China. It is needed to take strategy to protect the species and habitats due to the increased threats of environmental changes.