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The genus Elaphe is a highly diverse snake group with wide distribution in Eurasia. Here, based on morphological comparisons and molecular data, we describe a new species of this genus from western Sichuan, China. Bayesian inference and maximum-likelihood analyses of two mitochondrial DNA fragments (CO1 and 12S) showed that the new taxon differs from its congeners (CO1-based p-distance ≥ 4.1%). Morphologically and ecologically, the new species can be diagnosed from other species by a combination of the following characters: 1) medium body size, < 780 mm in total length; 2) midbody dorsal scales in 23 rows generally, not keeled; 3) ventrals 169–180 and subcaudal pairs 56–63; 4) first preocular docked with frontal; 5) internasal scales approximately trapezoidal; 6) length of gap between internasals more than 3/5 that between prefrontal; 7) length of tip of snout to frontal slightly larger than length of frontal; 8) ovoviviparous. Currently, the new species is known only from the Sichuan and Shaanxi provinces in China. This new species brings the total number of species in the genus Elaphe to 18.

BackgroundResource allocation trade-off between storage and somatic growth is an essential physiological phenomenon in animals. Revealing its patterns and underlying mechanisms are fundamental for behavior, evolutionary, and population ecological studies. Currently, our understanding of the real-time resource allocating patterns in animals is still limited, and the underlying metabolic mechanisms have been rarely investigated. The life strategy of amphibian larvae relies on precise coordination between storage and somatic growth, which makes them good model for studying this issue.ResultsHere, the resource allocation strategy was investigated for Rana omeimontis tadpoles, who exhibit prominent hepatic fat-accumulation. Results showed that their ontogenetic fat accumulation emerged when tadpoles grew to a body weight range of 30–50 mg, where their fat storage had a high priority in resource allocation. Beyond this range, the resource proportion for somatic growth increased, but continuous storage investment was likely maintained to kept higher body fat index in larger individuals. This seeming paradoxical allocation pattern could be explained by assuming a positive relationship between storage abundance and the investment to somatic growth. This speculation was supported by the observation that storage had the priority in resource allocation to reach a higher body fat index before increment in body weight when food level increased. Moreover, it was also supported by the metabolic pattern that presented lipid-based energy metabolism after ontogenetic fat accumulation, and activating the mobilization of fat storage in the liver can promote the somatic growth. In short, fat synthesis and fat accumulation in the liver may well modulated the resource allocation to somatic growth, and their liver likes a reservoir with valves to regulate energy flow for the downstream developmental processes.ConclusionIn Rana omeimontis tadpoles, their hepatic fat level positively modulated the resource allocation to somatic growth through lipid-based energy metabolism. We reveal the real-time resource allocation pattern in an amphibian tadpole and explain it at molecular level. These results likely provide a new mechanistic insight into the resource allocation in animals.

The niche divergence and potential climate change-induced loss of evolutionarily significant units (ESUs) of flagship amphibian species in China, the Chinese giant salamander clade, were investigated. We tested niche-related ecological hypotheses and identified suitable habitats that are essential for the conservation of ESUs in response to future climate change according to ecological niche models (ENMs). We predicted the localized habitat loss crisis of ESUs induced by global climate heating using the predicted climate derived from two representative concentration pathway (RCP) scenarios 2.6 and 8.5, respectively. In our study, a niche conservatism pattern was found between the two distinctive northern and southern ESUs with sufficient distributional records, but their niches were not equivalent. Furthermore, there was neither abrupt environmental change in nor remarkable biogeographic barriers between the suitable habitats of the species, as indicated by random linear, blob and ribbon range-breaking tests. Under the low-emission scenario RCP2.6, the northern ESU had a moderate loss of suitable range, while the southern ESU had range expansion in the 2070s. The climatic velocities were low in the ranges of both ESUs. However, under the high-emission scenario RCP8.5, the climatic velocities were found to become larger in the suitable ranges of both ESUs. Moreover, the northern ESU had severe habitat loss, bringing it to the edge of extinction, while the southern ESU also had intensified range loss. Considering this, climatic velocity can be an effective indicator of range loss. We argued conclusively that conservation prioritization of ESUs should effectively take into account the underlying geographic and ecological mechanisms driving the speciation process. The conservation of ESUs should consider the conservation of both evolutionary potential and ecological adaptation capacity of each lineage. The present study provided practical guidelines for repopulation programs for endangered species and the conservation of evolutionary diversity.

The Taliang crocodile newt, Liangshantriton taliangensis, which is endemic to south-western China, is a rare salamandrid species with a distinct evolutionary history. Using combined field observations and captive experiments, we studied the courtship behaviour and male sexual interference of this species and composed a complete ethogram of its courtship behaviour. Unlike previous reports on sperm transfer, male L. taliangensis did not deposit spermatophores during ventral amplexus and females did not pick up sperm masses in this courtship phase. Sperm transfer was only performed during arm-hooking pin-wheel circling, which distinguishes L. taliangensis from Tylototriton species and supports the validity of genus Liangshantriton. Whether L. taliangensis shows bimodality in sperm transfer needs to be explored in additional populations. In the presence of sexual competitors, male L. taliangensis adjusted the duration of their behaviour. We found that males with longer snout-vent length, heavier mass, and higher tailfins may have an advantage in intrasexual competition.

The complete mitochondrial genome of the Microhyla taraiensis from Eastern Nepal was sequenced. The genome has a typical gene order identical to most of other anuran species. The entire mtDNA of this species, 16,764 bp in length, containing 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a control region. Phylogenetic relationships was constructed based on the complete mitogenome of M. taraiensis and other species of Microhylidae, using Bayesian inferences and Maximum likelihood approaches, and supports the monophly for this family. This work contributes to basic molecular data which is critical for further genetic research and conservation of this newly described species.

Transcriptomics has the potential to discover new RNA virus genomes by sequencing total intracellular RNA pools. In this study, we have searched publicly available transcriptomes for sequences similar to viruses of the Nidovirales order. We report two potential nidovirus genomes, a highly divergent 35.9 kb likely complete genome from the California sea hare Aplysia californica, which we assign to a nidovirus named Aplysia abyssovirus 1 (AAbV), and a coronavirus-like 22.3 kb partial genome from the ornamented pygmy frog Microhyla fissipes, which we assign to a nidovirus named Microhyla alphaletovirus 1 (MLeV). AAbV was shown to encode a functional main proteinase, and a translational readthrough signal. Phylogenetic analysis suggested that AAbV represents a new family, proposed here as Abyssoviridae. MLeV represents a sister group to the other known coronaviruses. The importance of MLeV and AAbV for understanding nidovirus evolution, and the origin of terrestrial nidoviruses are discussed., Graphical abstract fx1

Measurements of historical specimens are widely applied in studies of taxonomy, systematics, and ecology, but biologists often assume that the effects of preservative chemicals on the morphology of amphibian specimens do not affect their analyses. We compared the body length and body mass of 14 live and preserved (up to 10 years) amphibian species and found that the body length and body mass of preserved specimens significantly decreased by 7.1% and 26.7%, respectively, compared to those measurements of their live counterparts. Additionally, there was greater body length (3.6%) and body mass (6.6%) shrinkage in the order Urodela than in the order Anura, but there were no significant differences in body length and body mass shrinkage between males and females. Furthermore, preservation apparently distorted the magnitude of the intersexual and interspecific differences in body length observed in the fresh specimens. When species were compared, we found that the shrinkage was proportionately greater in longer species, while the body mass of heavier individuals shrank proportionately less than that of lighter individuals. Due to the effects of preservation on amphibian morphology, we propose parsimonious conversion equations to back-calculate the original body length and body mass of study animals for researchers working with historical data because morphological data from preserved specimens may lead to incorrect biological interpretations. Therefore, researchers must correct for errors due to preservation effects that may lead to the misinterpretation of results.

The complete mitogenome of Leishan moustache toad, Vibrissaphora leishanensis, is determined. The mitogenome size is 17,485 bp, containing 13 protein-coding genes, 2 rRNA genes, 23 tRNA genes and a control region (D-loop). The base composition of the whole genome is 28.1% A, 32.6% T, 24.4% C and 14.8% G. As observed in this genus before, this mitogenome also appears a tandem duplication of tRNAMet gene. This study will provide fundamental data for further research to resolve population genetics of this species and systematic problems of the genus Vibrissaphora.