查看更多>>摘要:The gut microbiota plays a pivotal role in the maintenance of health for amphibians,and it has been fully recognized,but the effectiveness of various influencing factors has not yet been fully clarified.Although this association should be considered while the amphibian order Caudata is facing a severe situation of population decline and extinction,there is little understanding of the association between diets and the diversity of gut microbiota in the amphibian order Caudata.Here,we conducted an extensive analysis of the gut microbiota of Cynops orientalis fed different diets using functional prediction and 16S rRNA amplicon sequencing techniques.First,we found that wild individuals had greater gut microbial diversity and richness in comparison to captive individuals.Second,we identified the bacterial taxa associated with diets and observed differences in the relative abundance of gut microbiota among people on various diets.Finally,we have a predictive comprehension of the selection and adaptative significance of shared core ASVs in the gut microbiota in maintaining the healthy survival of C.orientalis in a large-scale spatiotemporal map.Our study emphasizes how diets alter the gut microbiota of Caudata and offers fresh perspectives on the conservation and captive management of species in Caudata.
查看更多>>摘要:Considering the increased anthropogenic impacts,species with a limited range and low detectability often lack fundamental information and conservation actions,placing them at a high risk of endangerment.The Chinting alpine toad Scutiger chintingensis is a rare mountain amphibian endemic to the eastern margin of the Qinghai-Xizang Plateau in China.Within its whole distribution range,only three known populations(Wolong,Emei,and Wawu)exist and no recent population status report has been documented for this species over the past two decades.From 2020 to 2023,we investigated the species distribution,and assessed the risk factors for the main populations.We recorded this species in all distribution areas,and updated a new distribution site with a lower elevation limit.The relative population density was 0.024±0.012 ind./m2 on Mount Emei,whereas only 0.008±0.017 ind./m2 on Mount Wawu.No significant difference was observed in the number of individuals between the two populations;however,the relative population density was significantly different.Sewage and waste discharge resulting from the construction of scenic areas,as well as disturbances from tourism,were the primary anthropogenic factors that influenced the survival of this species.Our results provide the updated information on the distribution and population status of the Chinting alpine toad,and suggest that unrecorded populations,as well as a wider elevation range,may exist for this species.Our findings emphasise the importance of timely updates of species distribution and population information and offer a basis for the future conservation of endangered amphibians.
查看更多>>摘要:Seasonal variation of hearing sensitivity has been observed in many vertebrate groups with obvious vocal behaviors.Circulating hormones,conspecific calling signals,and temperature are potential factors that drive these plasticity patterns.Turtles have a hearing range that appears to be limited to under 1.5 kHz and are often thought to be non-vocal;thus,they are commonly neglected in vocal communication research.In this study,we aimed to determine whether the auditory phenotype exhibits seasonal variation in sensitivity and to analyze the potential factors driving such variation patterns in turtles.We measured hearing sensitivity and sex hormone levels in female(estradiol)and male(testosterone and dihydrotestosterone)Red-eared sliders(Trachemys scripta elegans)during spring and winter.The results showed that auditory brainstem response(ABR)thresholds were significantly lower in spring than in winter at a frequency range of 0.5-0.9 kHz.The hearing-sensitivity bandwidth was wider,and the ABR latency was significantly shorter in spring than in winter.No significant differences were found in estradiol,testosterone,and dihydrotestosterone levels in T.scripta elegansbetween spring and winter.This study is the first to reveal the seasonal variation of peripheral hearing sensitivity in turtles,a special animal group with limited hearing range and less vocalization.Temperature variations may be used to explain these seasonal effects,but further research is required to confirm our findings.
查看更多>>摘要:The Asian leaf litter toad genus Leptobrachella contains more than 100 species widely distributed in southwestern Asia.However,the systematic profiles of this group remain unresolved.Osteological morphology is important for taxonomic and phylogenetic studies.However,few studies have focused on the osteology of the genus.Herein,we comprehensively described the osteological features of a representative species L.bijie based on micro-CT scanning and double-staining methods.The results show that the skull of adult L.bijie is well-ossified,exhibiting sexual dimorphism and minimal intraspecific variation.The skull length is slightly greater than the width,with the maxilla slightly overlapping with the quadratojugal.The nasal connects with the sphenethmoid in males,but only part or not connects with the sphenethmoid in females.The transverse processes of the sacrum are robust and symmetrically butterfly-shaped,and the presacral vertebrae are procoelous.The pectoral girdle is arciferous.The phalangeal formula is 2-2-3-3 for the hand,and 2-2-3-4-3 for the foot.This study provides the first detailed and comprehensive osteological accounts of the genus Leptobrachella.
查看更多>>摘要:Chinese alligator hatchlings in captivity are fragile and have a high mortality rate within first year.The body mass gain of reptile animals is closely related to their feeding behavior and gut microbiota.This study analyzed the intrinsic factors influencing the allometric growth of Chinese alligator hatchlings based on their body mass gain,feeding behavior,and gut microbiota.This information would enhance the health management of Chinese alligator hatchlings.There was a significant correlation between the total distance moved,the average number of conspecifics nearby,and body mass gain.Chinese alligator hatchlings with a greater growth rate showed greater activity and more independent behavior during feeding than those with a lower growth rate.Moreover,after feeding started,some functions of the gut microbiota showed significant relationships with growth rate and feeding activity.Chinese alligator hatchlings with a greater growth rate showed greater levels of heme biosynthesis than those with a lower growth rate,and feeding activity was inhibited by long-chain fatty acid biosynthesis.These results elucidate the relationships between health,feeding behavior,and the gut microbiota of Chinese alligator hatchlings.Understanding the intrinsic factors of their health and feeding behavior can improve the health management of Chinese alligator hatchlings in captivity for conservation.
查看更多>>摘要:The genus Scincella Mittleman,1950,within the family Scincidae,is a diverse group comprising 39 described species.The taxonomy of the genus is complex due to morphological similarities among species,which often obscures the true extent of biodiversity,resulting in several undescribed species requiring further exploration.In China,particularly within the unique ecosystems of the Hengduan Mountains,the diversity of Scincella is notably underestimated,with only 12 species currently recognized.In the present study,we describe a new species of the genus Scincella,Scincella liangshanensissp.nov.,from Sichuan Province,Southwest China.Morphological characteristics and phylogenetic analyses revealed that the putative new species is distinct from all other known congeners.This discovery not only expands the known diversity of Scincella but also emphasizes the inadequacies in our current understanding of herpetological diversity in China.The addition of this species to the scientific record highlights the necessity for ongoing biodiversity assessments to uncover hidden species and enhance our understanding of the intricate web of life in one of the world's biodiversity hotspots.