查看更多>>摘要：Human disturbances are considered to break reproduction barriers among species.Significant increases in hybridization events have been reported among a large number of taxonomic groups in anthropogenic environments,providing novel insights into species evolution mechanisms and conservation management in the Anthropocene.The Eastern Golden Frog(Pelophylax plancyi)and Black-Spotted Frog(P.nigromaculatus)are two sympatric anuran species with a long history of mitochondrial genome introgression in highly urbanized continental East Asia.However,there is only limited understanding of the pattern of their contemporary hybridization and factors influencing their interspecific relationship under anthropogenic disturbances.Here,interspecific hybridization between P.plancyi and P.nigromaculatus at the population level was investigated in Shanghai.All except two haplotypes obtained from both species in Shanghai were mixed together,and located in the introgression clade,implying multiple ancient mitochondrial introgression events occurred in the populations of our study area.Asymmetric genetic introgression was detected by microsatellite markers,with 0.7%of P.plancyi and 14.6%of P.nigromaculatus identified as contemporary admixed individuals.Consistent with the trend of population density,higher genetic diversity of neutral microsatellite loci was found in the more abundant P.plancyi;however,variation in mitochondrial(Cyt-b)and nuclear(POMC)genes was higher in relatively rare P.nigromaculatus.The population density of P.plancyi and number of water patches within local habitats were significantly positively correlated with both occurrences and proportions of admixed individuals in the populations of P.plancyi and P.nigromaculatus.Considering the prevalent transformation of habitats in urbanized areas,these results imply that a high population density in isolated artificially altered habitats is likely to increase interspecific hybridization.Thus,population monitoring and improvement of landscape connectivity between habitats would be needed to control the intensity of interspecific hybridization between P.plancyi and P.nigromaculatusin anthropogenic-disturbed environments.
查看更多>>摘要：A new horned toad species,Boulenophrys elongata sp.nov.,is described from Mt.Lianhua,Huidong County,eastern Guangdong,China.The new species is phylogenetically closest to B.brachykolos,which is restricted to the east of the Pearl River Estuary(i.e.,Shenzhen City and Hong Kong SAR).The new species can be distinguished from all recognized congeners by a combination of morphological characters and genetic divergences in the combined mitochondrial 16S,12S and CO1 genes.We recommend the new species be listed as Data Deficient(DD)in the IUCN categorization,pending further investigation.
查看更多>>摘要：A new species of the genus Brachytarsophrys,named Brachytarsophrys wenshanensissp.nov.,has been identified in southeastern Yunnan,China.This new species can be readily distinguished from other known congeners by both morphological criterion and molecular analysis of three mitochondrial gene segments:16S,COI,and Cytb.This classification is based on the following morphological characters:(1)medium body size(SVL 83.8-85.1 mm in two adult males);(2)enormous head,with head width nearly 1.2 times the length;(3)tongue pyriform,feebly notched;(4)non-meeting heels;(5)male lacking nuptial pad;(6)tibiotarsal articulation reaching angle of mouth when hindlimbs are extended forward alongside the body;(7)absence of outer metatarsal tubercle,inner metatarsal tubercle elliptic and approximately equal to first toe;(8)rudimentary toe webbing,webbing formula:Ⅰ(2-)-(2++)Ⅱ(2-)-(3++)Ⅲ(21/2)-(4)Ⅳ(4+)-(22/3)Ⅴ;(9)lateral fringes narrow;(10)dermal ridge or glandular fold on dorsum absent;(11)pectoral glands distinct and irregular,femoral gland small.Our work increases the number of species within the genus Brachytarsophrys to 9.
查看更多>>摘要：In the present study,we propose the synonymization of Kurixalus silvaenaias with Kurixalus qionglaiensis.This conclusion is based on morphological examination and phylogenetic analysis of a series of newly collected specimens,as well as the type series of both nomenclatures.The publication dates of the two species were determined according to the related articles of the International Code of Zoological Nomenclature.Of note,the ZooBank registrations for both species are invalid.Consequently,the publication of K.silvaenaias does not qualify as a published work and the correct publication date of K.qionglaiensis should be the date on which it was physically printed.Furthermore,based on the results presented in this study and its original description,the proposal of K.inexpectatus is deemed untenable and should,therefore,be considered a junior synonym of K.idiootocus.We further provide suggestions for the authors,editors,and publishers who are working on taxonomic publications,as well as for ZooBank to improve the registering service.
查看更多>>摘要：Prey species may have their own optimal escape strategy to balance predation risks and the energetic cost of fleeing.Some species have an advantage when maintaining a short fleeing distance,while others may favour an earlier escape based on microhabitat,size,or body condition.Here,we examined the escape behaviour of the three syntopic Northeast Asian anuran species:Mongolian toads(Strauchbufo raddei),Amur brown frogs(Rana amurensis),and Japanese treefrogs(Dryophytes japonicus)in Mongolia,Russia,China and DPR Korea.We examined flight initiation distance(FID;the distance from a potential predator to the point when the individual starts to flee)and distance fled(DF;distance between flight initiation and flight termination points)of each species and the effects of microhabitat,sex,and body size.Strauchbufo raddeiand R.amurensis had a longer FID than D.japonicus,and S.raddei also had a longer DF than D.japonicus.These trends remained similar when dividing FID and DF by a size proxy(snout-vent length)for all individuals.This suggests that the treefrog D.japonicus used a strategy to stay immobile even when they were detected,and the toad S.raddei reacted quicker and more sensitively to predators despite the presence of toxin.Female S.raddei had a significantly longer FID than males suggesting that females are more sensitive to predation risk in this species,but body size was not significant for any of the three species.Our results indicate that the three sympatric species have different escaping strategies,likely related to differences in physiology and crypticity.
查看更多>>摘要：We studied sexual dimorphism in body size and shape and female reproductive characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China.In our sample the largest female and male were 61.1 and 55.2 mm snout-vent length(SVL),respectively.The mean SVL was larger in adult females(52.0 mm)than in adult males(48.3 mm).Juveniles were sexually dimorphic in head length but not in other examined morphological variables.Adult males were longer in head length and shorter in abdomen length and fore-limb length than adult females of the same SVL.Ontogenetic shifts in sexual dimorphism in body shape were evident,as revealed by the fact that morphological differences between the sexes were more pronounced in adults than in juveniles.Females produced a single litter of 3-6 offspring per season from early August to early September.Litter size,litter mass and offspring(neonate)mass were positively related to female SVL.Neonate mass was independent of relative fecundity.From the above findings we draw three main conclusions.First,females are the larger sex in T.hainanus,and sexual dimorphism in body shape is more pronounced in adults than in juveniles.Second,larger female T.hainanus produce more and larger offspring and thus heavier litters than smaller ones.Third,the offspring size-number trade-off does is not evident in T.hainanus.
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