The snakes comprising the monophyletic group referred to as ratsnakes are found throughout Asia,Europe and the New World.Recently,three snake samples likely belonging to the ratsnakes were collected in Zoige County,Si...The snakes comprising the monophyletic group referred to as ratsnakes are found throughout Asia,Europe and the New World.Recently,three snake samples likely belonging to the ratsnakes were collected in Zoige County,Sichuan Province,China.Species identity was difficult to delimit morphologically because the specimens were juveniles and partially damaged.Subsequently,a molecular phylogenetic approach was used.Portions of three mitochondrial genes(cyt b,ND4 and 12S rRNA) were sequenced and analyzed.The results showed that they were sister to the genus Elaphe.Very little genetic variation was found among the three samples.The minimum genetic distances between these samples and those within Elaphe were greater than any currently recognized species within the genus.We conclude that this likely represents a new species within the genus Elaphe.Adult specimens and a morphologic description are needed for further study.展开更多
The translocation of snakes has been viewed as a useful tool to augment declining populations and to mitigate human-wildlife conflicts, even though released snakes often exhibit relatively high mortality. We radio-tra...The translocation of snakes has been viewed as a useful tool to augment declining populations and to mitigate human-wildlife conflicts, even though released snakes often exhibit relatively high mortality. We radio-tracked 13 Amur Ratsnakes （Elaphe schrenckii） in the Woraksan National Park in South Korea from July 2008 to May 2009. Two of these snakes were residents, and 11 had been illegally captured in areas remote from the study site and were donated by the park office. During the study period, six of the translocated snakes were lost： two were killed by predators, one died of unknown causes, and the radio signals of three of the snakes were lost. In the field, the ratsnakes laid eggs in early August, moved into hibemacula in late November, and moved away from the hibemacula in mid-April. Compared to the resident snakes, five of the translocated snakes traveled approximately 1.3 times farther per week, and the home ranges of the translocated snakes were three to six times larger than those of the resident snakes. In addition, the translocated snakes were found underground more frequently than the resident snakes. The management recommendations resulting from this study will guide biologists and land use managers in making appropriate decisions regarding release sites and the use of gravid females in the translocation of this endangered ratsnake.展开更多
In this report, we describe morphological characteristics of a dicephalic Steppes Ratsnake （Elaphe dione） collected from the wild in 2011 in South Korea. The specimen has two heads and two long necks. Unlike normal ...In this report, we describe morphological characteristics of a dicephalic Steppes Ratsnake （Elaphe dione） collected from the wild in 2011 in South Korea. The specimen has two heads and two long necks. Unlike normal individuals, the dicephalic snake has divided ventral scales under the necks of the bifurcated columns. The snout- vent length （SVL） and overall total length of the individual are shorter than those of normal snakes of the same age. Nevertheless, the counts of nine different scale types that are often used for classification are all within the ranges of normal individuals. As far as we know, this is the first detailed morphological description of a dicephalic E. dione in the scientific literature.展开更多
Research on the ecological effect of microronamentations on the scale surface in reptiles has been carried out over the past few decades.It is found that the microornamentation pattern in reptiles is related to their ...Research on the ecological effect of microronamentations on the scale surface in reptiles has been carried out over the past few decades.It is found that the microornamentation pattern in reptiles is related to their habitats.This study examined the wettability on scale surface,as well as the differences in microornamentation on ventral scales from the mid-body region in three snake species,Hypsiscopus plumbea(aquatic),Oocatochus rufodorsata(semi-aquatic) and Elaphe carinata(terricolous).Moreover,the scale specimens were metallized and analyzed using scanning electron microscopy.Our results showed that there are microornamentations on the ventral scale surfaces of the tested species,which showed interspecific differences.To be specific,the aquatic snake shows the narrow,fine and regular denticulations which are connected to reduce friction and dirt shedding.By contrast,the terrestrial snake acquired the wider and shorter denticulation which would render more friction during locomotion but it shows greater water resistance to improve the capacity of dirt shedding and compensate for the disadvantage of short and wide denticulations.Additionally,the denticulation characteristics of the semi-aquatic snake fell in between those of aquatic and terrestrial snakes.Therefore,it is deduced in this study that the ventral scale microornamentations in snakes contribute to ecological adaptation to their preferential microhabitats.展开更多
Comparing mitochondrial and genomic phylogenies is an essential tool for investigating speciation processes,because each genome carries different inheritance properties and evolutionary characteristics.Furthermore,mit...Comparing mitochondrial and genomic phylogenies is an essential tool for investigating speciation processes,because each genome carries different inheritance properties and evolutionary characteristics.Furthermore,mitonuclear discordance may arise from ecological adaptation,historic isolation,population size changes,and sex-biased dispersal.Closely related taxa are expected to experience gene flow;however,this may not be true for insular populations or populations isolated in refugia.The four-lined snake Elaphe quatuorlineata has a fragmented distribution,separating populations of the Italian and Balkan Peninsulas,whereas several insular Aegean populations of significantly smaller body size(Cyclades island group and Skyros Island,Greece)are currently considered distinct subspecies.We constructed the species-tree phylogeny of this species utilizing genome-wide single nucleotide polymorphisms and a gene-tree based on complete cytochrome b sequences,aiming to detect convergence and discrepancies between biparentally and maternally inherited genomes.Population structuring,phylogenetic patterns and migration events among geographically defined lineages supported our hypothesis of isolation in multiple sub-refugia.Where biogeographical barriers did not restrict subsequent dispersal,extensive genetic exchange occurred between mainland Balkan populations.This process has led to the mitochondrial sweep of an ancestral mitolineage that survived only in peripheral(East Greece)and insular populations(North Cyclades and Skyros).The Central Cyclades represent an ancient lineage for both molecular markers that emerged almost 3.3 Mya.Considering their distinct morphology,insular E.quatuorlineata populations should be the future focus of an extensive sampling,especially since the mitonuclear discordance observed in this species could be related to ecological adaptations,such as the island-dwarfism phenomenon.展开更多
基金supported by the National Natural Science Foundation of China(30870290)the Science Research Program of Huangshan University(2006xkjq014)
文摘The snakes comprising the monophyletic group referred to as ratsnakes are found throughout Asia,Europe and the New World.Recently,three snake samples likely belonging to the ratsnakes were collected in Zoige County,Sichuan Province,China.Species identity was difficult to delimit morphologically because the specimens were juveniles and partially damaged.Subsequently,a molecular phylogenetic approach was used.Portions of three mitochondrial genes(cyt b,ND4 and 12S rRNA) were sequenced and analyzed.The results showed that they were sister to the genus Elaphe.Very little genetic variation was found among the three samples.The minimum genetic distances between these samples and those within Elaphe were greater than any currently recognized species within the genus.We conclude that this likely represents a new species within the genus Elaphe.Adult specimens and a morphologic description are needed for further study.
基金supported by the Korean Ministry of Environment as "The Eco-Technopia 21 Project(No.052-091-080)"
文摘The translocation of snakes has been viewed as a useful tool to augment declining populations and to mitigate human-wildlife conflicts, even though released snakes often exhibit relatively high mortality. We radio-tracked 13 Amur Ratsnakes （Elaphe schrenckii） in the Woraksan National Park in South Korea from July 2008 to May 2009. Two of these snakes were residents, and 11 had been illegally captured in areas remote from the study site and were donated by the park office. During the study period, six of the translocated snakes were lost： two were killed by predators, one died of unknown causes, and the radio signals of three of the snakes were lost. In the field, the ratsnakes laid eggs in early August, moved into hibemacula in late November, and moved away from the hibemacula in mid-April. Compared to the resident snakes, five of the translocated snakes traveled approximately 1.3 times farther per week, and the home ranges of the translocated snakes were three to six times larger than those of the resident snakes. In addition, the translocated snakes were found underground more frequently than the resident snakes. The management recommendations resulting from this study will guide biologists and land use managers in making appropriate decisions regarding release sites and the use of gravid females in the translocation of this endangered ratsnake.
基金supported by 2013 Research Grant(C100983401-01) from Kangwon National University
文摘In this report, we describe morphological characteristics of a dicephalic Steppes Ratsnake （Elaphe dione） collected from the wild in 2011 in South Korea. The specimen has two heads and two long necks. Unlike normal individuals, the dicephalic snake has divided ventral scales under the necks of the bifurcated columns. The snout- vent length （SVL） and overall total length of the individual are shorter than those of normal snakes of the same age. Nevertheless, the counts of nine different scale types that are often used for classification are all within the ranges of normal individuals. As far as we know, this is the first detailed morphological description of a dicephalic E. dione in the scientific literature.
基金supported by grants from Natural Science Foundation of China(31200283 and 31770443)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) of Jiangsu Higher Education Institutions。
文摘Research on the ecological effect of microronamentations on the scale surface in reptiles has been carried out over the past few decades.It is found that the microornamentation pattern in reptiles is related to their habitats.This study examined the wettability on scale surface,as well as the differences in microornamentation on ventral scales from the mid-body region in three snake species,Hypsiscopus plumbea(aquatic),Oocatochus rufodorsata(semi-aquatic) and Elaphe carinata(terricolous).Moreover,the scale specimens were metallized and analyzed using scanning electron microscopy.Our results showed that there are microornamentations on the ventral scale surfaces of the tested species,which showed interspecific differences.To be specific,the aquatic snake shows the narrow,fine and regular denticulations which are connected to reduce friction and dirt shedding.By contrast,the terrestrial snake acquired the wider and shorter denticulation which would render more friction during locomotion but it shows greater water resistance to improve the capacity of dirt shedding and compensate for the disadvantage of short and wide denticulations.Additionally,the denticulation characteristics of the semi-aquatic snake fell in between those of aquatic and terrestrial snakes.Therefore,it is deduced in this study that the ventral scale microornamentations in snakes contribute to ecological adaptation to their preferential microhabitats.
基金P.K.was supported by the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Grant[grant number:656006,project acronym:CoPhyMed]This work used the Vincent J.Coates Genomics Sequencing Laboratory at UC Berkeley,supported by NIH S10 OD018174 Instrumentation Grant.
文摘Comparing mitochondrial and genomic phylogenies is an essential tool for investigating speciation processes,because each genome carries different inheritance properties and evolutionary characteristics.Furthermore,mitonuclear discordance may arise from ecological adaptation,historic isolation,population size changes,and sex-biased dispersal.Closely related taxa are expected to experience gene flow;however,this may not be true for insular populations or populations isolated in refugia.The four-lined snake Elaphe quatuorlineata has a fragmented distribution,separating populations of the Italian and Balkan Peninsulas,whereas several insular Aegean populations of significantly smaller body size(Cyclades island group and Skyros Island,Greece)are currently considered distinct subspecies.We constructed the species-tree phylogeny of this species utilizing genome-wide single nucleotide polymorphisms and a gene-tree based on complete cytochrome b sequences,aiming to detect convergence and discrepancies between biparentally and maternally inherited genomes.Population structuring,phylogenetic patterns and migration events among geographically defined lineages supported our hypothesis of isolation in multiple sub-refugia.Where biogeographical barriers did not restrict subsequent dispersal,extensive genetic exchange occurred between mainland Balkan populations.This process has led to the mitochondrial sweep of an ancestral mitolineage that survived only in peripheral(East Greece)and insular populations(North Cyclades and Skyros).The Central Cyclades represent an ancient lineage for both molecular markers that emerged almost 3.3 Mya.Considering their distinct morphology,insular E.quatuorlineata populations should be the future focus of an extensive sampling,especially since the mitonuclear discordance observed in this species could be related to ecological adaptations,such as the island-dwarfism phenomenon.
