The complete mitochondrial cytb gene and the partial nuclear c-mos gene of Oligodon ningshaanensis Yuan, 1983 were sequenced and used for reconstructing the phylogenetic relationship of this taxon amongst alethinophid...The complete mitochondrial cytb gene and the partial nuclear c-mos gene of Oligodon ningshaanensis Yuan, 1983 were sequenced and used for reconstructing the phylogenetic relationship of this taxon amongst alethinophidian snakes. Its strong affinity to the New World subfamily Dipsadinae and the Old World species Thermophis baileyi was inferred. Hemipenial morphology found by authors conflicts with the original description and its similarity with those of the dipsadid snakes is in accordance with our molecular results. Feeding tests show that O. ningshaanensis is a malacophagous predator, which is another matchless character for this species. This behavior is described and compared with other known slug- and snail-feeding snakes. The discovery of the particular position of our subject indicates that erecting a new genus is necessary accommodate this unique species.展开更多
Factors related to the invasion process, such as high abundance of invaders, residence time, and functional distinctiveness, are well documented, but less attention has been given to the effects of antipredator strate...Factors related to the invasion process, such as high abundance of invaders, residence time, and functional distinctiveness, are well documented, but less attention has been given to the effects of antipredator strategy of invasive species during colonization. In this study, we explored the antipredator strategy of an introduced species by comparing the predator avoidance behaviors of two native anuran species and one introduced （“exotic”） species in the presence of different predators. The two native anuran species used in the study were Black-spotted Pond FrogRana nigromaculata and Terrestrial Frog Rana limnocharis. The introduced （invasive） species used was American bullfrogLithobates catesbeianus. Chinese pond turtleChinemys reevesii, Red-backed rat snakeElaphe rufodorsata, and Big-headed turtle Platysternon megacephalum were used as predator species. Chinese pond turtles and Red-backed rat snakes are native predators of Black-spotted Pond Frogs and Terrestrial Frogs, while Big-headed turtles are novel （“unfamiliar”） to the two frogs. All three predator species are novel （“unfamiliar”） to the American bullfrog. The results show that tadpoles of the two native species displayed behaviors of recognizing the two native predators, but did not display the capability of identifying the novel predator. Results from our study also suggest that American bullfrog tadpoles exhibited strong antipredator behavioral responses by displaying the capability of identifying “unfamiliar” predators without cohabitation history and prior exposure to them. Such antipredator behavioral responses could have resulted in more favorable outcomes for an invading species during the invasive introductory process.展开更多
文摘The complete mitochondrial cytb gene and the partial nuclear c-mos gene of Oligodon ningshaanensis Yuan, 1983 were sequenced and used for reconstructing the phylogenetic relationship of this taxon amongst alethinophidian snakes. Its strong affinity to the New World subfamily Dipsadinae and the Old World species Thermophis baileyi was inferred. Hemipenial morphology found by authors conflicts with the original description and its similarity with those of the dipsadid snakes is in accordance with our molecular results. Feeding tests show that O. ningshaanensis is a malacophagous predator, which is another matchless character for this species. This behavior is described and compared with other known slug- and snail-feeding snakes. The discovery of the particular position of our subject indicates that erecting a new genus is necessary accommodate this unique species.
基金provided by the Doctor’s Start-up Foundation of Anhui Normal University and the National Natural Science Foundation of China
文摘Factors related to the invasion process, such as high abundance of invaders, residence time, and functional distinctiveness, are well documented, but less attention has been given to the effects of antipredator strategy of invasive species during colonization. In this study, we explored the antipredator strategy of an introduced species by comparing the predator avoidance behaviors of two native anuran species and one introduced （“exotic”） species in the presence of different predators. The two native anuran species used in the study were Black-spotted Pond FrogRana nigromaculata and Terrestrial Frog Rana limnocharis. The introduced （invasive） species used was American bullfrogLithobates catesbeianus. Chinese pond turtleChinemys reevesii, Red-backed rat snakeElaphe rufodorsata, and Big-headed turtle Platysternon megacephalum were used as predator species. Chinese pond turtles and Red-backed rat snakes are native predators of Black-spotted Pond Frogs and Terrestrial Frogs, while Big-headed turtles are novel （“unfamiliar”） to the two frogs. All three predator species are novel （“unfamiliar”） to the American bullfrog. The results show that tadpoles of the two native species displayed behaviors of recognizing the two native predators, but did not display the capability of identifying the novel predator. Results from our study also suggest that American bullfrog tadpoles exhibited strong antipredator behavioral responses by displaying the capability of identifying “unfamiliar” predators without cohabitation history and prior exposure to them. Such antipredator behavioral responses could have resulted in more favorable outcomes for an invading species during the invasive introductory process.
