Lyu Zhangxia, Cheng Jiaoni, Shao Jingru, Ye Qingqing, Bai Huixian, Wen Jianfan
State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, 650223, China.
Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, 650204, China.
Int J Parasitol Parasites Wildl. 2020 Apr 28;12:46-52. doi: 10.1016/j.ijppaw.2020.04.009. eCollection 2020 Aug.
is a species which is morphological distinguishable for its very narrow and elongated trophozoite. Although there were a few studies about its morphology since its first report in 1882, none investigations about its prevalence have ever been reported to date. We investigated the prevalence of in 25 anuran amphibian species from five provinces of China using both morphological and molecular methods. Of the 463 tested samples, 195 (42.1%) were positive. The 195 positive samples were from nine species, which are scatteredly distributed in four anuran amphibian families. The statistical prevalence among adults of different frog species showed no significant difference, and so did among tadpoles. Thus, is probably able to infect all anuran amphibians without species-bias. More interestingly, the prevalence in the tadpoles is significantly higher than in their adults. The prevalence in tadpoles from the same area showed no significant differences between none-legged stage and two-legged stage, but the prevalence in these two developmental stages is significantly higher than in the four-legged stage. And the prevalence in four-legged stage is still much higher than in adults. A turning point of prevalence appeared in the period of tadpole tail degeneration. Moreover, all the positive samples were from the areas with relatively high altitude (more than 870 m). The fact that tends to easily infect the frogs living in high altitude areas indicated it has evolved the ability to adapted the dramatic temperature change in poikilothermal animals. Therefore, has evolved some special successful parasitism strategies for parasitizing the poikilothermal hosts with metamorphosis such as anuran amphibians.
是一种因其极窄且细长的滋养体在形态上易于区分的物种。尽管自1882年首次报道以来有一些关于其形态学的研究，但迄今为止尚无关于其流行情况的调查报道。我们使用形态学和分子方法调查了中国五个省份25种无尾两栖动物中的流行情况。在463个测试样本中，195个（42.1%）呈阳性。这195个阳性样本来自9个物种，它们分散分布在四个无尾两栖动物科中。不同蛙类成年个体中的统计流行率没有显著差异，蝌蚪中的情况也是如此。因此，可能能够无物种偏向地感染所有无尾两栖动物。更有趣的是，蝌蚪中的流行率显著高于成年个体。来自同一地区的蝌蚪在无腿阶段和两条腿阶段之间的流行率没有显著差异，但这两个发育阶段的流行率显著高于四条腿阶段。并且四条腿阶段的流行率仍然远高于成年个体。在蝌蚪尾巴退化时期出现了流行率的转折点。此外，所有阳性样本均来自海拔相对较高（超过870米）的地区。倾向于容易感染生活在高海拔地区青蛙的这一事实表明它已经进化出适应变温动物剧烈温度变化的能力。因此，已经进化出一些特殊且成功的寄生策略来寄生于诸如无尾两栖动物这种具有变态发育的变温宿主。
