Department of Biological Sciences, Auburn University, Auburn, Alabama, United States of America.
US Geological Survey, Fort Collins, Colorado, United States of America.
PLoS One. 2019 Jan 2;14(1):e0209252. doi: 10.1371/journal.pone.0209252. eCollection 2019.
Invasive Burmese pythons (Python bivittatus Kuhl, 1820) have introduced a lung parasite, Raillietiella orientalis, (Hett, 1915) from the python's native range in Southeast Asia to its introduced range in Florida, where parasite spillover from pythons to two families and eight genera of native snakes has occurred. Because these novel host species present a diversity of ecological and morphological traits, and because these parasites attach to their hosts with hooks located on their cephalothorax, we predicted that R. orientalis would exhibit substantial, host-associated phenotypic plasticity in cephalothorax shape. Indeed, geometric morphometric analyses of 39 parasites from five host species revealed significant variation among host taxa in R. orientalis cephalothorax shape. We observed differences associated with host ecology, where parasites from semi-aquatic and aquatic snakes exhibited the greatest morphological similarity. Morphological analyses of R. orientalis recovered from invasive pythons, native pit vipers, and terrestrial snakes each revealed distinct shapes. Our results suggest R. orientalis can exhibit significant differences in morphology based upon host species infected, and this plasticity may facilitate infection with this non-native parasite in a wide array of novel squamate host species.
入侵的缅甸蟒（Python bivittatus Kuhl，1820）从其原生范围东南亚引入了一种肺寄生虫，东方片形吸虫（Raillietiella orientalis）（Hett，1915），到其引入的佛罗里达州，寄生虫从蟒蛇溢出到两种科和八种属的本地蛇类。由于这些新的宿主物种具有多样性的生态和形态特征，并且这些寄生虫通过位于其胸甲上的钩子附着在宿主身上，我们预测东方片形吸虫在胸甲形状上会表现出显著的、与宿主相关的表型可塑性。事实上，对来自五个宿主物种的 39 个寄生虫的几何形态计量学分析表明，东方片形吸虫的胸甲形状在宿主分类群之间存在显著差异。我们观察到与宿主生态相关的差异，其中来自半水生和水生蛇类的寄生虫表现出最大的形态相似性。从入侵的蟒蛇、本地响尾蛇和陆地蛇中回收的东方片形吸虫的形态分析揭示了不同的形状。我们的研究结果表明，东方片形吸虫可以根据感染的宿主物种表现出显著的形态差异，这种可塑性可能有助于这种非本地寄生虫感染广泛的新型蜥蜴目宿主物种。
