云南鱼类单殖吸虫的种类组成、宿主特异性及其系统发育研究

In view of the host specificity and coevolution between Monogenea-fish associations, Monogenea present strikingly special relationship and idealized experimental paradigm in the field of origin and development of parasitism. The molecular phylogeny of Monogenea leads to new insights on the origins of their early vertebrate hosts while simultaneously phylogenetic relationships of hosts were reconstructed and inferred from the phylogeny of their monogenic flatworms based on genetic molecular data. The biodiversity of class Monogenea are widely diverse with their host fishes of Yunnan Province,where has repeatedly been ranked high in terms of species diversity, such as endemicity and indigene species fishes. Endemically distributed species can better represent the characteristics of fauna and inital radiation and coevolution with Monogenea-fish associations. The present application focus on monogenic flatworms that parasitic in fishes of Yunnan Province. New species and composition will be discribed by numerical taxonomy methods according to morphologic characters. The level of host-parasite specificy and characteristics of fauna will be ascertained.Phylogenies of host and parasite between genera will be indicated from genetic molecular data of 18S rRNA ITS1 gene sequences to examine host-parasite coevolution. The basal research application will enrich the fauna sinica platyhelminthes, and adequately reveal the unique biodiversity and superiority of geographical district of Yunnan province.The research will provide a potent exemplification of southeastern Asian to primarily demonstrate the mechanism of historical biogeography and coevolution of Monogenea-fish associations. The data of molecular phylogeny will distinctively infer the long-standing coevolution relationship between fish and monogenic parasite.

宿主特异性及协同进化使单殖吸虫成为研究寄生现象起源和发展、寄生虫与宿主协同进化理想的实验范例。单殖吸虫分子系统发育研究为揭示和重建脊椎动物宿主的系统起源进化提供了新颖的视角。云南具有丰富的鱼类及单殖吸虫多样性，地方性分布的鱼类、土著鱼类单殖吸虫对于揭示寄生虫和宿主的协同进化具有有别于我国其他区系的独特性。本项目调查研究云南鱼类寄生单殖吸虫本底资源及分布情况，明确云南鱼类单殖吸虫的种类组成、宿主特异性及其区系特征；基于rDNA（ITS1或28S rDNA）序列重建系统发育，揭示鱼类-单殖吸虫协同进化关系。该研究虽属于基础理论研究范畴，但研究成果将对吸虫志做出重要补充，充分体现云南地理区位所致的物种多样性优势，为单殖吸虫系统发生呈现东南亚（中国）的进化世系证据，为进一步揭示寄生虫与宿主之间的协同进化提供新的、必不可少的研究例证，具有重要学术意义。

宿主特异性及协同进化使单殖吸虫成为研究寄生现象起源和发展、寄生虫与宿主协同进化理想的实验范例。单殖吸虫分子系统发育研究为揭示和重建脊椎动物宿主的系统起源进化提供了新颖的视角。云南具有丰富的鱼类及单殖吸虫多样性，地方性分布的鱼类、土著鱼类单殖吸虫对于揭示寄生虫和宿主的协同进化具有有别于我国其他区系的独特性。本项目调查研究了云南鱼类寄生单殖吸虫本底资源及分布情况，明确云南鱼类单殖吸虫的种类组成、宿主特异性；基于rDNA序列重建系统发育，揭示鱼类-单殖吸虫协同进化关系。.研究中共采集或购买鱼类标本目11科49种共1986尾。从鲤鱼、麦穗鱼、䱗条、马口鱼、子陵吻鰕虎、罗非鱼、奇额墨头鱼、棒花鱼、短吻鱼、黄颡鱼等19种鱼类鳃片上检获单殖吸虫4科12属56种，其中已记录种32种，未定种19种，新种5种，云南分布新纪录15种，宿主新记录种7种。多钩亚纲指环虫目指环虫科指环虫属38种，多基虫属1种；锚首虫科锚首虫属1种，伪锚盘虫属1种，副似锚首虫属1种，四锚虫属 1种，嗜丽鱼虫属6种，盾形片虫属1种，鯰盘虫属2种。三代虫目三代虫科薄片吸虫属1种。寡钩亚纲铗盘虫目双身虫科真双生虫属1种、拟双身虫2种。.基于ITS 2基因序列的遗传学特征及双身虫科系统进化树，经形态学分类鉴定的双身虫科拟双身虫属新种，云南拟双身虫聚在了拟双身虫属clade上，且位于拟双身虫属clade的基部，佐证了形态学鉴定的结果，即新种云南拟双身虫成立。基于28S rDNA序列重建了锚首虫科嗜丽鱼虫属和盾形片虫属的系统进化树，两属分别聚为不同的进化分枝，形态学分类与分子鉴定所呈现分类地位的互为映证。