基于线粒体全基因组的鳃虱科（甲壳动物亚门：等足目）系统发育研究

Family Bopyridae is the branchial or abdominal parasite infesting the important economic decapods, and it can impact on the growth,development and reproduction of the hosts, finally can harm the breeding of decapods. Nearly 20% of the bopyrids is in China,and many of them are endemic to China or Asia, but up to now parasitic life style of this group give rise to its morphological characteristic changable,asyngamy and difficult to collect. So the taxonomic system of family Bopyridae is confusion and few research about its phylogeny and coevolution. This study will select all subfamilies, 31 genera and 32 species of Bopyridae, and their complete mitochondrial genomes will be sequenced,then analysis and construct the phylogenetic relationsips on all subfamily and some representative genera of bopyrids, and determine the rank of the disputed species and genera in taxonomy, revise the original taxonomic system based on the morphological characteristics, explain the particular phenomenon which known from the taxonomic research; and compare and analysis the phylogenetic relationship between bopyrids and decapods, to explore the coevolution between them. The results will promote the completely research of order Isopoda, provide reference for some problems in decapods evolution, can also predict potential decapoda which may be infested by bopyrids, at the same time it will play a positive meaning for aquaculture disease prediction and control.

鳃虱科为重要经济十足目动物的鳃腔或腹部寄生物，其寄生可对寄主的生长、发育和繁殖产生很大的影响，为虾蟹等十足目养殖业带来一定的危害。世界近20%的鳃虱分布在中国各大海域，不少种类为中国或亚洲特有。但目前该类群因寄生而导致物种鉴定所依据的形态特征变化较大，雌雄异形，加上标本采集较困难，所以导致鳃虱科现有的分类系统比较混乱，系统演化、协同进化方面的研究工作几乎没有开展。本研究将通过鳃虱科全部亚科31属32种的线粒体基因组全序列测定，分析鳃虱科内部所有亚科间、代表性属间系统发育关系；确定分类学上有争议的种、属的准确地位，修订原有依据形态特征建立的分类系统，解释形态分类学研究中发现的特殊现象；探讨鳃虱科与十足目寄主之间的协同进化关系。研究结果将促进等足目类群的整体研究，同时为其十足目寄主演化中的一些难以解决的问题提供借鉴，也可预测十足目可能的被寄生类群，对水产养殖病害预测与防治起到积极的意义。

项目组利用线粒体基因组数据对等足目鳃虱科的分类、系统发育关系进行了系统地研究。鳃虱科物种是重要经济十足目动物的鳃腔或腹部寄生物，可影响寄主的生长、发育和繁殖，为虾蟹等经济甲壳动物的养殖带来一定的危害。项目组对采自中国及周边海域的标本进行整理鉴定，首先通过形态学特征鉴定，绘图，共鉴定鳃虱科52种，属于7亚科，建立新属5个，发现22个新种，在此基础上，理清了中国海域鳃虱科物种，发现包括香港、台湾在内共124种鳃虱。然后，选择具有代表性物种进行了线粒体基因组测序分析，分析了所有物种的基因组结构组成、tRNA二级结构、基因间隔、重叠、缺失情况。依据序列数据对鳃虱科内部分属、种的分类地位进行了修订，确定了分类学上有争议的种、属的准确地位，明确了祖征和衍征。基本搞清了鳃虱科内部各亚科之间的系统演化关系，重新确立了寄生亚目的分类地位；证明了假鳃虱亚科的单系性不成立；而对虾鳃虱亚科的单系性得到了证实；也验证了假鳃虱亚科与蟹鳃虱亚科之间的亲缘关系；否定了基于形态特征推测的真腹虱亚科的演化地位；证实了褐虾鳃虱亚科与真腹虱亚科之间较近的亲缘关系；解决了形态学上一直未有定论的拟对虾鳃虱属与仿拟对虾鳃虱属之间很近亲缘关系。研究结果对促进等足目类群的整体研究，和寄主十足目的演化研究提供了借鉴，对水产养殖病害预测与防治起到积极的意义。