世界圆痕叶蝉亚科的系统发育和高级类群的修订

The leafhopper subfamily Megophthalminae comprises 772 described species currently placed in 63 genera. Megophthalmines feed on plant sap by the highly specialized piercing-sucking mouthparts. Some megophthalmine species are important agricultural pests which transmit plant pathogens. Despite the importance of these insects as a study group, there is no comprehensive phylogeny depicting the evolutionary relationships among these insects. Moreover, its higher classification is unstable and relationships among tribes and the natural relationships among the many megophthalmine genera are poorly understood. Based on our previous research on revision of Megophthalminae from the China and American region, this project will provide the first detailed phylogenetic analyses for this group and examine relationships within this lineage using a large number of morphological and anatomical information, DNA sequence data in combination with biogeographic data. Phylogenetic analysis of morphological and molecualr data will be used to inform decisions on the tribal placements of genera. Megophthalmine tribes and genera will also be redefined based on natural relationships. Moreover, a natural system of classification in conformity with the phylogenetic relationships and evolutional history will be built. This phylogeny will become the foundation for all future research on Cicadellidae, including the discovery and description of new species. In addition, the results from this research will allow scientists to better understand diversification of the group and biogeographical patterns at the continental and intracontinental level.

圆痕叶蝉亚科Megophthalminae昆虫刺吸植物汁液造成为害，许多种类传播植物病毒病，严重危害对农林生产。尽管圆痕叶蝉亚科的区系分类已取得一定进展，但整个亚科的系统发育关系仍然未知，高级分类单元分歧不断，族级阶元缺乏明确鉴别特征，许多属的鉴别特征之间广泛交叉与重叠，严重制约了圆痕叶蝉亚科昆虫分类和系统发育研究，亟待全面整合研究世界圆痕叶蝉代表性类群，重建系统发育，完成高级分类单元的重新划分和订正。本研究针对目前圆痕叶蝉分类存在的主要问题，在前期对中国及美洲地区圆痕叶蝉种类订正的基础上，综合形态和解剖学特征、生物地理和分子数据等特征，重建高级阶元的系统发育关系，廓清圆痕叶蝉亚科族、属等高级类群间及该亚科与近缘类群的亲缘关系，对族、属进行重新划分，构建反映自然进化历史的分类体系，为查清叶蝉科昆虫的种类及其分布格局、促进叶蝉科昆虫的分类研究提供理论基础。

圆痕叶蝉亚科分布于世界各地，但大多数族和属仅分布于单一地理区。该亚科昆虫刺吸汁液掠夺植物营养，许多种类传播植物病毒病，对农林生产造成严重危害。本项目通过广泛采集、调查，对世界圆痕叶蝉亚科进行了系统研究，建立了世界叶蝉亚科4族63属771种名录。对新北区、东洋区、澳洲区和古北区的种类进行了详细描述，完成了中国圆痕叶蝉亚科种类订正并编写中国动物志，包括3个新种、2个中国新记录种；开展了该亚科超微比较形态学研究，初步明确了圆痕叶蝉亚科昆虫的消化系统、生殖系统、精子的超微结构；口器和触角的形态及感器的类型、数量和分布。其中精巢的数量、生殖系统和消化系统的组成结构不同类群存在差异，精子长度、精核和附体形状、线粒体衍生物亚晶状区域可作为该类群的鉴别特征；不同类群口器和触角结构相似，感器的类型、位置及数量在不同属间存在差异。基于形态特征和分子数据结合，使用最大简约法、最大似然法、贝叶斯法进行了系统发育树的构建，支持圆痕叶蝉亚科为单系群，包括Agalliini, Adelungiini、Evansiolini和Megophthalmini4个族。圆痕叶蝉族Agalliini大多数属聚为一支，与其相似的生境相关，而且Agalliini 在新热带区极为丰富，而澳洲、非洲和马达加斯加种类稀少，表明圆痕叶蝉亚科起源于新热带区并后随泛古陆分离扩散至东半球，明确了该亚科高级类群的亲缘关系和划分。