东亚扁蜂科系统分类研究

Pamphiliidae is a basal lineage of Symphyta, Hymenoptera, with a peculiar morphological character: head with four opennings which is ifferent from all ther taxa of Hymenoptera that the head has only one or two opennings. The family is endemic to Holarctic region and all species feed on Coniferae and basal lineage of angiosperm plants. Some species of the family are widely-distributed, multiple and important forest pests of boreal forest in north hemisphere. Till present about 365 species belonging to 11 genera have been described in the family in the world wide. Among them 9 genera and 121 species have already been recorded from China and most of them are endemic to China. Except for some countries of E. Asia region, the pamphiliidae fauna of world has been well surveyed. However, transnational revision of the family, the phylogenetic analysis and biogeographic researches on the family are still in empty. According to the preliminary research on the material of world famous sawfly collections including Smithsonian Institute (USA), the National Museum of Natural History of Great Britain, the entomological Institute of Germany, the Chinese Academy of Forestry, the sawfly collection of Central South University of Forestry and Technology, etc., it is confirmed that there are at least 200 species of the Pamphiliidae in China and not less than 260 species in eastern Asia. It seems quite probably that the eastern part of China is the main distribution centre and differentiation centre of the family. This project is aimed at to research the morphological and molecular phylogeny of the family, to revise the eastern Asian species of Pamphiliidae, to reconstruct the phylogeny of Pamphiliidae, to probe into the biogeography of the family and the coevolution relationship between Pamphiliidae and their host plants, and at last to deduce the possible evolution process of the eastern Asian fauna of the family. The research has important bearing on the systematic entomology and biogeography, and it is also important in the practice of the biodiversity conservation and control of forest pests in east asian region.

扁蜂科是全北界特有的植食性类群，全部以裸子植物的松柏类和低等被子植物为食，部分种类是北半球温带森林的重要广布性多发害虫。全世界已知11属365种，东亚地区记载9属217种，中国已发现9属121种,其中多为中国特有种类。除东亚部分区域外，此科昆虫的区域性系统分类学已有较好的研究基础，但跨区域物种厘订、类群系谱发生和分子分类以及生物地理研究等方面尚属空白。根据申请者的初步研究，中国扁蜂种类不少于200种，东亚地区不少于260种，推测亚洲东部是本类群的主要分布中心和分化中心之一。本项课题拟通过系统研究扁蜂科比较形态学和分子系统学，探讨扁蜂科与其他叶蜂类群间的系统演化关系和科内属种间关系，推断本科东亚区系的可能形成过程，厘订东亚种类。此项研究在昆虫系统学领域和生物地理学领域具有较重要的理论意义，在生物多样性保护和森林害虫控制领域也具有一定的意义。

扁蜂科是全北界特有的植食性类群，全部以裸子植物的松柏类和低等被子植物为食，部分种类是北半球温带森林的重要广布性多发害虫。全世界已知11属370种，东亚地区记载9属230种，中国已发现9属123种，其中多为中国特有种类。亚洲东部是本类群的主要分布中心和主要分化中心之一，但与其他区域相比，本区域的扁蜂系统分类学基础最弱。本项课题执行前本科的类群系谱发生和分子分类等方面的研究尚属空白。. 本项课题的主要研究内容是：1 基于形态的扁蜂科系统发育研究；2 基于线粒体基因组的扁蜂科系统发育研究；3 扁蜂科生物地理初步研究；4 东亚部分扁蜂类群分类厘订研究。. 重要研究结果：1 确认了扁蜂总科（扁蜂科+广蜂科）的单系性，确认扁蜂总科支系是膜翅目基部的第2个干支系；2 确认扁蜂科是单系群，广蜂科是其姊妹群；3 确认扁蜂科内扁蜂亚科和腮扁蜂亚科的双亚科分类系统是自然的，各自都是单系群；4 发现在现有的11属分类系统中，种类最多的4个属中，Onycholyda属是Pamphilius属的内群，Acantholyda是Cephalcia的内群，Pamphilius和Cephalcia两属的单系性存疑；新进发现的Chrysolyda Shinohara 2002也可能是Pamphilius属的内群。5 完成了扁蜂科7属15种的线粒体全基因组测序和分析，发现了扁蜂科线粒体基因组的一些主要特征；6 完成了扁蜂总科5属6种核基因组测序和分析，重建了扁蜂总科系统发育关系；7 完成了东亚扁蜂科部分类群的分类厘定研究；发现东亚扁蜂科其他类群新种25种；基于幼虫的分子鉴定，确认了2个异名关系；8 基于分子系统学研究和分子生物地理研究，初步判断扁蜂科的起源地为东北亚地区，其干支系的起源时间在距今1.64-1.65亿年之间，冠群的主要分化时间在距今31.9百万年至2.2百万年之间。而扁蜂总科干支系的起点时间推断在2.0-2.3亿年前。. 此项研究在昆虫系统学领域和生物地理学领域具有较重要的理论意义，在生物多样性保护和森林害虫控制领域也具有一定的意义。