中国缟蝇亚科疑难属的分类订正和系统发育研究

Lauxaniidae is an important ecological and economic group as an indicator of the enviromental changes in ghe ecological system of land. Adults and larvae are recorded as fungal grazers and detritovores in leaf litter, decaying vegetation and birds’ nests. Some of them visit flowers and benefit to plant pollination. A few of larvae were found on the dead animals, with the potential value of forensic insects. China is one of the richest countries with generic and specific diversity and habitat diversity of Lauxaniinae (Diptera, Lauxaniidae) in the world. There are more than 1200 species 132 genera in the world and more than 100 species 28 genera in China. The aim of this project is to revise the known genera and species, especially doubtful genera and species, describe and record new genera and species; to infer the phylogeny of the subfamily Lauxaniinae and discuss the relationship of genera and subgenera by analyzing the morphological characters, the nucleotide sequences of 28SrDNA, EF-1ɑ and the mitochondrial gene sequences of 16SrRNA, COI; to solve the confusion and difficulties of morphological identification; to clarify the monophyly or paraphyly of Lauxaniinae; then to build and improve Taxonomy of Lauxaniinae. This would enhance diversity of Lauxaniidae, develop further study of phylogeny and evolution on Lauxanioidea. It is an importnant and necessary to protect and utilize the diversity of the lauxaniids in China.

缟蝇科成、幼虫主要为腐食性和菌食性，对生态环境变化敏感，是陆生生境变化评价的指示生物之一；部分属的成虫可访花，有助于植物传粉；少数种类的幼虫被发现于动物尸体上，有潜在的法医昆虫应用价值。我国缟蝇亚科昆虫资源丰富，生境多样化，是世界缟蝇科区系研究的重要组成部分。缟蝇亚科世界已知132属1200余种，我国已知28属100余种。本项目拟对我国已知属、种，特别是疑难属种(存在种类归属、归亚属问题)进行系统的分类修订，发现和描记新纪录属、种；联合外部形态数据和基于28SrDNA、EF-1ɑ、16SrRNA和COI基因序列的分子数据，构建缟蝇亚科的系统发育树，探讨不同属间(特别是疑难属种)的关系，解决形态分类鉴定的难题，建立和完善中国缟蝇亚科的分类系统。该研究结果将大大丰富缟蝇科的物种多样性，为进一步探讨缟蝇亚科的单系性和缟蝇总科的分子系统学研究奠定基础，也对加强我国缟蝇科昆虫资源保护有重要的意义

缟蝇科成、幼虫主要为腐食性和菌食性，对生态环境变化敏感；部分属的成虫可访花，有助于植物传粉。缟蝇亚科昆虫世界已知132属1200余种，我国已知28属100余种。本项研究采用外部形态特征和雌雄外生殖器比较的方法，记述了我国缟蝇亚科14属103个新种、6个新纪录种，修订了9个已知种；缟蝇亚科不同属的种类雄性外生殖器结构的变异较大，通过对14属120种的形态学研究，比较了14属（亚属）间种的雄性外生殖器结构，找出相对应的退化的或发育完全的具体部位，奠定了利用形态特征数据推测疑难属间系统演化关系的基础。选取缟蝇亚科18属39种51个形态特征，探讨了基于形态特征数据的不同属间系统发育关系，特别是对疑难属Minettia、Calliopum、Sapromyza、Noeetomima属、Melanoachycerina属、Protrigonometopus属、Trigonometopsis属的形态特征进行了深入分析，且联合核糖体28SrDNA和EF-1ɑ、线粒体16SrDNA、12SrDNA和COI基因序列的比对、分析，构建了缟蝇亚科18属42种的支序图，综合形态和分子数据两方面分析了属间系统发育关系；首次整合形态特征和分子数据，解决了部分疑难属物种形态分类鉴定的瓶颈问题，为我国缟蝇科昆虫资源的保护，及其在环境监测、植物传粉、法医昆虫学等方面的潜在应用提供了物种鉴别基础；本项研究也表明，我国缟蝇亚科属、种丰富，生境多样，具有潜在的环境指示生物的应用价值。这需要针对不同生境，选取优势种，开展更进一步验证。