中国耳草属(广义)植物的分类修订

Hedyotis s.l. belongs to the tribe Spermacoceae of the family Rubiaceae. It included about 600 species worldwide and distributed broadly but with high endemism. In China, there are about 75 species, taking up approximately 50% of the total Asian Hedyotis species. Many previous studies showed the taxonomic confusion and dispute over the genus has been existing since it was established in 1753. Moreover, many taxonomic nomenclature, type designation, morphological description, species delimitation criteria, etc. are also involved in this genus. On basis of our previous preliminary work, the present project will begin by literature consultant, field investigation, herbarium specimen examination and population observation and analysis, and combine the morphological, palynological and flora developmental observation methods and molecular DNA barcoding technique, so as to clarify the confusion of the type status and morphological description, reveal the morphological character of the type specimen and the population variation pattern of each species, especially the complex species. Under this circumstance, the comprehensive analysis to the above data will help define the principle and criteria of species delimitation so that we can apply them to deal with the taxonomic problems and finish the taxonomic revision of Chinese Hedyotis species. The results derived from this project will play an important role in not only understanding of the species biodiversity of Hedyotis in China but also can provide important materials for further study on the phylogenetic analysis and biogeography in future. In addition, it can be a solid basis for expanding the work to the adjacent regions.

广义耳草属隶属茜草科钮扣草族，全世界约600种，分布广泛且特有性高。我国目前有耳草属植物75种，约占亚洲地区总数的一半。本属植物的分类学问题从其1753年创立至今就一直存在争论，并且本属物种的命名、模式指定、形态描述、物种划分等也存在着许多问题。本项目在前人对耳草属分类研究的基础上，拟通过文献资料整理、标本查阅测量、野外调查采集等工作，结合形态学、孢粉学、花发育等特征观察方法和DNA条形码技术，以澄清耳草属种类在模式状态和特征描述方面存在的混乱，揭示每个物种（特别是复合群）的居群变异式样。在综合分析以上数据的基础上，确定物种划分的原则和标准，从而解决我国广义耳草属的分类学问题并完成其分类学修订。本项目成果可为全面了解我国广义耳草属植物的物种多样性、深入开展耳草属植物的系统发育和生物地理等提供重要的研究材料，并为进一步拓展对周边国家相关类群的研究奠定基础。

广义耳草属（Hedyotis s. l.）是茜草科最大的类群之一，广泛分布于全球热带与亚热带地区。我国是耳草属植物分布中心，曾记载有70余种。本项目研究人员查阅了国内外10余个标本馆有关中国和东南亚地区1600多份模式标本和5600多分本属其它植物标本，调查和采集了240余个野外居群，观察了30种1变种的叶表皮和50种2变种的种子微形态，建立了耳草属植物数据库，拍摄了大量的植物照片，对广义耳草属的形态性状及其变异幅度进行了系统研究，重新评价了各性状的分类学价值。目前共发表研究论文13篇，包括台山耳草Hedyotis taishanensis、铜鼓岭耳草H. tonggulingensis、毛叶耳草H. puberulifolia、毛茎耳草H. pubirachis、宽昭耳草H. howii、断节耳草 H. interrupta、短柄藤耳草Dimetia brevipetiolata、石生耳草Involucrella lithophila等8个新种；合叶耳草属 Parainvolucrella一个新属；记录了小耳草H. pumila在我国的新分布；修订了长期误用的纤花耳草 Hedyotis tenelliflora 学名；归并了Hedyotis dinganensis、H. bodinieri, H. assimilis, H. mellii，H. shiuyingiae 等5个分类学异名；提出一个保留学名H. caudatifolia等。本研究结果支持将广义耳草属植物分为Dimetia、Debia、Hedyotis s. str.、Involucrella、Leptopetalum、Oldenlandia s. str.、Oldenlandiopsis、Parainvolucrella和Scleromitrion等9个小属。另外，项目主持人还开展的国际合作，参与了新加坡植物志中有关耳草属的编写。初步统计表明，目前我国耳草属植物已达93种，为目前亚洲地区种类最多的国家。通过项目的开展，培养了3名硕士研究生，并有3名研究助理和1名博士生得到了分类学的培训。项目研究成果对于开展分子系统学和生物地理学研究，以及开展植物多样性保护等具有重要的意义。