兰科舌唇兰属约有150-200种，主要分布在亚洲、北美洲和欧洲，部分种类分布到非洲北部和中美洲。亚洲是舌唇兰属多样性中心，分布约100-150种，大部分种类为其特有种。 . 目前的分子系统学研究表明，广义舌唇兰属为单系类群，但由于形态特征变异复杂，同时缺乏系统性分类修订和系统学研究，舌唇兰属物种的划分比较混乱，属内关系不清。. 本项目计划通过分子系统学等方面的证据，重建舌唇兰属的系统发育关系, 在系统发育框架下，揭示宏观和微观形态性状、细胞核型、传粉系统等的变异规律，评估各性状的分类学价值；在此基础上, 综合各种分类证据，兼顾相似性、单系、进化、名称稳定等分类原则，开展亚洲舌唇兰属的综合分类学研究，进行分类修订工作，厘清种间的界限，并探讨属下各类群间亲缘关系和进行属下系统划分。本项目将为舌唇兰属植物的生物地理学、保护生物学、进化生物学等研究奠定基础。

Platanthera s.l. (Orchidaceae, Orchioideae) comprises about 150-200 species, mainly distributed in Asia, Europe, and North America, with a few species extending into North Africa and Middle America. There are about 100-150 species in Asia, out of which most are endemic in Asia..Previous results of molecular systematics indicated that Platanthera s.l. is monophyletic, however, species delimitation and phylogeny within Platanthera are confusing due to the complicated variation pattern of morphological characters of Platanthera, together with the absence of taxonomic revision and phylogeny at generic level.. The aims of this project are to 1) take a taxonomic revision of Platanthera from Asia, and 2) understand the phylogeny within Platanthera. We will reconstruct the phylogeny of Platanthera based on molecular systematics, then evaluate variation patterns of characters, including karyotype, macro- and micromorphological characters, and pollination biology. An integrative revision of Platanthera from Asia will be taked based on above mentioned evidence and the principles of taxonomy, including similarity, monophyly, evolutionary pattern and the stability of nomenclature. Phylogeny within Platanthera will be discussed and a new infrageneric system of Platanthera will be provided. The results of this study will have substantial effects on the conservation biology, evolutionary biology and biogeogarphy of Platanthera.