世界蕨藓科的分类修订及分子系统学研究

Pterobryaceae is an important representative group of tropical mosses and its system position is in Hypnales. It’s a rapid differentiation group which includes about 170 species in 24 genera. The tropical and subtropical regions of the world is its main distribution. Since its establishment in 1897, the system position and the subfamily group of Pterobryaceae have undergone many changes. However, there are still many problems: (1) the definition of family is not perfect. Its unique definition character is lack, and the relationships among it and the related families are not clear. (2) The system position of the genera are uncertain, and some of the genera maybe not belong to Pterobryaceae. (3) The concept of some genera and the boundary among genera are unclear, for the confusion among the genera and the lack of research. (4) The relationships among some species in several genera are not clear.. In response to the above problems, this project intends to take morphological taxonomy and molecular systematics studies to complete the revision of the problem genera, and to verify the systematic position of the genera. According to the morphological and molecular data, we will give a new circumscription of the family and the genera, and give a perfect taxonomic treatments on the genera.

蕨藓科是热带藓类植物的重要代表类群，现位于灰藓目，是灰藓目中快速分化出来的一支，也是较为进化的藓类植物。该科现有24属，约170种，主要分布在全球的热带及亚热带地区。自1897年建立至今，蕨藓科的系统位置及科下类群都经历了大的变革，但在科属种等各个阶元仍然存在许多的问题：(1)科的界定不完善，其特有的分类特征缺乏，与邻近科的系统关系不明确。(2)属的系统位置不确定，部分属不能确定是否属于蕨藓科，属间系统关系无人研究。(3)属的概念及属间界限不清楚，部分属的概念存在交叉。(4)部分属种类划分不清楚。. 针对上述问题，本项目拟采取形态分类学和分子系统学研究，对有问题的属进行系统地世界分类修订研究。同时，综合两方面数据，对科和属的系统位置及属的自然性进行验证，得出蕨藓科的定义，对科下类群及各个属下阶元进行合理界定。

课题聚焦热带重要藓类植物蕨藓科，利用分类形态学和分子系统学的手段解决该科科、属、种多个层级的分类学和系统学问题。主要有以下研究进展。. (1)完成了蕨藓科耳平藓属、拟蕨藓属、Henicodium，亚洲兜叶藓属、瓢叶藓属和Symphysodon 6个属的分类研究。明确了属的概念和属下阶元的界定。 (2)对系统关系混乱的属重新理清关系，进行准确界定，主要有耳平藓属和拟蕨藓属、兜叶藓属和Cryptogonium。证实了拟蕨藓属不是单系，分为3支，建立2个新属。 (3)通过分子和形态证据，确定蕨藓科为单系，自然独立的类群。确认存疑的Henicoldium隶属于蕨藓科；山地藓属归入蔓藓科；利用细胞器基因组构建系统发育树，理清了蕨藓科和平藓科的系统关系，两者为独立的分支。将蕨藓科滇蕨藓归入平藓科；隐蒴藓科的毛枝藓属的部分类群归入蕨藓科。 (4)在检视标本的过程中，发现中国新纪录属一个Jaegerina和3个中国新纪录种。. 研究结果对于后续研究热带植物的演化和分化，生物地理分布形成原因等都提供了最基础的本底数据。