小头虫亚目分类学性状及中国海物种多样性研究

Capitelliformia belongs to class Polychaeta, phylum Annelida, and represents one of the most frequently encountered group in offshore waters. Some members of this goup have been traditionally regarded as bioindicator. Although there are a certain number of taxonomic studies on this group, little information can be available for the validity of some taxonomic characters for distinguishing genera and species, scientific ultilization of the taxonomic characters, and Chineses species compostition. In this study, a series of study methods, including morphological methods, anatomical methods, molecular biology techniques and statistical methods are ultilized. We firstly study the taxonomic characters that commonly used, including the variation and mechanisms of certain characters (such as hooded hooks) during the ontogeny, the diversity of representation of typical characters (cleavage characters, ordered polymorphism characters and quantitative characters) and the mechanism of their variations, the discovery of new taxonomic characters based on the methods such as staining, anatomy and statistic analysis of data. Secondly, Cluster analyses are performed based on data sets which are composed of morphological characters. The conclusion of species identification is made mainly based on the results of clusters, and sometimes with the supplement of DNA segment information when needed. Thirdly, a revision of Chinese Capitelliformia species is conducted, including those are numerically dominant, but perhaps have been misidentified for a long time, and those have been recorded without sufficient taxonomic information, the description of new species and new recorded species from Chinese seas. The all studied species, including their taxonomic characters, distribution patterns, ecological characteristics are excepted to be invovled in a database. This work is expected to enhance our current knowledge of the taxonomy, species diversity of Capitelliformia and ultilization of marine biological resources.

小头虫亚目（Capitelliformia）在近海水域兼具数量优势和环境指示功能，是环节动物门多毛纲中的“明星类群”。虽该类群研究基础较好，但仍存在部分重要的基础分类学问题亟需解决。本项目针对其中的分类学性状和西北太平洋中国海沿岸物种多样性两方面问题，运用形态学、解剖学、分子生物学和统计学等手段，探讨目前常见性状（两元性状、有序多态性状和数量性状）表征的多态性及其决定机制，特定性状在个体发育过程中的变化规律；建立以形态学性状聚类结果为主、分子序列信息为辅的种类鉴定方法；确定中国海可能存在的隐存种；修订中国海种类组成，包括新（记录）种的记述、确有文献记载但未有充分分类学信息种类的补充研究、近海优势度较高但可能被错误记录种类的重新鉴定；构建包括种类、分类学性状、区系特征和生态习性等信息的数据库。项目的开展可推动小头虫亚目分类学和生物多样性研究，还可为我国海洋生物资源保护和利用研究提供理论基础。

小头虫亚目（Capitelliformia）在近海水域兼具数量优势和环境指示功能，是环节动物门多毛纲中的“明星类群”。虽该类群研究基础较好，但仍存在部分重要的基础分类学问题亟需解决。本项目针对其中的分类学性状和西北太平洋中国海沿岸物种多样性两方面问题，运用形态学、解剖学、分子生物学和统计学等手段开展了相关研究。研究共鉴定小头虫亚目4科16属29种（包括8种尚未鉴定至种级水平的物种），对各鉴定物种进行了较为详细的形态学观察和分类学描述，对物种的生态学特征和地理区系特点也进行了较为全面的讨论。探讨目前2种常见性状（巾钩刚毛形状和数量）表征的多态性，明确了巾钩刚毛的形状在小头虫科物种中具有较高的稳定性，但巾钩刚毛的数量在种内具有较大的变异性，巾钩刚毛的数量不宜作为物种鉴定的主要鉴别特征；建立以形态学性状聚类结果为主、分子序列信息为辅的种类鉴定方法，明确小头虫种和其中的两型在分子特征上未有显著的差异。综合上述研究结论，本研究较为系统地修订中国海种类组成，包括新（记录）种的记述、确有文献记载但未有充分分类学信息种类的补充研究、近海优势度较高但可能被错误记录种类的重新鉴定。项目的开展可推动小头虫亚目分类学和生物多样性研究，还可为我国海洋生物资源保护和利用研究提供理论基础。