中国金星介亚目介形类分类及系统发育研究

Ostracods are one of the most diverse groups of living crustaceans, inhabition marine, non-marine and even some semi-terrestrial habitats. The number of living ostracods is estimated to be more than 20,000, of which approximately 8,000 have been described. But living ostracods are still poorly understood in China and in urgent need of taxonomic. More than 160 living species of suborder Cypridocopina have been reported in China, and the suborder is one of the most taxonomically difficult groups among ten suborders of Ostracoda because of error identification (including synonym and homonym), and unscientific classification and ambiguous phylogenetic relationships. Thus, a taxonomic revision of suborder Cypridocopina is urgent and necessary in China. On the basis of our previous work on non-marine ostracods, our project is to collect a sufficient quantity of samples of Cypridocopina to study morphology and distribution of every species by the methods of classical animal taxonomy, and we will have a clear knowledge of species number and distribution in China. Moreover, new checklist of suborder Cypridocopina will be compiled in China and both morphological image and anatomic drawing of every species will be provided. Because the methods of phylogenetic studies are legitimate and supplement each other. Based both on our own research and on our extensive reading of the literature, we will try to select some appropriate morphological and molecular characters to explore phylogenetic relationship in suborder Cypridocopina by the methods of both cladistic and molecular phylogenetic analysis. Finally, a classification system of suborder Cypridocopina will be created based on our results from both morphological classification and phylogenetic relationship.

介形类被认为是甲壳动物亚门中物种最丰富的类群之一，但在我国其分类学研究却十分薄弱，其中尤以金星介亚目的分类问题最为突出。我国已记录的160余种金星介中约2/3的报导来自古生物学和生态学领域，其中部分新记录种的描述过于简单，并缺少鉴定可依据的形态特征图，甚至有些新种的模式标本下落不明，少数种仅有裸名，因此无任何分类学意义。鉴于此，本项目基于实验室已有工作，拟通过标本交换及补点采样等方法获得尽可能覆盖我国各水域不同类型水体的标本，应用经典动物分类学方法，确定我国金星介亚目确切的科属种数及它们的地理分布，编制我国金星介亚目动物名录，绘制详尽的种的形态解剖图和地理分布图；同时，选取恰当的形态和分子等性状，应用支序系统学和分子系统学等方法，参考有效的地理分布信息及化石资料，探讨各科属间的系统发育关系。最终综合形态分类学和系统发育学研究结果，制订科学的更为自然的我国金星介亚目分类系统，编制属种检索表。

介形类被认为是甲壳动物亚门中物种最丰富的类群之一，但在我国其分类学研究却十分薄弱，其中尤以金星介亚目的分类问题最为突出。本项目基于实验室已有工作，通过标本交换及补点采样等方法获得了大量的标本。首先，本项目应用核基因18S rDNA序列、转录组和基因组、线粒体全基因序列，及形态学等证据，应用分子系统学方法，证实了金星介亚目为单系群，属于自然分类单元的事实，明确了该亚目内主要类群系统发育关系为（金星介超科+（海星介超科+大介虫超科）），并发现营底生活的金星介与营海洋浮游的壮肢介其演化速度存在较大差异。基于此，本项目应用经典动物分类学方法，通过逐一检视，结合已有文献报导，确定了我国金星介亚目确切的科属种数及它们的地理分布，编制了包含93种我国金星介亚目动物的名录，绘制了71种介形类的详尽形态解剖图。最终，本项目在综合形态分类学和系统发育学研究结果基础上，制订了科学的更为自然的我国金星介亚目分类系统，编制了属种检索表。相关成果为深入开展我国介形类分类学研究奠定了基础，弥补了国际介形类名录内缺乏中国物种记录的缺憾，并为以介形类为研究工具开展古生态和古环境研究提供了科学保障。