中国洞穴步甲系统发育及地理分布格局研究

In cave ecosystem which is very particular and fragile, the species diversity is characterized by its extremely rareness, high endemism and fantasticality. As the largest and most diverse karstic areas in the world, southern China's karsts hold numerous kinds of cave resources, and bizarre cave biodiversity as well. The ground beetles, in particular, the species belonging to the tribe Trechini (Insecta: Coleoptera: Carabidae), are typical representatives of cavernicolous terrestrial animals. Almost all of the cavernicolous trechine beetles in southern China's karsts are completely blind, and some of them with extremely modified morphological characteristics. Because there is no epigeal relatives in out-cave habitats, the cave-dwelling trechine beetles must be relict species and so are regarded as “living fossils”, therewithal they are very important in terms of scientific researches and the biodiversity conservation. Based on the research achievements of other entomologists, especially of the applicant’s team, the present project is aimed at the following aspects: (1) Biological surveys in karstic areas of southern China will be carried out to understand the cavernicolous fauna of Carabidae by focusing on the tribe Trechini, its composition and structural characteristics; (2) Based on phylogenetical information conducted in the light of comparative morphology and molecular systematics, the faunal evolution and the zoogeographical pattern of the cave trechine beetles in southern China’s karsts will be analyzed. The results of above research activities will provide basic scientific evidences for further study on adaption of cavernicolous trechines and their conservation.

在洞穴这个非常特别又十分脆弱的生态系统中，洞穴生物多样性常表现为极高的稀有性、特有性和奇特性。中国是喀斯特（又称岩溶）大国，中国南方喀斯特是世界上面积最大、地貌类型最多样的喀斯特，拥有丰富的洞穴生物资源。洞穴步甲是我国陆生洞穴动物中最有代表意义的类群之一，物种资源十分丰富，外部形态高度特化，且多为复眼完全退化的盲步甲，区系组成复杂。分布于中国南方喀斯特的洞穴步甲，没有营地表生活的近亲，是冰河时期残存下来的孑遗物种，堪称活化石，具有重要的科学研究和保护价值。本项目拟在前人，特别是申请人团队近十年来已有研究工作的基础上，通过系统的调查和分类研究，基本摸清中国洞穴步甲物种多样性的构成和特点；通过系统发育分析，探讨洞穴步甲区系起源和演化关系，根据岛屿生物地理学原理，进一步解析中国洞穴步甲地理分布格局及其形成机制。研究结果将为进一步开展洞穴步甲适应机制和保护生物学研究打下科学基础。

洞穴步甲是重要的陆生洞穴动物代表类群。在中国，洞穴步甲分布广泛、物种众多、分化复杂，是研究洞穴生物演化和适应机制的理想材料。物种丰富且特化的洞穴步甲使得中国成为新的热点地区，但中国洞穴步甲的物种多样性及其系统发育关系和演化仍有待研究，因此本项目旨在继续调查中国洞穴步甲的物种多样性，并解析各类群之间的亲缘关系，探讨其系统发育和演化问题。通过系统调查，发现并报道了17新属（亚属）45新种，使得中国洞穴步甲增加至8族75属214种，其中以行步甲族最为丰富共65属180种。针对不同形态适应型的洞穴行步甲，我们应用了几何形态学对其进行分析，揭示步甲对洞穴环境的适应程度在形态学上的表现，并通过属间形态表型树，探讨不同洞穴环境适应型步甲之间的形态聚类与进化关系，发现洞穴步甲各生态类型的变异方向不同，这可能是其适应不同洞穴环境和选择压力的结果。此外，分子系统发育结果发现，中国洞穴行步甲不形成单系群，并且拥有5个独立的进化分支，结合地理分布推测不同形态适应性类型并且分布广泛的多个行步甲类群，通过不同的地理起源和地下扩殖活动，最终形成了目前这种洞穴行步甲在中国的分布格局。