触形大疣蛛区域性演化模式的探讨

A Study on the Regional Evolution Model of Macrothele palpator

触形大疣蛛是中国中东部唯数不多的广布性的地穴型原蛛。对触形大疣蛛地理区系演化进行研究,旨在探明其时空演化规律,核实或细化学界的某些观点。作者在前期研究基础上,通过采用形态特征比值的定量聚类分析方法获得了该蛛26个样点间演化关系的支序图,分析表明:触形大疣蛛种系源自于泥盆纪前东南盆地西北侧西南至东北向短暂相融形成的弧形海湾的多个侵入点,同时,伴随地质构造运动出现的种间分化是发生于这段时期的主要事件;结合近期在缅甸琥珀中发现1亿年前的有尾蜘蛛,推测该蛛来源于西南方向的可能性更大些;随着浙闽地区的抬升使保留于“湘赣岛海”的种系逐渐由西向东渗入,因第三纪地质气候变迁归于平缓,便出现了江西境内的适应性辐射演化;第四纪冰期后,泛江西区域的触形大疣蛛种系进入到深度分化和种群细分阶段。由于线粒体标记被广泛用于种内遗传结构和种群历史等各类研宄中。为进一步核实和细化该地理演化路径或明确其与地质地层发育的关系,作者拟采用线粒体标记等对更多样点的触形大疣蛛样本的遗传分化状态进行综合分析,期待更真实的种群细分,以破解其演化历程。在综述其相关的研究背景后,作者认为该蛛作为该区域地球地质等中长期环境变化的指示生物或许是最佳选择。

Macrothele palpator is a crypt original spider of the only widely distributed in the central and eastern of China. The geographical evolution of M. palpator is studied to ascertain a law of this spider speciation within temporal and spatial evolution of the region, to verify or to refine a view put forward by some scholars. On the basis of previous studies, the authors obtain the cladistic chart of 26 points between these taxa by using the quantitative cluster analysis with the ratio of morphological characteristic value of M. palpator, and the results show that the species of M. palpator originated from several intrusive points of the arc-shaped bay formed from the southwest to the northeast of the south-west side of the pre-Devonian basin. And at the same time, the interspecific differentiation accompanied by geological tectonic movement is the main event in this period. Combined with the recent discovery of a 100 million years ago tail spider in Myanmar Amber, it is more likely that the spider originated in the southwest. With the uplift of Zhejiang and Fujian regions, the species retained in the "Xianggan Island Sea" gradually infiltrated from west to east, and the adaptive radiation evolution occurred in Jiangxi because the Tertiary geological and climatic changes were gentle. After the Quaternary glacial period, the species of M. palpator in Pan-Jiangxi region entered the stage of deep differentiation and population subdivision. The mitochondrial marker is widely used in the research of intraspecific genetic structure and population history and so on. So, to further verify and refine the geographic evolution way or clarify its relationship with the geological formation and development of its distribution areas, the applicant intends to analyze the state of genetic differentiation of spider samples from more diverse points in molecular level by using the mitochondrial marker and so on, looking for a more reliable population subdivision to unveil its evolution. In a word, it is concluded that M. palpator as an organism indicator of medium and long-term environmental changes in the earth's geology, may be the best choice after the review of its related research background.