REVSYS: Revisionary Systematics of Hawaiian Mecyclothorax Beetles (Coleoptera: Carabidae)

康奈尔大学的James Liebherr博士获得了一笔拨款，用于对夏威夷甲壳甲虫属的甲壳甲虫进行分类修订。这一类群表现出极其迅速的物种形成；目前的估计表明，近200个物种是从不到200万年前在毛伊岛或莫洛凯岛定居的同一个祖先进化而来的，这一物种形成速度比相关的大陆物种快16-40倍。这些物种中有一半以上是未被描述的，其中许多是PI及其同事在过去12年的野外工作中新收集的。对五个以前未研究过的湿森林地区进行两次实地考察，将改善该群体物种采样的地理覆盖范围。形态学特征将被研究，以产生一个物种的系统发育假说。这项分析将包括来自西南太平洋的许多胸甲物种，从而发现夏威夷辐射的来源。这一假设将作为研究驱动快速物种形成的进化力量的框架。这些字符还将构成识别关键字的基础——无论是基于网络的还是印刷出版的——这将使科学家和资源管理者能够识别单个标本。因为胸甲动物具有生境特异性。在面对不断增加的外来物种引进时，准确的识别将提高监测这些生态状况的能力。该项目将比较Mecyclothorax的系统发育模式与独立的夏威夷carabid甲虫辐射（blackburnia的131种）的系统发育模式，以测试进化生物地理学范式的有效性。夏威夷群岛的已知年龄为该测试提供了强大的时间限制，使夏威夷系统成为进行该调查的理想场所。系统发育假说也将允许阐明在这种辐射的进化过程中生态偏好是如何改变的。

A grant has been awarded to Dr. James Liebherr at Cornell University to taxonomically revise Hawaiian carabid beetle species in the genus Mecyclothorax. This group demonstrates extremely rapid speciation; current estimates suggest that the nearly 200 species have evolved from a single ancestor that colonized either Maui or Molokai less than 2 million years ago, a speciation rate 16-40 times more rapid that related mainland species. More than half of these species are undescribed, many having been newly collected by the PI and colleagues during field work over the past 12 years. Two field expeditions to five previously unstudied wet-forest areas will improve geographic coverage for species sampling of the group. Morphological characters will be studied in order to produce a phylogenetic hypothesis of the species. The analysis will include numerous Mecyclothorax species from across the southwest Pacific Ocean, allowing the source for the Hawaiian radiation to be discovered. This hypothesis will serve as the framework within which evolutionary forces driving rapid speciation will be studied. These characters will also form the basis for identification keys-both web-based and print-published-that will enable scientists and resource managers to identify individual specimens.Because Mecyclothorax species exhibit habitat specificity-e.g., restriction to particular plant species, microhabitats, or life zones-accurate identification will enhance the ability to monitor such ecological situations in the face of ever-increasing alien species introductions. The PI will compare phylogenetic patterns in Mecyclothorax with those in an independent Hawaiian carabid beetle radiation-the 131-species of Blackburnia-to test the validity of the cladistic biogeographic paradigm. Known ages of the Hawaiian Islands provide powerful chronological constraints in this test, making the Hawaiian system an ideal venue for carrying out this investigation. The phylogenetic hypothesis will also permit elucidation of how ecological preferences have changed during evolution of this radiation.