Dissertation Research: A Cladistic Analysis of the Deep Sea Ophiuroid Genera Ophiomusium Lyman and Ophiosphalma H.L. Clark and Their Relations Within Ophiolepididae ......

9701264 LIPSCOMB 蛇类，或脆星，是最大的一类棘皮动物。 它们几乎占据了从热带到极地海洋、从潮间带到深海的每一个海洋环境。 尽管如此，蛇类仍然是系统学研究最少的群体之一。 深海中的脆性恒星也可能为正在进行的关于深海动物起源的辩论提供信息。 一些科学家认为，深海环境是古代物种的避难所，另一些科学家则认为，深水物种是最近才出现的，是由于浅水和南极动物群的入侵。 在这项研究中，Diana Lipscomb、大卫帕森和博士候选人Susan Hottenrott将对所有海洋中深海动物群的主要成员-Ophiomusium和Ophiosphalma（蛇足虫科）-进行系统修订。 包括这些属的77个种的特征很差。 通过研究在各个博物馆存档的标本的大体和精细结构解剖，这项研究将提供这些物种的第一个详细描述和识别检索表。预计这一分析将有助于更好地了解一般的蛇类，特别是深海鱼种。 这项研究还将通过包括海洋地理学分析来深入了解深海动物群的起源，这些分析将测试这些脆性恒星起源的相互竞争的假设。

9701264 LIPSCOMB Ophiuroids, or brittle stars, are the largest class of echinoderms. They occupy nearly every marine environment from the tropics to polar seas, and the intertidal to abyssal zones. Nonetheless, ophiuroids remain one of the least studied groups with respect to their systematics. Brittle stars in the deep sea may also inform an ongoing debate about the origins of deep-sea animals. Some scientists believe that the deep-sea environment is a refuge for ancient species, others believe that deep-water species appeared more recently, by invasions from shallow-water and Antarctic faunas. In this research, Diana Lipscomb, David Pawson and doctoral candidate Susan Hottenrott will conduct a systematic revision of two ophuroid genera, Ophiomusium and Ophiosphalma (family Ophiolepididae) which are dominant members of the deep-sea fauna in all oceans. The 77 species that comprise these genera are poorly characterized. By studying the gross and fine structural anatomy of specimens archived at various museums, this study will provide the first detailed description and identification keys of these species. It is anticipated that this analysis will result in a better understanding of ophuroids in general and deep-sea species in particular. The study should also give insights into the origin of deep sea faunas, by including biogeographic analyses that will test competing hypotheses for the origins of these brittle stars.