Taxonomy of myxobolid parasites of fishes

本研究对寄生于北美淡水和一些海水鱼类组织中的粘虫的分类和生活史进行了研究。这组寄生虫(目前有118个标称物种)是鱼类中寄生的最特殊的谱系之一，也是迄今了解最少的一个。有人认为，除非有一套完善的分类系统，而且非专业人士可以使用，否则我们无法理解由这些寄生虫形成的丰富群落的性质。这项研究将通过重新检查从类型寄主和其他鱼类收集的材料，对上个世纪早些时候描述的许多物种进行分类修订。它还将对其他鱼类进行广泛的搜索，寻找需要正式描述和文件的寄生虫种类。该计划的一个重要方面是让本科生和研究生接触动物命名法以及基于形态和分子(18S RDNA)的分类学。一名研究生将检验我们低估了粘球生物多样性的假设--这将通过修订来自不同鲤科寄主物种的Thelohanellus notatus来检验(是否有单一物种或单独的神秘物种独立地在不同寄主物种之间循环？)。另一名研究生将在新斯科舍省复制的沿海地点研究寄生种群Dundulus diaphanus和Fundulus Heterocltes的物种组合的分类和生活史，以及这两个物种的杂交物种。这项工作将包括设计的实地研究、实验传播以及对三个宿主组中物种状况的严格的形态和分子评估。一个长期目标是制作一份以生态为基础的北美鱼类粘球寄生虫图集。

The proposed reseach examines the taxonomy and life history of species of Myxobolus (Myxozoa) parasitic in tissues of freshwater and some marine fishes of North America. This group of parasites (currently having 118 nominal species) is one of the most speciose lineages parasitic in fishes yet one of the poorest understood. It is argued that our understanding of the nature of the rich communities formed by these parasites cannot be achieved until a sound system of taxonomy is available, and one useable by non-specialists. The research will undertake taxonomic revisions of numerous species described earlier in the last century, through reexamination of material collected from type hosts and other fishes. It will also conduct extensive searches in other fishes for species of parasites needing formal description and documentation. An important aspect of the program is the exposure of undergraduate and graduate students to zoological nomenclature and morphologically and molecularly (18S rDNA) based taxonomy. One graduate student will examine the hypothesis that we have underestimated myxobolid diversity - this will be tested through a revision of Thelohanellus notatus from different cyprinid host species (Is there a single species or separate cryptic species cycling independently through the various host species?). A second graduate student will examine the taxonomy and life history of assemblages of species of Myxobolus parasitizing populations Fundulus diaphanus and Fundulus heteroclitus in their respective freshwater and marine habitats, as well as with hybrids of the two species in replicate coastal sites in Nova Scotia. This work will involve a blend of designed field studies, experimental transmissions, and rigorous morphological and molecular assessments of species status in the three host groups. A long term goal is to produce an ecologically-based atlas of myxobolid parasites of fishes of North America