Diversity and Evolution of Semionotid Fishes

新罗鱼是硬骨鱼类中最重要的类群，其现代物种数量远远超过其他所有脊椎动物类群。然而，它们的早期历史仍然知之甚少，而基新古龙类之间的系统发育关系，以及硬骨鱼类的起源，仍然是个谜。其中最重要和最有争议的群体是基础neoportians的semionotid。虽然半尖齿龙是中生代沉积物中最常见的基底新尖齿龙，并且该群的成员是最早被描述的化石鱼类之一，但迄今为止，即使是它们的阿尔法分类和系统发育关系也没有得到解决。此外，semionotids在neopropterians中的系统发育位置还很不清楚。因此，目前的项目的目标是建立一个系统发育框架，以更好地了解semionodial进化和多样性，并分析其系统发育的位置neoprophians。在一个三步的方法，首先将建立最重要的属semionotids的分类，然后这些将被放在一个系统发育的背景下，最后，在前两个阶段的基础上，semionotids的位置neoprophanans将进行分析。该项目将导致更好地了解中生代neoptergian多样性和演化，以及一般的基础neoptergian的特征演化。

The Neopterygians are the most important group of bony fishes, with their Recent species numbers greatly exceeding that of all other vertebrate groups. However, their early history is still poorly understood, and the phylogenetic relationships among basal neopterygians, and thus the origin of teleosts, remain enigmatic. One of the most important and controversial groups of basal neopterygians are the semionotids. Although semionotids are among the most common basal neopterygians in Mesozoic sediments, and members of the group were among the first fossil fishes to be described, even their alpha taxonomy and their phylogenetic relationships have not been resolved so far. Furthermore, the phylogenetic position of semionotids within neopterygians is far from clear. The objectives of the current project are thus to establish a phylogenetic framework to attain a better understanding of semionotid evolution and diversity, and to analyse their phylogenetic position within neopterygians. In a three-step approach, first the taxonomy of the most important genera of semionotids will be established, then these will be put in a phylogenetic context, and finally, building on the two previous phases, the position of semionotids within neopterygians will be analysed. The project will lead to a much better understanding of Mesozoic neopterygian diversity and evolution, and character evolution in basal neopterygians in general.