Neopterygian phylogeny: the merger assay

The phylogenetic relationships of the recently described genus †Ticinolepis from the Middle Triassic of Monte San Giorgio are explored through cladistic analyses of the so far largest morphological data set for fossil actinopterygians, including representatives of the crown neopterygian clades Halecomorphi, Ginglymodi, and Teleostei, and merging the lists of characters from previously published systematic studies together with newly proposed characters. †Ticinolepis is retrieved as the most basal Ginglymodi and our results support the monophyly of Teleostei and Holostei, as well as Halecomorphi and Ginglymodi within the latter clade. The patterns of relationships within these clades mostly agree with previous studies, though a few important differences require future research. According to our results, ionoscopiforms are not monophyletic, caturids are not amiiforms and leptolepids and luisiellids form a monophyletic clade. Our phylogenetic hypothesis confirms the rapid radiation of the ...

本研究通过分支系统学分析，采用迄今为止规模最大的化石辐鳍鱼（actinopterygians）形态学数据集，探究了产自圣乔治山（Monte San Giorgio）中三叠统的新近记述属†提契诺鱼（Ticinolepis）的系统发育关系。该数据集涵盖新鳍鱼冠群（crown neopterygian）的弓鳍鱼型类（Halecomorphi）、梗齿鱼亚纲（Ginglymodi）与真骨鱼（Teleostei）的代表类群，并整合了此前已发表的分类学研究中的性状列表与全新提出的研究性状。系统发育分析结果显示，†提契诺鱼为最基干的梗齿鱼亚纲类群；本研究结果支持真骨鱼、全骨鱼（Holostei）的单系性，同时支持全骨鱼支系内的弓鳍鱼型类与梗齿鱼亚纲的单系性。上述支系内部的亲缘关系模式大多与此前研究结果一致，但存在若干关键差异，有待后续研究进一步厘清。此外，本研究结果表明离子鲟形目（ionoscopiforms）并非单系群，卡特鱼科（caturids）不属于弓鳍鱼目（amiiforms），而薄鳞鱼科（leptolepids）与路易西鱼科（luisiellids）构成一个单系支系。本研究提出的系统发育假说证实了……的快速辐射演化。