Department of Earth and Environmental Sciences, University of Michigan, University Avenue, Ann Arbor, MI 48109-1079, USA.
Museum of Paleontology, University of Michigan, University Avenue, Ann Arbor, MI 48109-1079, USA.
Biol Lett. 2021 Mar;17(3):20200766. doi: 10.1098/rsbl.2020.0766. Epub 2021 Mar 10.
Actinopterygians (ray-finned fishes) are the most diverse group of living fishes, but have a sparse Devonian fossil record restricted to low palaeolatitudes. Here we report a new actinopterygian from the Paraná Basin of Brazil, which occupied a circumpolar position in the Palaeozoic. Available geological evidence supports a Middle Devonian or older age for this taxon, which shares features of the mandibular symphysis with the latest Devonian . A phylogenetic analysis resolves these two as sister taxa. This new record expands the palaeogeographic distribution of Devonian ray-fins and suggests that gaps in their fossil record might be filled by exploring poorly sampled high-latitude localities within the Malvinokaffric Realm.
肉鳍鱼类（条鳍鱼类）是现存鱼类中最多样化的群体，但泥盆纪的化石记录却很少，仅限于低纬度地区。在这里，我们报告了一种来自巴西巴拉那盆地的新肉鳍鱼类，它在古生代占据了极地位置。现有的地质证据支持这个分类单元的中泥盆世或更老的年龄，它与最晚泥盆世的下颌骨联合具有共同的特征。系统发育分析将这两个分类单元确定为姐妹分类单元。这一新记录扩大了泥盆纪射线鳍鱼类的古地理分布范围，并表明通过探索马尔维纳斯科夫区（Malvinokaffric Realm）内采样不足的高纬度地区，可能填补它们化石记录中的空白。
