Souza Camila S, Melo Bruno F, Mattox George M T, Oliveira Claudio
Departamento de Biologia Estrutural e Funcional, Instituto de Biociências, Universidade Estadual Paulista, R. Prof. Dr. Antônio C. W. Zanin 250, 18618-689 Botucatu, SP, Brazil.
Department of Ichthyology, Division of Vertebrate Zoology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA.
Mol Phylogenet Evol. 2022 Jun;171:107462. doi: 10.1016/j.ympev.2022.107462. Epub 2022 Mar 28.
Characinae is one of the most species-rich subfamilies of Characidae and holds special taxonomic importance because it includes Charax, type-genus of Characidae and Characiformes. Currently, the monophyly and the hypotheses of intergeneric and interspecific relationships of Characinae are based on a few morphological and molecular studies but all with low species coverage. Given their diversity, taxonomic importance, and the lack of a taxon-dense phylogeny, we sought to buttress the systematic understanding of Characinae collecting DNA sequence data from ultraconserved elements (UCEs) of the genome from 98 specimens covering 57 species (61%) plus 17 characiforms as outgroups. We used maximum likelihood, Bayesian inference, and coalescent-based species tree approaches and the resulting phylogeny with 1,300 UCE loci (586,785 characters) reinforced the monophyly of the subfamily as well as of six genera: Acestrocephalus, Charax, Cynopotamus, Galeocharax, Phenacogaster, and Roeboides. The phylogeny provides a hypothesis of intergeneric and interspecific relationships for the subfamily with Phenacogaster sister to all genera, and Acanthocharax sister to Cynopotamini (Cynopotamus (Acestrocephalus Galeocharax)) and Characini (Charax Roeboides). We propose a new tribe Acanthocharacini to allocate Acanthocharax, two subclades for Phenacogaster, two for Cynopotamus, three for Charax, and reinforced the four subclades for Roeboides previously identified by morphological studies. Additionally, we generated a time-calibrated phylogeny for Characinae that suggested an initial diversification during the Miocene at around 19 million years ago and discussed historical biogeographic events for major subclades. The results obtained here will contribute to the development of further research on the evolutionary processes modulating species diversification in Characinae.
脂鲤亚科是脂鲤科中物种最为丰富的亚科之一，具有特殊的分类学重要性，因为它包含脂鲤科和脂鲤目的模式属脂鲤属。目前，脂鲤亚科的单系性以及属间和种间关系的假说基于一些形态学和分子研究，但所有这些研究的物种覆盖范围都很低。鉴于它们的多样性、分类学重要性以及缺乏一个分类密集的系统发育树，我们试图通过从98个标本的基因组超保守元件（UCEs）中收集DNA序列数据来加强对脂鲤亚科的系统理解，这些标本涵盖57个物种（61%），另外还有17个脂鲤目物种作为外类群。我们使用了最大似然法、贝叶斯推断和基于溯祖的物种树方法，由此得到的包含1300个UCE位点（586,785个字符）的系统发育树强化了该亚科以及六个属的单系性，这六个属分别是：尖头脂鲤属、脂鲤属、犬形脂鲤属、似真小脂鲤属、真唇脂鲤属和似魮脂鲤属。该系统发育树为该亚科提供了一个属间和种间关系的假说，其中真唇脂鲤属是所有属的姐妹群；棘脂鲤属是犬形脂鲤族（犬形脂鲤属（尖头脂鲤属 似真小脂鲤属））和脂鲤族（脂鲤属 似魮脂鲤属）的姐妹群。我们提出了一个新族棘脂鲤族来安置棘脂鲤属，为真唇脂鲤属划分了两个亚分支，为犬形脂鲤属划分了两个亚分支，为脂鲤属划分了三个亚分支，并强化了之前通过形态学研究确定的似魮脂鲤属的四个亚分支。此外，我们还生成了一个脂鲤亚科的时间校准系统发育树，表明其在大约1900万年前的中新世开始初步分化，并讨论了主要亚分支的历史生物地理事件。这里获得的结果将有助于推动对调节脂鲤亚科物种多样化的进化过程的进一步研究。
