Phylogenetic Relationships of Five Asian Schilbid Genera Including Clupisoma (Siluriformes: Schilbeidae)

The phylogenetic relationships of Asian schilbid catfishes of the genera Clupisoma, Ailia, Horabagrus, Laides and Pseudeutropius are poorly understood, especially those of Clupisoma. Herein, we reconstruct the phylogeny of 38 species of catfishes belonging to 28 genera and 14 families using the concatenated mitochondrial genes COI, cytb, and 16S rRNA, as well as the nuclear genes RAG1 and RAG2. The resulting phylogenetic trees consistently place Clupisoma as the sister taxon of Laides, and the five representative Asian schilbid genera form two monophyletic groups with the relationships (Ailia (Laides, Clupisoma)) and (Horabagrus, Pseudeutropius). The so-called “Big Asia” lineage relates distantly to African schilbids. Independent analyses of the mitochondrial and nuclear DNA data yield differing trees for the two Asian schilbid groups. Analyses of the mitochondrial gene data support a sister-group relationship for (Ailia (Laides, Clupisoma)) and the Sisoroidea and a sister-taxon association of (Horabagrus, Pseudeutropius) and the Bagridae. In contrast, analyses of the combined nuclear data indicate (Ailia (Laides, Clupisoma)) to be the sister group to (Horabagrus, Pseudeutropius). Our results indicate that the Horabagridae, recognized by some authors as consisting of Horabagrus, Pseudeutropius and Clupisoma does not include the latter genus. We formally erect a new family, Ailiidae fam. nov. for a monophyletic Asian group comprised of the genera Ailia, Laides and Clupisoma.

目前学界对Clupisoma、Ailia、Horabagrus、Laides及Pseudeutropius这5个属的亚洲锡伯鲶类（schilbid catfishes）的系统发育关系认知尚浅，其中尤以Clupisoma属的相关研究最为匮乏。本研究通过联合拼接线粒体基因细胞色素氧化酶亚基I（COI）、细胞色素b（cytb）、16S核糖体RNA（16S rRNA）以及核基因RAG1和RAG2，对隶属于14科28属的38种鲶鱼开展系统发育重建。所得系统发育树均一致显示，Clupisoma与Laides构成姊妹群；5个代表性亚洲锡伯鲶属可划分为两个单系群，其系统发育关系为((Ailia, Laides), Clupisoma)与(Horabagrus, Pseudeutropius)。所谓的‘大亚洲’支系与非洲锡伯鲶科类群亲缘关系较远。对线粒体DNA与核DNA数据分别进行独立分析，结果显示两个亚洲锡伯鲶类群的系统发育树存在差异。线粒体基因数据分析结果支持((Ailia, Laides), Clupisoma)与锡伯超科（Sisoroidea）构成姊妹群，且(Horabagrus, Pseudeutropius)与鲿科（Bagridae）互为姊妹群。与之相反，联合核基因数据分析则表明((Ailia, Laides), Clupisoma)与(Horabagrus, Pseudeutropius)互为姊妹群。本研究结果显示，部分学者提出的霍氏鲶科（Horabagridae）曾被认为包含Horabagrus、Pseudeutropius与Clupisoma三个属，但该类群并不包含Clupisoma属。本研究正式建立新科艾氏鲶科（Ailiidae fam. nov.），以涵盖由Ailia、Laides及Clupisoma三个属组成的单系亚洲类群。