Molecular phylogeny and revised classification of the haplotilapiine cichlid fishes formerly referred to as “Tilapia”

African cichlids formerly referred to as ”Tilapia” represent a paraphyletic species assemblage belonging to the so called haplotilapiine lineage which gave rise to the spectacular East African cichlid radiations (EARs) as well as to globally important aquaculture species. We present a comprehensive molecular phylogeny of representative haplotilapiine cichlids, combining in one data set four mitochondrial and five nuclear loci for 76 species, and compare it with phylogenetic information of a second data set of 378 mitochondrial ND2 haplotypes representing almost all important “Tilapia” or Tilapia-related lineages as well as most EAR lineages. The monophyly of haplotilapiines is supported, as is the nested sister group relationship of Etia and mouthbrooding tilapiines with the remaining haplotilapiines. The latter are consistently placed in eight monophyletic clades over all datasets and analyses, but several dichotomous phylogenetic relationships appear compromised by cytonuclear discordant phylogenetic signal. Based on these results as well as on extensive morphological evidence we propose a novel generic and suprageneric classification including a (re-)diagnosis of 20 haplotilapiine cichlid genera and nine tribes. New tribes are provided for the former subgenera Coptodon Gervais, 1853, HeterotilapiaRegan, 1920 and PelmatolapiaThys van den Audenaerde, 1969, in addition for “Tilapia” joka, Tilapia sensu stricto and Chilochromis, Etia, Steatocranus sensu stricto, the mouthbrooding tilapiines and for a clade of West African tilapiines.

曾被称为“罗非鱼（Tilapia）”的非洲慈鲷，属于一类并系物种集合，隶属于所谓的带形罗非鱼支系（haplotilapiine lineage）——该支系既催生了极具标志性的东非慈鲷适应性辐射（East African cichlid radiations, EARs），也演化出全球范围内具有重要经济价值的水产养殖物种。本研究针对代表性带形罗非鱼慈鲷开展综合分子系统发育分析，将76个物种的4个线粒体基因座与5个核基因座整合至单一数据集，并将该分析结果与第二套数据集的系统发育信息进行对比；第二套数据集包含378个线粒体ND2单倍型（mitochondrial ND2 haplotypes），几乎涵盖了所有重要的“罗非鱼（Tilapia）”或罗非鱼相关类群支系，以及多数东非慈鲷适应性辐射（EARs）类群支系。带形罗非鱼类群的单系性得到支持，埃蒂亚属（Etia）与口育型罗非鱼类群构成的嵌套姐妹群与其余带形罗非鱼类群的亲缘关系同样得到验证。上述其余带形罗非鱼类群在所有数据集与分析中均被稳定划分为8个单系演化支，但部分二分系统发育关系因核质冲突的系统发育信号而无法得到明确解析。基于上述研究结果及大量形态学证据，本研究提出一套全新的属级与超属级分类系统，其中包含20个带形罗非鱼慈鲷属及9个族的（重新）鉴别特征。本研究为原亚属库珀非鱼属（Coptodon Gervais, 1853）、异罗非鱼属（Heterotilapia Regan, 1920）和佩尔马罗非鱼属（Pelmatolapia Thys van den Audenaerde, 1969）设立新族，此外还为"Tilapia" joka、狭义罗非鱼属（Tilapia sensu stricto）、奇罗非鱼属（Chilochromis）、埃蒂亚属（Etia）、狭义裸头慈鲷属（Steatocranus sensu stricto）、口育型罗非鱼类群，以及由西非罗非鱼类群构成的演化支设立新族。