DiBattista Joseph D, Gaither Michelle R, Hobbs Jean-Paul A, Rocha Luiz A, Bowen Brian W
From the Department of Environment and Agriculture, Curtin University, PO Box U1987, Perth, WA 6845, Australia (DiBattista and Hobbs); Hawai'i Institute of Marine Biology, Kane'ohe, HI (Gaither and Bowen); and Section of Ichthyology, California Academy of Sciences, San Francisco, CA (Gaither and Rocha).
J Hered. 2016;107(7):647-653. doi: 10.1093/jhered/esw062. Epub 2016 Sep 20.
The pygmy angelfishes (genus Centropyge) provide numerous examples of discordance between color morphology, taxonomy, and evolutionary genetic lineages. This discordance is especially evident in the Centropyge flavissima complex, which includes three primary color morphs, three previously recognized species (C. flavissima, Centropyge eibli, and Centropyge vrolikii) and three distinct mitochondrial (mtDNA) lineages that do not align with species designations. Our previous research showed that the putative C. flavissima arose independently in the Indian and Pacific Oceans, and the three mtDNA lineages align with geography rather than species assignments. Here, we add 157 specimens to the previous dataset of 291 specimens, spread across a greater geographic range, to pinpoint the distribution of mtDNA lineages and color morphs. We found that the mtDNA lineages show remarkably strong geographic boundaries corresponding to the Indian Ocean, Central-West Pacific, and Central-South Pacific. We also test the validity of the "Black Tiger Centropyge" in the C. flavissima species complex, a taxonomic oddity that is restricted to shoals and atolls off the coast of northwestern Australia, and the newly named Centropyge cocosensis assigned to the C. flavissima lineage in the Indian Ocean. We conclude that the Black Tiger Centropyge is not a valid species but rather an intermediate between sympatric color morphs that correspond to the putative species C. eibli and C. vrolikii Our greater sampling efforts also do not support the genetic distinctiveness of C. cocosensis given shared mtDNA haplotypes with the sympatric C. eibli and C. vrolikii, but instead we find conflicting lines of evidence concerning the taxonomy of this group. We urge caution and taxonomic restraint until the true nature of this species complex can be revealed.
侏儒刺尻鱼属（Centropyge）的鱼类提供了许多颜色形态、分类学和进化遗传谱系不一致的例子。这种不一致在黄腋刺尻鱼复合体中尤为明显，该复合体包括三种主要颜色形态、三个先前认可的物种（黄腋刺尻鱼、艾氏刺尻鱼和弗氏刺尻鱼）以及三个与物种命名不相符的不同线粒体（mtDNA）谱系。我们之前的研究表明，假定的黄腋刺尻鱼在印度洋和太平洋独立出现，并且这三个mtDNA谱系与地理分布而非物种分类相对应。在这里，我们在之前291个样本的数据集基础上增加了157个样本，样本分布在更大的地理范围内，以确定mtDNA谱系和颜色形态的分布。我们发现，mtDNA谱系显示出与印度洋、中西太平洋和中南部太平洋相对应的非常明显的地理界限。我们还检验了黄腋刺尻鱼物种复合体中“黑虎刺尻鱼”的有效性，这是一种分类学上的奇特物种，仅分布于澳大利亚西北部海岸的浅滩和环礁，以及新命名的科科斯刺尻鱼，它被归入印度洋的黄腋刺尻鱼谱系。我们得出结论，黑虎刺尻鱼不是一个有效的物种，而是与假定物种艾氏刺尻鱼和弗氏刺尻鱼同域分布的颜色形态之间的中间类型。我们更大规模的采样工作也不支持科科斯刺尻鱼的遗传独特性，因为它与同域分布的艾氏刺尻鱼和弗氏刺尻鱼共享mtDNA单倍型，但相反，我们发现了关于该类群分类学的相互矛盾的证据线索。在该物种复合体的真实性质能够被揭示之前，我们敦促谨慎对待并克制进行分类学处理。
