PDF(Pubmed)
Abstract：
For almost 200 years, the taxonomy of cutthroat trout (Oncorhynchus clarkii), a salmonid native to Western North America, has been in flux as ichthyologists and fisheries biologists have tried to describe the diversity within these fishes. Starting in the 1950s, Robert Behnke reexamined the cutthroat trout and identified 14 subspecies based on morphological traits, Pleistocene events, and modern geographic ranges. His designations became instrumental in recognizing and preserving the remaining diversity of cutthroat trout. Over time, molecular techniques (i.e. karyotypes, allozymes, mitochondrial DNA, SNPs, and microsatellite arrays) have largely reinforced Behnke\'s phylogenies, but have also revealed that some relationships are consistently weakly supported. To further resolve these relationships, we generated de novo transcriptomes for nine cutthroat subspecies, as well as a Bear River Bonneville form and two Colorado River lineages (blue and green). We present phylogenies of these subspecies generated from multiple sets of orthologous genes extracted from our transcriptomes. We confirm many of the relationships identified in previous morphological and molecular studies, as well as discuss the importance of significant differences apparent in our phylogenies from these studies within a geological perspective. Specific findings include three distinct clades: (1) Bear River Bonneville form and Yellowstone cutthroat trout; (2) Bonneville cutthroat trout (n = 2); and (3) Greenback and Rio Grande cutthroat trout. We also identify potential gene transfer between Bonneville cutthroat trout and a population of Colorado River green lineage cutthroat trout. Using these findings, it appears that additional groups warrant species-level consideration if other recent species elevations are retained.
摘要：
近200年来,刺喉鳟鱼(Oncorhynchusclarkii)的分类学，一种原产于北美西部的鲑鱼，由于鱼类学家和渔业生物学家试图描述这些鱼类的多样性，因此一直在变化。从1950年代开始,RobertBehnke重新审视了这只残酷的鳟鱼，并根据形态特征确定了14个亚种，更新世事件,和现代地理范围。他的任命有助于识别和保护残酷鳟鱼的剩余多样性。随着时间的推移,分子技术(即核型，同工酶，线粒体DNA,SNPs,和微卫星阵列)在很大程度上加强了Behnke的系统发育，但也揭示了一些关系一直受到弱支持。为了进一步解决这些关系，我们为九个残酷的亚种产生了从头转录组，以及熊河Bonneville形式和两个Colorado河血统（蓝色和绿色）。我们介绍了从转录组提取的多组直系同源基因产生的这些亚种的系统发育。我们确认了以前的形态学和分子研究中确定的许多关系，以及从地质角度讨论我们的系统发育明显差异的重要性。具体发现包括三个不同的进化枝：（1）熊河邦纳维尔形态和黄石残酷鳟鱼；（2）邦纳维尔残酷鳟鱼（n=2）；（3）格林贝克和里奥格兰德残酷鳟鱼。我们还确定了Bonneville残酷鳟鱼与Colorado河绿色血统残酷鳟鱼之间的潜在基因转移。利用这些发现，如果保留其他最近的物种海拔，则似乎需要额外的群体考虑物种水平。
