线粒体DNA序列变异显示鸭绿江茴鱼为黑龙江茴鱼同物异名

经测序获得北极茴鱼鸭绿江亚种Thymallus arcticus yaluensis和黑龙江茴鱼T.grubii共26尾的线粒体DNA控制区基因全序列,以下游黑龙江茴鱼T.tugarinae、北极茴鱼指名亚种T.a.arcticus和欧洲茴鱼T.thymallus作外群,构建了茴鱼属部分种分子系统发育树,以探讨北极茴鱼鸭绿江亚种分类地位的有效性。结果显示,鸭绿江茴鱼与黑龙江茴鱼的4个地理种群(呼玛河、甘河、牡丹江、松花江)间的Kimura 2-parameter遗传距离仅为0·007~0·015,处于黑龙江茴鱼不同地理种群间的变异范围之内(0·004~0·015),明显小于属内种间的遗传距离(0·046~0·062)。以邻接法(NJ)和最大简约法(MP)构建的茴鱼属部分种系统发育树表明,鸭绿江茴鱼未构成独立的单系群,也未与北极茴鱼T.a.arcticus形成亚种关系,而是聚到黑龙江茴鱼种群内部,共同构为一个单系群。研究表明,鸭绿江茴鱼T.a.yaluensis并非有效种,应为黑龙江茴鱼T.grubii的同物异名,可视为黑龙江茴鱼的一个地理生态种群。

THYMALLUS ARCTICUS YALUENSIS IS A SYNONYM OF T GRUBII BY MITOCHONDRIAL CONTROL REGION SEQUENCES ANALYSIS

26 complete mitochondrial control region sequences of Thymallus arcticus yaluensis and T. grubii were sequenced, to investigate the validity of T. a. yaluensis, and constructed the phylogenetic relationships of Thymallus (T.) tugarinae, T. a. arcticus and T. thymallus were used as outgroups. The results showed the average K 2-P genetic distances between T. a. yaluensis and the four populations of T. grubii (Huma reiver, Gan River, Mudan River and Songhua River population) ranged from 0.007 to 0.015, and the average genetic distances among the four populations of T. grubii ranged from 0.004 to 0.015, thus both showing significant lower between different Thymallus (0.046-0.062).The phylogenetic trees estimated by neighbor-joining (NJ) and maximum parsimony (MP) methods indicated that the individuals of T. a. yaluensis failed to form monophyletic clades, and not a subsepecies of T. a. arcticus, but formed monophyletic clades with T. grubii. These results revealed that T. a. yaluensis should not be considered a valid species, but is a synonym of T. grubii, and just a population of T. grubii.