Kontula Tytti, Väinölä Risto
Department of Ecology and Systematics, PO Box 65, FIN-00014 University of Helsinki, Finland.
Mol Ecol. 2003 Nov;12(11):3179-84. doi: 10.1046/j.1365-294x.2003.01963.x.
The relationships among Myoxocephalus quadricornis complex fish from Arctic coastal waters and from 'glacial relict' populations in Nearctic and Palearctic postglacial lakes were assessed using mtDNA sequence data (1978 bp). A principal phylogeographical split separated the North American continental deepwater sculpin (M. q. thompsonii) from a lineage of the Arctic marine and North European landlocked populations of the fourhorn sculpin (M. q. quadricornis). The North American continental invasion took place several glaciation cycles ago in the Early-to-Middle Pleistocene (0.9% sequence divergence); the divergence of the European and Arctic populations was somewhat later (0.5% divergence). The Nearctic-Palearctic freshwater vicariance in Myoxocephalus, however, appears clearly younger than in similarly distributed 'glacial relict' crustacean taxa; the phylogeographical structure is more similar to that in other northern Holarctic freshwater fish complexes.
利用线粒体DNA序列数据（1978碱基对）评估了北极沿海水域的四角杜父鱼复合体鱼类与近北极和古北界冰后期湖泊中“冰川残遗”种群之间的关系。一个主要的系统地理学分歧将北美大陆深水杜父鱼（M. q. thompsonii）与北极海洋和北欧内陆四角杜父鱼（M. q. quadricornis）的一个谱系区分开来。北美大陆的入侵发生在早更新世至中更新世的几个冰川周期之前（序列分歧为0.9%）；欧洲和北极种群的分歧稍晚一些（分歧为0.5%）。然而，杜父鱼属的近北极-古北界淡水替代现象明显比分布类似的“冰川残遗”甲壳类分类群更为年轻；其系统地理结构与其他北极淡水鱼复合体更为相似。
