Origin and evolution of freshwater amphidromy: Suggestion of a new migration type

在对Sicyopterus Sicydiinae亚科中唯一的温带种Sicyopterus Sicydiinae的生态学研究中，我们发现黑潮流对幼虫的扩散具有重要的依赖性，并且缺乏内陆或河流形式。其幼虫在海洋中的分散和生活史特征在河流中发挥了作用，在该物种的温带分布。所有物种在热带地区的Sicydiine幼虫阶段可能需要在海洋中发生，但在温带地区的香鱼，杜父鱼和galaxiids具有内陆或河流形式，其幼虫不需要进入海洋进行幼虫喂养和生长。这表明，Sicydiine幼虫具有较高的海洋依赖性，而香鱼，杜父鱼和galaxiid幼虫具有较低的海洋依赖性。热带和温带淡水两栖类鱼类在其生活史的进化过程中似乎发展了两种不同的策略。

During ecological research of Sicyopterus japonicus, which is the only temperate species of the subfamily Sicydiinae, we found larval dispersion by Kuroshio Current, an essential larval dependence on growth in the ocean, and a lack of landlocked or fluvial forms. Their larval dispersion in the ocean and life history characteristics in the river has played a role in the temperate distribution of this species. The Sicydiine larval stage in tropical areas may be required to occur in the ocean for all species, but ayu, sculpins and galaxiids in temperate areas have landlocked or fluvial forms with larvae that do not need to enter the ocean for larval feeding and growth. This suggests that Sicydiine larvae have a high oceanic dependency, whereas ayu, sculpins and galaxiid larvae have a low oceanic dependency. Freshwater amphidromous fish in tropical and temperate areas appear to have developed two different strategies in the evolution of their life histories.