七鳃鳗，八目鳗一种七鳃鳗科的原始细长淡水或溯河产卵鱼，特点是长有无。

Any of various primitive elongated freshwater or anadromous fishes of the family Petromyzontidae, characteristically having a jawless sucking mouth with rasping teeth.

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彩虹鳟中的溯河产卵海鱼，较淡水种类体型大，斑点颜色淡。

The anadromous variety of rainbow trout, being larger and having darker spots than the freshwater variety.

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