鳗类，鳗：无颚的各种原始水生圆口纲脊椎动物中的一种，包括七鳃鳗和盲鳗。

Any of various primitive aquatic vertebrates of the class Cyclostomata, lacking jaws and including the lampreys and hagfishes.

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鳗类，鳗：无颚的各种原始水生圆口纲脊椎动物中的一种，包括七鳃鳗和盲鳗。

Any of various primitive aquatic vertebrates of the class Cyclostomata, lacking jaws and including the lampreys and hagfishes.

youdao