渓魚

1. Origins, structure, and basic meaning

• Structure: Written 渓魚 and read けいぎょ, it collectively denotes fish that inhabit clear mountain streams and small upland rivers.
• Basic usage: It is used for observing such fish in a stream and for introducing mountain-river species in a guide.

2. Common pitfalls and similar expressions

• A habitat group, not one species name
  • The term groups fish by their stream habitat rather than identifying a single species.