genus Euthynnus vs fish genus

genus Euthynnus and fish genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
genus Euthynnus	Yes	No	No	No
fish genus	Yes	No	No	No

As nouns, fish genus is a hypernym of genus Euthynnus; that is, fish genus is a word with a broader meaning than genus Euthynnus:

genus Euthynnus (noun)	fish genus (noun)
a genus of Scombridae	any of various genus of fish