genus Roccus vs fish genus

genus Roccus and fish genus both are nouns.

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

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

genus Roccus: a genus of Serranidae, including the common marine striped bass (Roccus)
fish genus: any of various genus of fish

genus Roccus (noun)	fish genus (noun)
a genus of Serranidae, including the common marine striped bass (Roccus)	any of various genus of fish