Maxostoma vs fish genus

Maxostoma and fish genus both are nouns.

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

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

Maxostoma (noun)	fish genus (noun)
a genus of fish in the family Catostomidae	any of various genus of fish