genus Thomomys vs mammal genus

genus Thomomys and mammal genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
genus Thomomys	Yes	No	No	No
mammal genus	Yes	No	No	No

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

genus Thomomys (noun)	mammal genus (noun)
western pocket gophers	a genus of mammals