genus Lepus vs mammal genus

genus Lepus and mammal genus both are nouns.

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

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

genus Lepus (noun)	mammal genus (noun)
type genus of the Leporidae: hares	a genus of mammals