genus Fossa vs mammal genus

genus Fossa and mammal genus both are nouns.

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

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

genus Fossa: monotypic genus of Madagascar civets closely related to palm civets
mammal genus: a genus of mammals

genus Fossa (noun)	mammal genus (noun)
monotypic genus of Madagascar civets closely related to palm civets	a genus of mammals