Liomys vs mammal genus

Liomys and mammal genus both are nouns.

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

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

Liomys: pocket mice, containing the Panamanian spiny pocket mouse, Mexican spiny pocket mouse, painted spiny pocket mouse, Salvin's spiny pocket mouse, and Jaliscan spiny pocket mouse (Liomys)
mammal genus: a genus of mammals

Liomys (noun)	mammal genus (noun)
pocket mice, containing the Panamanian spiny pocket mouse, Mexican spiny pocket mouse, painted spiny pocket mouse, Salvin's spiny pocket mouse, and Jaliscan spiny pocket mouse (Liomys)	a genus of mammals