Natrix vs reptile genus

Natrix and reptile genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
Natrix	Yes	No	No	No
reptile genus	Yes	No	No	No

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

Natrix (noun)	reptile genus (noun)
water snakes; a cosmopolitan genus	a genus of reptiles