Diadophis vs reptile genus

Diadophis and reptile genus both are nouns.

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

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

Diadophis: a genus of reptiles of the family Colubridae including ringneck snakes
reptile genus: a genus of reptiles

Diadophis (noun)	reptile genus (noun)
a genus of reptiles of the family Colubridae including ringneck snakes	a genus of reptiles