subphylum Craniata vs fish genus

subphylum Craniata and fish genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
subphylum Craniata	Yes	No	No	No
fish genus	Yes	No	No	No

subphylum Craniata (noun)	fish genus (noun)
fishes, amphibians, reptiles, birds, mammals	any of various genus of fish