ring-necked pheasant vs Phasianus colchicus

ring-necked pheasant and Phasianus colchicus both are nouns.

Word	Noun	Adjective	Verb	Adverb
ring-necked pheasant	Yes	No	No	No
Phasianus colchicus	Yes	No	No	No

As nouns, ring-necked pheasant and Phasianus colchicus are synonyms defined as:

ring-necked pheasant and Phasianus colchicus: common pheasant having bright plumage and a white neck ring

ring-necked pheasant (noun)	Phasianus colchicus (noun)
common pheasant having bright plumage and a white neck ring	common pheasant having bright plumage and a white neck ring