Petromyzon marinus vs lamprey

Petromyzon marinus and lamprey both are nouns.

Word	Noun	Adjective	Verb	Adverb
Petromyzon marinus	Yes	No	No	No
lamprey	Yes	No	No	No

As nouns, lamprey is a hypernym of Petromyzon marinus; that is, lamprey is a word with a broader meaning than Petromyzon marinus:

Petromyzon marinus: large anadromous lamprey sometimes used as food; destructive of native fish fauna in the Great Lakes
lamprey: primitive eellike freshwater or anadromous cyclostome having round sucking mouth with a rasping tongue

Other hypernyms of Petromyzon marinus include lamper eel, lamprey eel.

Petromyzon marinus (noun)	lamprey (noun)
large anadromous lamprey sometimes used as food; destructive of native fish fauna in the Great Lakes	primitive eellike freshwater or anadromous cyclostome having round sucking mouth with a rasping tongue