Gadus merlangus vs Merlangus merlangus

Gadus merlangus and Merlangus merlangus both are nouns.

Word	Noun	Adjective	Verb	Adverb
Gadus merlangus	Yes	No	No	No
Merlangus merlangus	Yes	No	No	No

As nouns, Gadus merlangus and Merlangus merlangus are synonyms defined as:

Gadus merlangus and Merlangus merlangus: a food fish of the Atlantic waters of Europe resembling the cod; sometimes placed in genus Gadus

Other synonyms of Gadus merlangus include whiting.

Gadus merlangus (noun)	Merlangus merlangus (noun)
a food fish of the Atlantic waters of Europe resembling the cod; sometimes placed in genus Gadus	a food fish of the Atlantic waters of Europe resembling the cod; sometimes placed in genus Gadus