drosophila vs Drosophila melanogaster

drosophila and Drosophila melanogaster both are nouns.

Word	Noun	Adjective	Verb	Adverb
drosophila	Yes	No	No	No
Drosophila melanogaster	Yes	No	No	No

As nouns, drosophila and Drosophila melanogaster are synonyms defined as:

drosophila and Drosophila melanogaster: small fruit fly used by Thomas Hunt Morgan in studying basic mechanisms of inheritance

drosophila (noun)	Drosophila melanogaster (noun)
small fruit fly used by Thomas Hunt Morgan in studying basic mechanisms of inheritance	small fruit fly used by Thomas Hunt Morgan in studying basic mechanisms of inheritance