Myrcia vs magnoliopsid genus

Myrcia and magnoliopsid genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
Myrcia	Yes	No	No	No
magnoliopsid genus	Yes	No	No	No

As nouns, magnoliopsid genus is a hypernym of Myrcia; that is, magnoliopsid genus is a word with a broader meaning than Myrcia:

Myrcia: a genus of tropical American trees and shrubs of the myrtle family
magnoliopsid genus: genus of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination

Other hypernyms of Myrcia include dicot genus.

Myrcia (noun)	magnoliopsid genus (noun)
a genus of tropical American trees and shrubs of the myrtle family	genus of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination