Erica vagans vs erica

Erica vagans and erica both are nouns.

Word	Noun	Adjective	Verb	Adverb
Erica vagans	Yes	No	No	No
erica	Yes	No	No	No

As nouns, erica is a hypernym of Erica vagans; that is, erica is a word with a broader meaning than Erica vagans:

Erica vagans: bushy shrub having pink to white flowers; common on the moors of Cornwall and in southwestern Europe; cultivated elsewhere
erica: any plant of the genus Erica

Other hypernyms of Erica vagans include true heath.

Erica vagans (noun)	erica (noun)
bushy shrub having pink to white flowers; common on the moors of Cornwall and in southwestern Europe; cultivated elsewhere	any plant of the genus Erica