Primula vulgaris vs primula

Primula vulgaris and primula both are nouns.

Word	Noun	Adjective	Verb	Adverb
Primula vulgaris	Yes	No	No	No
primula	Yes	No	No	No

As nouns, primula is a hypernym of Primula vulgaris; that is, primula is a word with a broader meaning than Primula vulgaris:

Primula vulgaris: plant of western and southern Europe widely cultivated for its pale yellow flowers
primula: any of numerous short-stemmed plants of the genus Primula having tufted basal leaves and showy flowers clustered in umbels or heads

Other hypernyms of Primula vulgaris include primrose.

Primula vulgaris (noun)	primula (noun)
plant of western and southern Europe widely cultivated for its pale yellow flowers	any of numerous short-stemmed plants of the genus Primula having tufted basal leaves and showy flowers clustered in umbels or heads