Aster ptarmicoides vs aster

Aster ptarmicoides and aster both are nouns.

Word	Noun	Adjective	Verb	Adverb
Aster ptarmicoides	Yes	No	No	No
aster	Yes	No	No	No

As nouns, aster is a hypernym of Aster ptarmicoides; that is, aster is a word with a broader meaning than Aster ptarmicoides:

Aster ptarmicoides: tufted rigid North American perennial with loose clusters of white flowers
aster: any of various chiefly fall-blooming herbs of the genus Aster with showy daisylike flowers

Aster ptarmicoides (noun)	aster (noun)
tufted rigid North American perennial with loose clusters of white flowers	star-shaped structure formed in the cytoplasm of a cell having fibers like rays that surround the centrosome during mitosis
	any of various chiefly fall-blooming herbs of the genus Aster with showy daisylike flowers