Zamia pumila vs zamia

Zamia pumila and zamia both are nouns.

Word	Noun	Adjective	Verb	Adverb
Zamia pumila	Yes	No	No	No
zamia	Yes	No	No	No

As nouns, zamia is a hypernym of Zamia pumila; that is, zamia is a word with a broader meaning than Zamia pumila:

Zamia pumila: small tough woody zamia of Florida and West Indies and Cuba; roots and half-buried stems yield an arrowroot
zamia: any of various cycads of the genus Zamia; among the smallest and most verdant cycads

Zamia pumila (noun)	zamia (noun)
small tough woody zamia of Florida and West Indies and Cuba; roots and half-buried stems yield an arrowroot	any of various cycads of the genus Zamia; among the smallest and most verdant cycads