apple aphid vs aphid

apple aphid and aphid both are nouns.

Word	Noun	Adjective	Verb	Adverb
apple aphid	Yes	No	No	No
aphid	Yes	No	No	No

As nouns, aphid is a hypernym of apple aphid; that is, aphid is a word with a broader meaning than apple aphid:

apple aphid: bright green aphid; feeds on and causes curling of apple leaves
aphid: any of various small plant-sucking insects

apple aphid (noun)	aphid (noun)
bright green aphid; feeds on and causes curling of apple leaves	any of various small plant-sucking insects