gall midge vs dipterous insect

gall midge and dipterous insect both are nouns.

Word	Noun	Adjective	Verb	Adverb
gall midge	Yes	No	No	No
dipterous insect	Yes	No	No	No

As nouns, dipterous insect is a hypernym of gall midge; that is, dipterous insect is a word with a broader meaning than gall midge:

gall midge: fragile mosquito-like flies that produce galls on plants
dipterous insect: insects having usually a single pair of functional wings (anterior pair) with the posterior pair reduced to small knobbed structures and mouth parts adapted for sucking or lapping or piercing

Other hypernyms of gall midge include dipteran, dipteron, two-winged insects.

gall midge (noun)	dipterous insect (noun)
fragile mosquito-like flies that produce galls on plants	insects having usually a single pair of functional wings (anterior pair) with the posterior pair reduced to small knobbed structures and mouth parts adapted for sucking or lapping or piercing