Mary, Mungo and this insect? (5)

I believe the answer is:

midge

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'insect?' is the definition.
(midge is a kind of insect)

I can't explain the remainder of the clue.

(Other definitions for midge that I've seen before include "Dipterous insect, in swarms by water" , "Small flying insect" , "Small, gnat-like fly" , "Small swarming biting insect" , "Tiny swarming insect" .)

I've seen this clue in The Sun.

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