Riflemen sick after catching a bug (4,5)

I believe the answer is:

leaf miner

'bug' is the definition.
(I know that leaf miner is a type of bug)

'riflemen sick after catching a' is the wordplay.
'sick' indicates an anagram.
'after catching' means one lot of letters goes inside another.
'riflemen' with letters rearranged gives 'lefminer'.
'lefminer' going around 'a' is 'LEAF MINER'.

I've seen this clue in The Independent.

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