Insect making conservationist depart hastily (8)

I believe the answer is:

greenfly

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'insect' is the definition.
(greenfly is a kind of insect)

'conservationist depart hastily' is the wordplay.
'conservationist' becomes 'green' (I've seen this before).
'depart hastily' becomes 'fly' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'green'+'fly'='GREENFLY'

'making' is the link.

Can you help me to learn more?

(Other definitions for greenfly that I've seen before include "Common aphid" , "Garden pest" , "Pests" , "Common aphids" .)

I've seen this clue in The Daily Express.

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