Almost all foodstuff taken from tree! Little monkey! (7)
I believe the answer is:
tamarin
'little monkey' is the definition.
(tamarin is a type of monkey)
'almost all foodstuff taken from' is the wordplay.
'almost all foodstuff' becomes 'tamar' (I can't explain this - if you can you should give a lot more credence to this answer).
'taken' is a charade indicator (letters next to each other).
'from' becomes 'in' (I've seen this in other clues).
'tamar'+'in'='TAMARIN'
'tree' is the link.
I am not very happy about this link. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for tamarin that I've seen before include "Small monkey of the marmoset family" , "Main art (anag) - monkey" .)