Tree-dweller in shade endlessly (5)
I believe the answer is:
orang
'tree-dweller' is the definition.
(animal that lives in trees)
'shade endlessly' is the wordplay.
'shade' becomes 'orange' (orange is a colour).
'endlessly' means to remove the last letter.
'orange' with its last letter taken off is 'ORANG'.
'in' acts as a link.
(Other definitions for orang that I've seen before include "Forest-dweller with red hair" , "Large ape" , "Primate" , "- - -utan" , "Short tree-dweller" .)