Hiding in Mexico, a timid American mammal (5)
I believe the answer is:
coati
'american mammal' is the definition.
(I've seen this before)
'hiding in mexico a timid' is the wordplay.
'hiding' says the answer is hidden in the clue.
'COATI' can be found hidden inside 'in mexico a timid'.
(Other definitions for coati that I've seen before include "Furry animal" , "beast" , "omnivorous mammal" , "Tropical animal" , "Flesh-eating mammal" .)