Donkey concealed amongst llamas, surprisingly (3)
I believe the answer is:
Here is my best explanation:
'donkey' is the definition.
(I've seen this before)
'concealed amongst llamas surprisingly' is the subsidiary indication.
'concealed' indicates the answer is hidden within the clue.
'ass' can be found hidden inside 'amongst llamas surprisingly'.
(Other definitions for ass that I've seen before include "Donkey or silly person", "Foolish person; animal", "Animal; fool", "Transport for a wise man - or a fool", "Buffoon", "Horse-type animal", "Dipstick", "Moke", "An American backside" and "Braying creature".)