Anteater cruelly chained (7)
I believe the answer is:
echidna
'anteater' is the definition.
('echidna' can be a synonym of 'anteater')
'cruelly chained' is the wordplay.
'cruelly' indicates an anagram (I've seen this in other clues).
'chained' with letters rearranged gives 'ECHIDNA'.
(Other definitions for echidna that I've seen before include "Insectivorous mammal" , "Australian creature" , "Such a beast" , "Spiny Aus. mammal" , "Spiny egg-laying Australian mammal" .)