Ornament showing mammal rolling over captured by worker (6)
I believe the answer is:
anklet
'ornament' is the definition.
(anklet is a kind of ornament)
'mammal rolling over captured by worker' is the wordplay.
'mammal' becomes 'elk' (elk is a kind of mammal).
'rolling over' is a reversal indicator.
'captured by' indicates putting letters inside.
'worker' becomes 'ant' (worker is a type of ant).
'elk' backwards is 'kle'.
'kle' going inside 'ant' is 'ANKLET'.
'showing' acts as a link.
(Other definitions for anklet that I've seen before include "Band worn on leg" , "footwear" , "leg chain" , "Ornamental chain" , "Leg decoration" .)