Ankle bones (6)
'ankle bones' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for tarsi that I've seen before include "Bones of the ankles and heels" , "collections of bones?" , "Foot bones" , "Ankle bones" , "parts of leg" .)
(Other definitions for tarsus that I've seen before include "Group of bones" , "The seven bones of the upper foot and ankle" , "Arrangement of bones" , "City of which St Paul was a native" , "Saul of ......" .)