Two chess pieces caught right crustacean (4,5)
I believe the answer is:
king prawn
'crustacean' is the definition.
(I've seen this before)
'two chess pieces caught right' is the wordplay.
'two chess pieces' can mean two replacements for 'chess piece'.
'chess piece' becomes 'king' (king is a kind of chess piece).
'chess piece' becomes 'p' (abbreviation for Pawn).
'caught right' becomes 'rawn' (I can't justify this - if you can you should believe this answer much more).
'king'+'p'+'rawn'='KING PRAWN'
Can you help me to learn more?
(Other definitions for king prawn that I've seen before include "crustacean" , "Piece of seafood" , "(Regal?) seafood" .)