Japan, the world's biggest consumer of prawns, has just seen the advent of a burger now stuffed with the crustaceans served at McDonald's.

Joining a new line-up this month that includes mixed berry yoghurts and chicken salads, the Ebi Filet-O (prawn fillet) burger has been launched in a bid to bring back customers McDonald's Japan has lost.

Similar in size and texture to the existing Fillet-O-Fish, the new burger is selling at ¥270 (US$2.31) in stores across the nation. Prawns are a common item on the Japanese menu and as demand is so high, prawns are lower in price in Japan than the west.