The owner of a Leicestershire fish and chip shop has admitted selling imported freshwater fish as cod after random DNA tests by trading standards.
River cobbler, farmed extensively in South East Asia, is frozen and sent to the UK and costs half the price of cod.
Balbir Singh Bachra, 51, of the Trident Fish Bar in High Street, Market Harborough, appeared at the town's magistrates earlier.
He was fined £750 and ordered to pay£450 costs with a £15 victim surcharge.
He pleaded guilty to selling food not of the nature demanded by the purchaser.
Trading standards officers in Leicestershire undertook the random tests earlier this year after colleagues in Worcestershire alerted them.
Phil Hurford, of Leicestershire County Council's trading standards, said: "Customers who have ordered and paid for cod should not be deceived into paying the same price for a cheaper alternative.
"If the river cobbler had been described as fish, there would have been no problem."