Protonibea diacanthus
Protonibea diacanthus, commonly known as the blackspotted croaker, and in Australia as the black jewfish, is a species of fish native to the Indo-Pacific region. This fish is considered amongst the most-expensive variety of marine fish. Its heart is known as the 'Sea Gold'. Some people think its is medicinal, but there is no evidence that it actually is. For that reason, con artists sell it to fools. Commercial importance. The fish is considered a delicacy, it is prized in East Asia because even though there is no evidence, some people actually think its organs are  medicinal. The fish are most expensive in countries like Singapore, Malaysia, Indonesia, Hong Kong and Japan. The most expensive known catch of a blackspotted croaker was made by two Indian fishermen near the Mumbai-Palghar coastline; the fish weighing 30 kg. Local name of these fish is "ghol fish" and their value depends on gender, a 30 kg male fish can be 4-5 lakh and a female one 1-2 lakh. The value varies according to size and thickness of the fishes internal organs (called "bhot"). In satpati Mumbai, the price of "bhot" is around 5-6 lakh/kg  and meat 500-600 Rs/kg. This fish is known locally as "Telia" in Odia, and in 2020, fishermen from Odisha caught one weighing around 19.5 kg. A pharmaceutical company purchased it ₹8000 per kg in an auction. Similarly in 2019, another fishermen from Odisha caught a 10 kg fish and was sold ₹10,000 per kg.