Sturgeons are one of the oldest families of fish but are amongst the world's most threatened animal group.

A type of caviar in Japan comprised of the rare fish sturgeon is selling for $105 per 20 grams.

Nikkei reports that the caviar can be found in Miyazaki Prefecture, on the southern main island of Kyushu.

The area began farming sturgeon fish in 1983 and released its first caviar products in 2013. Miyazaki Caviar 1983 Premium, which can be bought at Japan Caviar, is priced at 12,000 yen ($105) per 20 grams. The unique caviar is aged in rock salt and is offered at French restaurants and department stores in Japan.

The caviar prizes itself on its freshness. Imported caviar is often pasteurized to ensure shelf life.

Japan Caviar began exporting its caviar to Hong Kong and will export to China and the rest of Southeast Asia. The company hopes to double its production from last year to 500kg.

Sturgeons are one of the oldest families of fish but are amongst the world’s most threatened animal group. The fish are native to the Caspian Sea and are prized for their roe. The rare fish group are also prized because they have a kidney, resulting in their flesh not smelling of ammonia.

Choshu Industry, a Yamaguchi Prefecture-based company, began sturgeon farming a year ago. Its aquafarm has 400 black sturgeons and hopes to add 1,000 young sturgeons annually. The company will start selling caviar in Spring 2018.

The town of Bifuka in Hokkaido also hopes to increase revenue from its sturgeon fish. Its current sturgeon aquarium attracts 10,000 visitors per year.

“We want to make sturgeon farming a source of revenue,” said Tetsuya Konno, a town official. “We want to join hands with local restaurants to make Bifuka a place to eat, see and enjoy these fish.”