Sevruga caviar as saltier, but it can vary depending on the origin of the fish. The caviar is packaged and sold in red tins. A rare type of caviar known as Imperial Caviar, from the Sterlet sturgeon (Acipenser ruthenus), a now nearly extinct species of sturgeon from the Caspian Sea, is sometimes incorrectly labeled as Sevruga, as well as the even rarer Golden Caviar from the albino Sterlet, the caviar being yellow in color. “Pressed sevruga caviar” can also be found, made of a blend of Osetra and Sevruga caviar that has been heated in a saline solution. Sevruga caviar Sevruga caviar
USS Sterlet (SS-392) gun. On 31 October, she made a night surface attack on a tanker previously damaged by and apparently sank it with a spread of six torpedoes. "Sterlet" then joined "Trigger" in escorting the damaged into Saipan. From there, "Sterlet" put to sea on 10 November with six other submarines in a coordinated attack group. On the night of 15 November, she, "Trigger", and engaged in a gun duel with an enemy sub chaser. "Sterlet" completely depleted her supply of five-inch (127 mm) shells in the battle and was forced to sink the enemy craft with torpedoes early the following morning.