The flat-billed, round-bodied fish in the sea is the longnose sturgeon.

Longnose sturgeon is a genus of fish in the family Longnose Sturgeon. Maximum total length can be more than 180 centimeters, weighing more than 37 kilograms. Body long pike-shaped, pectoral fins in front of the flat, the rear part of the slightly lateral compression. The head is longer, and the head length is more than half of the body length. The muzzle is extended and paddle-shaped, flattened, broad in front and narrow in back. Eyes very small, oval, lateral. The mouth is inferior, with a large slit.

Habits:

The longnose sturgeon feeds primarily on zooplankton, and occasionally on food such as larvae of rockhopper mosquitoes. The Longnose Sturgeon utilizes its gill rakers to effectively filter feed on zooplankton and other bait from the water. The longnose sturgeon swims continuously in the water, and a steady stream of bait from the water goes in through the open mouth and into the digestive tract through the gill rakers. In the early juvenile sturgeon stage, with the same kind of phenomenon.