Spinner Fish

The Spinnerfish is a future fauna species of Subnautica: Below Zero. It was originally designed for the first Subnautica, but has now been repurposed as an Expansion creature.

Appearance
The Spinnerfish has a roughly spherical body with six fleshy protrusions sticking out at 60 degree intervals down the midline. The larger portion of the body is pink and covered with pale-blue patches, with the rest of its body gradually fading out to yellow.

Towards the front of the Spinnerfish, a pair of small eyes with black pupils and blue and green sclerae are visible. And above each eye are three siphons through which water is pumped for movement. Also, the creature seems to lack a mouth entirely.

Behavior
The Spinnerfish is a small herbivorous species with a peculiar method of swimming. Rather than using fins to propel itself through the water, it instead uses three pairs of siphons on either side of its body for jet propulsion. As these jets are angled downwards, the Spinnerfish spins around vertically when moving.

The provided benefit for such a swimming method is currently unknown.

Trivia

 * The Spinnerfish was first shown in the concept art of Subnautica's Sand Shark.
 * The Spinnerfish's appearance was likely inspired by the larval form of the ocean sunfish.