| Feature | Details |
|---|---|
| Species | Megamya sudacna ("great clam that bites") |
| Category | Molluscs |
| Type | Anchored |
| Attitude | Aggressive |
| Biome | Dolerite Spires |
| Scan Tool | Bioscanner |
The Great Jaw is an enormous and anchored lifeform, containing various Fragments and Raw Materials inside.
Appearance
The Great Jaw is comprised of two domed halves of an enormous shell with a rough and irregular exterior texture. The upper portion forms jagged tooth-like projections that interlock when the shell is closed.
The interior flesh is blue at the top and transitions to purple toward the base, where a great number of eyes of varying sizes are situated. In the center of the body is a stalk projecting upwards, topped with a hollow structure surrounded by fleshy tendrils.
The single Great Jaw present in the game is approximately 62m tall. When its jaw is open, it is approximately 72m wide.
Behavior
The Great Jaw is an enormous ambush predator that functions somewhat like an enormous Venus flytrap. When one of the Great Jaw's sensory structures in its core is triggered, it will open its eyes and close its shells to trap prey within. It then excretes neurotoxins to kill the player.
Strategy
An effective way to enter the main structure safely is through the west-side hole by squeezing between the fleshy tendrils.
Location
The Great Jaw is located in the Dolerite Spires on the SW edge of the map at a depth of 100m.
| Coords & Depth | Description | Image |
|---|---|---|
| -345609, 465921 @ 100m | In the Dolerite Spires on the SW edge of the map |  |
Databank Entry
Source: Scan the Great Jaw
Great jaw (tentatively Megamya sudacna, great clam that bites you). An enormous omnivorous clam with a dangerous defensive/feeding strategy.
- Clam: Like Earthly bivalves, the great jaw's body consists of two mineral shells connected by powerful adductor muscles. The clam's main body, including its digestive organs, heart, and gills, rests inside the shells.
- Mantle: The mantle (the same body part that forms the outer skin of a squid) secretes a matrix of bioplastics on which the hard calcium carbonate shell grows. The enormous size of the adult great jaw's shell may take decades or centuries to achieve. The interior of the mantle is lined with motion-sensitive eyes.
- Closure reflex: When the tendons of the adductor muscles are disturbed, the shells close, trapping prey inside. The jaw then secretes domoic acid neurotoxin. Projected symptoms: nerve damage, short term memory loss, death.
- Mixed feeding strategy: The great jaw's interior is lined with tiny coral polyps, which feed on sunlight with photosynthetic bacteria. The majority of the great jaw's food probably comes from photosynthesis.
- Lithium pearls: The great jaw bioaccumulates lithium during its growth. Nodules are expelled by the clam's body to prevent nerve interference. Recommend retrieval.
- Youth: The scanned index specimen is relatively young. No upper size limit can be established.
Assessment: Critical source of lithium, but dangerous to dive. Avoid touching tendons. Ensure you have an up to date body scan.
Gallery
In Game
 A view of the Great Jaw's core and eyes.
 A view of the Great Jaw viewed from the north.
 The center, hollow internal structure.
 Great Jaw height measured using beacons.
 Width of Great Jaw with its jaw open measured using beacons.
Other
The Great Jaw in the early access trailer.
Trivia
- The Great Jaw is internally referred to as "Clamthulu" in the files.
- The Great Jaw does not activate in creative mode, despite it opening its eyes when a sensory structure is triggered.
- There is a hidden oyster with googly eyes that uses a model similar to the Great Jaw.
