breaks off limbs to escape any threat

Size
Length: 1–2 cm
Lifespan
2–3 years
Diet
Plankton and detritus.
Habitat
Under rocks in intertidal and shallow subtidal zones.
Range
Throughout New Zealand on rocky shores.
Endemism
Native
Main Threats
Habitat disturbance and pollution.
Population
Common in rocky areas throughout New Zealand.
Conservation Status
Not Threatened
Human Risk
harmless
Handling Note
fragile body breaks easily under pressure, handle gently if at all
Conservation Note
Native porcelain crab common on rocky shores throughout New Zealand, not subject to formal NZTCS threat classification.
Te Ao Māori
Porcelain crabs have no specific Māori name. They are small and hidden. Often overlooked. Their fragility is their fame. Breaking easily. Like porcelain. A fitting name. Descriptive. Accurate. They are the delicate jewels of the rock pool. Hidden but beautiful.
It does not fight. It breaks. The Porcelain Crab has fragile limbs. They snap off easily. This is not a defect. It is a strategy. Autotomy. The predator grabs a leg. The leg comes off. The crab escapes. It regrows the limb later. Slowly. Painfully. But it survives. This trade-off defines its life. Fragility for safety. Weakness for strength. It hides under rocks. It filters water. It waits. It does not roam. It does not explore. It stays. It survives. Diet consists of plankton and detritus. It uses feathery appendages to filter food from the water. It is a passive feeder. It does not chase. It does not hunt. It lets the current bring dinner. Efficient. Low energy. Safe. Habitat is the underside of rocks. Intertidal and shallow subtidal. It needs shelter. Exposure means death. Birds see it. Fish see it. Rocks hide it. It clings to the dark. It loves the damp. It fears the sun. Threats include habitat disturbance. Turning over rocks exposes it. Collection by curious humans harms populations. Pollution affects water quality. It is sensitive. It needs clean water. Clear currents. Healthy plankton. Range is nationwide. Found on both main islands. It prefers rocky shores. Sheltered bays. Harbours. It is common. But hidden. You have to look. Under the rock. In the shadow. In the wet. Life span is two to three years. Growth is slow. Moulting is risky. Soft shell means vulnerability. It hides until hardened. Then it returns to the filter. To the flow. To the wait.