Mud shrimp live on clayish sea floors. They are found a lot on the Oystergrounds in the North Sea. The right claw is substantially larger than the left. 'Castle prawn' is perhaps a good name for this animal because it digs complicated systems of passages and rooms, down to 81 centimeters deep in the sea floor. Because mud shrimp live so deeply buried in the ground, there is little known about this animal. Oyster fishermen are not happy if this shrimp is found on oyster banks. Their digging makes the banks unstable.