Three‑spined Swimming Crab (Scientific Name: Portunus trituberculatus) is a marine crustacean belonging to the Portunidae family and the Portunus genus. Commonly known as Jinmen Shizi, White Crab, White‑Flowered Crab, Sea Crab, and more.

The cephalothorax is broad and robust, with long spines along both sides, giving it a slightly fusiform shape; its color is dark purple, mottled with bluish‑white markings. The chelipeds are elongated, and the fourth pair of walking legs is flattened like oars, perfectly adapted for swimming.