The Chinese name is the scaled diagonal crab, also known as the reef flat or white bottom crab. It belongs to the genus of diagonal crabs in the order Decapoda of the phylum Arthropods in the animal kingdom. It is a marine organism. The head and chest armor of the scaled diagonal crab is nearly circular, with a width of about 5.5 centimeters, slightly larger than its length. There are two deep cracks on the forehead, and a concave groove in the middle of the central protrusion. There are many particles of different sizes and flat particles resembling scales scattered on the head and chest armor. The particles are surrounded by fine short bristles, and there are a total of four spines on the anterior edge including the posterior spines of the eyes. The ventral surface has smooth steps and feet without horizontal stripes.