The scientific name of the papaya fish is Ostracion cubicus. The small is only 4cm, and the maximum body length is no more than 45cm. The body armor has quadrangular ridges, the dorsal and ventral ribs are well developed, there is no dorsal middle rib, and there is only a slight bulge in front of the dorsal fin. The mouth position is slightly higher, the lip is extremely thick, and there is an obvious lump in the center of the upper lip.

The head and body of the juvenile papaya fish are yellow with a lot of black about the size of the pupil Spots; adults are yellowish-brown to gray-brown, with small black spots scattered on the head, and in the center of each scale of the body armor there is a light blue or white spot with a black edge about the size of the pupil.

The bright colors and spots on the skin of papaya fish are a warning to any potential predator, and when they feel startled, stressed or injured, they quickly release a A neurotoxin (Pahutoxin) unique to boxfish, this hemolytic toxin is present in the mucus on their surface.