1. The tail characteristics are unclear; please refer to the picture for verification. The family Rajidae, genus Raja, belongs to the cartilaginous fish and has many species.2. The following image shows Raja porosa, commonly known as the boss fish, Laoban fish, Huazi fish, or cauldron cover fish. The body disc is slightly round or squarish, with an average body length of 30 to 50 centimeters. The disc width is greater than the length, and the weight ranges from 1000 to 5000 grams.3. The tail is flat and elongated, with well-developed pectoral fins. The snout is medium in length, with the tip protruding. In juveniles and females, the leading edge is slightly undulated, and the snout is slightly protruding; in males, the undulation of the leading edge is more significant, and the snout is significantly protruding.4. The eyes are small and elliptical, with the length of the snout being 3.6 to 4.4 times the diameter of the eye. The blowhole is located behind the eye. The anterior nostril is wide and extends to the lateral side of the snout, while the posterior nostril is half-ring shaped and prominent on the lateral side, forming the inlet nostril.5. The mouth is relatively large and horizontal; the teeth are fine and numerous, arranged in a paving stone pattern. The male teeth are sharp, while the female teeth are smooth. This type of fish habitats in colder sea areas with sandy bottoms, often partially buried in sand, exposing only the eyes and blowholes. They rest during the day and are active hunters at night.6. The main food includes crabs, shrimps, and other crustaceans, mollusks, and small fish. Their breeding method is oviparous, with 1 to 2 young born at a time, followed by rest and another pregnancy within one to several days.7. The eggshell is flat and rectangular, with angular projections at the four corners, densely covered with thread-like sticky strips, attached to algae, fragmented shellfish, or rocks. The young fish measure about 9 centimeters in length after hatching.8. They are distributed in the western North Pacific Ocean, the East China Sea, the South China Sea, the Yellow Sea, and the Bohai Sea, but the yields are not concentrated, and the fishing season is not obvious. They are usually caught together with other fish.9. If the tail is pointed and flat, it may belong to the Dasyatidae family, the Dasyatis genus, which includes fish known as the stingray. The image below shows the smooth stingray Dasyatis akajei, commonly known as the smooth river stingray, red bass, or yellow skate.