The difference between the sea dragon and the sea dragon fish is that the sea dragon and the seahorse are related and similar in appearance. The shape of a sea dragon is close to that of a fish. According to relevant public information, Hailong is also called Popeye Fish and Sharp-billed Fish. It is a bony fish, which belongs to Syngnathidae in zoological classification. There are more than 150 species of arachnida, and some people say there are 200 species. There are 25 species of sea dragons in China. Sea dragons are related to seahorses. Syngnathidae (Syngnathidae): The body surface is angular or flat, and the tail is slender. A dermoid bone plate, specially treated and hardened. The head is slender and often has a prominent tubular kiss. Small mouth, end position. Toothless. Branchial fissure is very small, located in the back of the head. Branches 4, leaflike. False gills are very developed. Hermaphrodite, the male fish has a sac or bag in the abdomen. The dorsal fin is single and small. The anal fin is very small, usually opposite to the dorsal fin. There are usually pectoral fins. No ventral fins. Whether there is a tail fin or not, the end of the tail fin without a tail is often curled. There are no spines on each fin.