This majestic creature is a type of seahorse found in the coastal waters of southern and western Australia. The Leafy Sea Dragon is an incredible sight to behold, with its long, leaf-like appendages that help it blend in with its surroundings. It is a master of camouflage
From Wikipedia
The leafy seadragon or Glauert's seadragon, is a marine fish. It is the only member of the genus Phycodurus in the family Syngnathidae, which includes seadragons, pipefish, and seahorses.