Some species of pipefish have prehensile tails, as in seahorses. Included in Syngnathidae are seahorses, the pipefish, and the weedy and leafy sea dragons. They are related to the pipefish and seahorses. Large schools of jacks, giant seahorses and moray eels can also be spotted. Included in Syngnathidae are seahorses, the pipefish, and the weedy and leafy seadragons. Molecular dating finds that pipefish and seahorses diverged during the Late Oligocene. True pygmy seahorses have distinctive morphological markers. In seahorses and pipefish, it is the male that becomes pregnant. Coral reefs and seagrass beds are deteriorating, reducing viable habitats for seahorses. The Syngnathiformes are an order of ray-finned fishes that includes the pipefishes and seahorses. Concerns have also arisen over the use of turtle plastron and seahorses. Scientists at 15 aquaria studied 90 seahorses of three species. Water quality is very important for the survival of seahorses in an aquarium. The enemies range from seahorses to giant octopodes. As with seahorses, the male leafy seadragon cares for the eggs.