Sea horses and pipefishes

Scientific name : Syngnathidae

Ever seen a sea horse? No wonder if for many the answer will be "never". Seahorses and pipefishes are becoming rare for different reasons (see at the bottom of this page). Even where there are many, to see them is not easy: they are small, cryptic, often they live in environments (lagoons, bays) where normally people do not dive.
Notwithstanding the difficulties in meeting them (or maybe even for this reason) sea horses are very popular amongs divers, for their beauty, for their strange shape (they are fishes, even if it is hard to believe), for the life history.
They belong to the class bony fishes, and to the Syngnathiformes order. They are small fishes, thin, elongate, encased in rings of bony plates. Main feature is to have the jaws united together in a pipe snout, with terminal teethless mouth. This gives the typical horse like look, especially in sea horses, when they stand with head bent forward.
Compared with the typical fish anatomy, deviations are striking. Gills opening is only a small pore. Mouth is pipe shaped, teethless. Pelvic fins are missing, anal and caudal fins very small or missing. The tail, long and articulate, is prehensile in many species. Head very mobile, with a neck.
During swimming, propulsion is given by dorsal fin movement, with the participation of the pectoral fins.
Reproduction system is unique: during mating, eggs are passed to the male, that will incubate them in a ventral breeding pouch in seahorses, or simply attached to belly and tail in pipefishes.
Most species living in coastal shallow water, in lagoon or bay. Feeding on small crustaceans, that are sucked through the tubular snout and swallowed. Snout muscles create a depression into the tube, and when the mouth is opened the prey is literally sucked. Poorly mobile, they live in monogamic pairs that can stay together for all the life.
Pipe fishes can resemble the close families of trumpet fishes and cornet fishes. The general shape, the position of fins and the smaller size are the main differences.
Many singnathid species are threatened due to human activities in their environment and overfishing. The main reasons for them being collected are the sale as curio and their use in traditional Chinese medicine as a tonic, to delay skin's and some glands'ageing. A secondary interpretation, attributing to seahorses an aphrodisiac power (not real), could lead them to extintion.
In the last few years, many pygmy sea horses species has been discovered, particularly in Indonesia. Some species' description is still in progress. For further details go to our species list.