The genus Hippocampus contains more than 70 species found mostly in shallow tropical and temperate marine and estuarine waters throughout the world. About 30 species are known from Australian waters.
Seahorses are masters of camouflage and live in seagrass meadows, macroalgal beds, sponge gardens, coral and rocky reefs and mangrove areas. They use their prehensile tail to cling to leaves, algal fronds, sponges and other structures.
Like all members of the family Syngnathidae, they have a tiny mouth at the end of a tubular snout, and bodies encased in bony plates that are arranged in rings. Video of a dwarf seahorse catching copepods.
Species share the following characteristics: head at an angle to the body, a deep compressed abdomen, a well-defined flexible neck, a prehensile tail without a caudal fin, the dorsal fin much closer to the head than to the tip of the tail, and a coronet or group of spines on top of the head. Video How the seahorse got its shape.
Sseahorses and pipefishes have a unique reproductive system, where the male incubates developing embryos in a specialized brooding structure in which they are aerated, osmoregulated, protected and likely provisioned during their development - akin to other forms of viviparity (Stölting & Wilson 2007).
Seahorses swim upright using their dorsal and pectoral fins for propulsion. Most species feed on tiny crustaceans sucked in through their tiny mouths.
Hippocampus is from the Greek hippos meaning ‘horse’, and campe meaning ‘sea monster’.
Seahorses are protected in many parts of the world. All species are CITES listed and many are listed as threatened on the IUCN Red list of Threatened Species. All Australian species are protected under the EPBC Act 1999 (Environment Protection and Biodiversity Conservation Act). They are also protected in many of the Australian states and territories.
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