Seahorse

 The seahorse (genus Hippocampus) is a true, albeit strange-looking, fish.  It shares the family Syngnathidae with the pipefish.  Like other fish, it breathes through gills.  But it lacks scales.  Its skin is stretched over a series of interlocking bony plates, which are arranged in rings for the length of its body.  Each species of seahorse has a distinctive number of rings.  Also unlike most other fish, the seahorse swims upright and has a neck separating the head from the main portion of its body.  The seahorse has a dorsal fin and pectoral fins, but no caudal fin.  It is a very poor swimmer, spending most of its life in seagrass beds, coral reefs, mangroves, or estuaries in shallow tropical or temperate waters.  Recently, a small colony of seahorse was found in the Thames estuary of Britain.  They have prehensile tails, used to attach themselves to seagrass or other items on or near the seabed.  Like a few other animals, the male has a major role in the reproduction cycle.  The female lays her eggs in the male’s brood pouch.  The male carries the eggs (up to 1,500) for nine to 45 days depending on the species.  The new seahorses emerge fully developed, but tiny.  They are immediately on their own as neither parent has a further role in their life.  The tiny new seahorses drift in the current, feeding and avoiding being eaten as they can until large enough to settle into the adult life pattern.  Because the seahorse is small and blends well into its surroundings, it is little-studied.  Population size is unknown.  Seahorses eat very small crustaceans and, in turn, are eaten by larger fish.  Humans harvest them either for ornaments, for aquariums, or for use in oriental medicine.  The most significant threat to seahorse though is habitat loss.