There are over 50 species of seahorse making up the Hippocampus genus of fish. I know of at least four species found around Singapore (but there could be more): Tiger tail seahorse, Common seahorse, Hedgehog seahorse, and Low-crowned seahorse.
Seahorses are used in Traditional Chinese "Medicine", which helps account for their current vulnerability world-wide from over-harvesting. They are also sold dried as souvenirs and harvested for the aquarium trade, where most die before reaching an aquarium and many die soon afterward.
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