Fauna
Species

Thorny Seahorse

Hippocampus histrix

Also known as Spiny Seahorse, Thorny-Spined Seahorse

Thorny seahorses are easily recognized by the sharp, prominent spines covering their bodies and the long, slender snout they use to suck up tiny prey. These masters of camouflage cling to sea grasses, soft corals, and sponges using their prehensile tails, blending seamlessly into their reef habitats. Like other seahorses, males carry the developing eggs in a specialized brood pouch until they hatch as fully formed miniature seahorses.

MarineCamouflaged
Thorny Seahorse reference
"Thorny Seahorse" by prilfish is licensed under CC BY 2.0. To view a copy of this license, visit https://creativecommons.org/licenses/by/2.0/. · cc-by
—observations
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VulnerableConservation statusIUCN Red List categoriesLCNTVUENCREWEXVulnerableRed List categories, explained →
Key facts
Diet & preyCopepods, Mysid shrimp, Larval fish
Predators
  • Crabs
  • Rays
  • Larger predatory fish
ThreatsBycatch in commercial fisheries, habitat destruction, and overharvesting for traditional medicine and the aquarium trade
HabitatsCoral reefs, seagrass beds, and muddy estuaries in the Indo-Pacific
Life span2 to 4 years
Classification
  1. FamilySyngnathidae
  2. SpeciesHippocampus histrix
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Safe to observe at a normal distance.
What to notice
Look for a slender seahorse covered in long, sharp spines with dark tips and a very long snout.
Support conservation
Observe quietly without touching or disturbing the surrounding coral and seagrass where they anchor.
Responsible observation
  • Maintain distance: Avoid touching or crowding seahorses, as stress can weaken their immune systems.
  • Avoid flash photography: Bright flashes can startle these sensitive fish and disrupt their natural behaviors.
  • Watch the tail: Look for their prehensile tails anchored to soft corals or seagrasses to spot them.
Related species
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