HomeMarine aquarium fishSeahorses & pipefishThorny seahorse Thorny seahorse (Hippocampus histrix) Scientific name: Hippocampus histrix Kaup, 1856 The Thorny seahorse (Hippocampus histrix) is a marine fish of the family Syngnathidae. BiologyA rare inhabitant of shallow sheltered reefs, found among clumps of algae or in seagrass beds. Large adult pelagic and probably associated with drifting debris. Associated with sponges and sea-squirts. Ovoviviparous. The male carries the eggs in a brood pouch which is found under the tail. Use in traditional Chinese medicine is increasing with the rise in patent medicines. Not common in the aquarium trade.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameHippocampus histrixFamilySyngnathidae (Pipefishes and seahorses)OrderSyngnathiformes (Pipefishes and Seahorses)ClassActinopterygii (Ray-finned fishes)Maximum length17.0Depth range82 m (269 ft)EnvironmentMarine; reef-associated; non-migratory; depth range ? - 82 mClimateTropicalDistributionIndo-Pacific: Tanzania and South Africa to Hawaii and Tahiti, north to Japan, south to New Caledonia. Reported from the Arafura Sea. This name is used for at least four distinct species. International trade is monitored through a licensing system (CITES II, since 5.15.04) and a minimum size of 10 cm applies.Conservation status (IUCN)Data deficient (DD)Threat to humansHarmlessUsesFisheries: highly commercial; aquarium: commercialResilienceHigh, minimum population doubling time less than 15 months (Preliminary K or Fecundity.) More seahorses & pipefishMessmate pipefishCorythoichthys haematopterusScribbled pipefishCorythoichthys intestinalisSchultz's pipefishCorythoichthys schultziAlligator pipefishSyngnathoides biaculeatusTiger tail seahorseHippocampus comesBarbour's seahorseHippocampus barbouriSee all seahorses & pipefish SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026