The most venomous known fish is the reef stonefish. It is an ambush predator which waits camouflaged on the bottom.
The beautiful and highly visible lionfish uses venomous barbs around its body as a defence against predators.
The stargazer buries itself out of sight. It can deliver electric shocks as well as venom.
The stinger of a stingray

Venomous fish are species of fish which produce strong mixtures of toxins harmful to humans (called venom) which they deliberately deliver by means of a bite, sting, or stab, resulting in an envenomation. As a contrast, poisonous fish also produce a strong toxin, but they do not bite, sting, or stab to deliver the toxin, instead being poisonous to eat because the human digestive system does not destroy the toxin they contain in their bodies.[1] Venomous fish do not necessarily cause poisoning if they are eaten, as the digestive system often destroys the venom.[1]

There are at least 1200 species of venomous fish, [2][3] with catfishes alone possibly contributing 250–625 species to that total. [4] The former number accounts for two-thirds of the venomous vertebrate population.[5] There are more venomous fish than venomous snakes and indeed more than the combined total of all other venomous vertebrates.[2] Venomous fish are found in almost all habitats around the world, but mostly in tropical waters. Encounters with these species injure over 50,000 people every year.[6]

Venomous fishes carry their venom in venom glands and use various delivery systems, such as spines or sharp fins, barbs, spikes and fangs. The most common venom delivery system is via dorsal spines.[7] Venomous fish tend to be either very visible, using flamboyant colors to discourage predators from attacking them, or skillfully camouflaged and possibly buried in the sand. Apart from the value of improved self defense or capacity to kill prey, venom helps bottom dwelling fish by killing bacteria that could otherwise invade their skin. Few of these venoms have been studied. They are a yet-to-be tapped resource for bioprospecting to find drugs with medical uses.[3]



Striped poison fang blenny can deliver a quick and painful bite.

Venomous fish are very often involved in human injury, usually by accident, but few studies have been done to investigate the constituents of fish venom. Even fewer studies have been done to create antivenom.

The only commercially available antivenom is for the Indo-Pacific stonefish, Synanceja trachynis Stonefish Antivenom (SFAV).[17]

Biological and pharmacological importance of fish venoms

It has been found that the mucous and sting venom of Potamotrygon cf. henlei, a species of stingray that is found in Brazil, is toxic to mice that have nociceptive, edematogenic, and proteolysis activities. Two peptides were isolated from the stingray venom, orpotrin, which causes vasoconstriction, and porflan, which causes inflammation. Knowing how these peptides are structured could lead to the development of a neutralization technique that could effectively act as an antivenom.[18]

Of all the piscine venoms studied, they all produce profound cardiovascular alterations, both in vivo and in vitro. These changes stimulate the release of nitric oxide from the endothelial cells, smooth muscle contractions, and other effects of the atria. Piscine venoms also produce neuromuscular activity effects- depolarization of nerve and muscle cells. In addition, piscine venoms have strong cytolytic activity. In experimental models and in Western immunoblotting analysis, all tested piscine venoms showed structural similarity, which could lead to the advent of an overarching antivenom or other novel uses.[19]

See also


  1. ^ a b Poisonous vs. Venomous fish: What’s the difference? Reef Biosearch. Retrieved 17 July 2009.
  2. ^ a b Smith WL and Wheeler WC (2006) "Venom Evolution Widespread in Fishes: A Phylogenetic Road Map for the Bioprospecting of Piscine Venoms" Journal of Heredity 97 (3):206-217.
  3. ^ a b c d e Grady, Denise Venom Runs Thick in Fish Families, Researchers Learn New York Times 22 August 2006.
  4. ^ Wright, J. J. (2009). "Diversity, phylogenetic distribution, and origins of venomous catfishes". BMC Evolutionary Biology. 9: 282. doi:10.1186/1471-2148-9-282. PMC 2791775. PMID 19961571.
  5. ^ Sivan, Gisha (2009). "Fish venom: pharmacological features and biological significance". Fish and Fisheries. 10 (2): 159–172. Bibcode:2009AqFF...10..159S. doi:10.1111/j.1467-2979.2008.00309.x. ISSN 1467-2979.
  6. ^ Britt, Robert Roy (22 August 2006). "Venomous Fish Outnumber Snakes". LiveScience.
  7. ^ Smith, W. Leo; Stern, Jennifer H.; Girard, Matthew G.; Davis, Matthew P. (2016-11-01). "Evolution of Venomous Cartilaginous and Ray-Finned Fishes". Integrative and Comparative Biology. 56 (5): 950–961. doi:10.1093/icb/icw070. ISSN 1540-7063. PMID 27375272.
  8. ^ Froese, Rainer; Pauly, Daniel (eds.) (2009). "Synanceja verrucosa" in FishBase. July 2009 version.
  9. ^ Wells, Virginia (10 August 2015). "The Stonefish – The Deadliest Fish in The World".
  10. ^ Reef Stonefish, Synanceia verrucosa (Bloch & Schneider, 1801) Australian Museum. Retrieved 21 July 2009.
  11. ^ Froese, Rainer; Pauly, Daniel (eds.) (2009). "Pterois volitans" in FishBase. July 2009 version.
  12. ^ Froese, Rainer; Pauly, Daniel (eds.) (2009). "Uranoscopus sulphureus" in FishBase. July 2009 version.
  13. ^ Taylor, Geoff (March 2000). "Toxic fish spine injury: Lessons from 11 years experience" (PDF). Journal of the South Pacific Underwater Medicine Society. South Pacific Underwater Medicine Society. 30 (1): 7–8. ISSN 0813-1988. OCLC 16986801. Archived from the original on June 10, 2015. Retrieved 10 June 2015.((cite journal)): CS1 maint: unfit URL (link)
  14. ^ Losey GS. 1972. Predation protection in the poison-fang blenny, Meiacanthus atrodorsalis, and its mimics, Ecsenius bicolor and Runula laudandus (Blenniidae). Pac Sci 26(2): 129-139.
  15. ^ Casewell, Nicholas (2017). "The Evolution of Fangs, Venom, and Mimicry Systems in Blenny Fishes". Current Biology. 27 (8): 1184–1191. doi:10.1016/j.cub.2017.02.067. hdl:1887/115463. PMID 28366739.
  16. ^ Wilcox, Christie (March 30, 2017). "Beware the blenny's bite: scientists uncover the toxins in fang blenny venom". Discover.
  17. ^ Gomes, Helena L.; Menezes, Thiago N.; Carnielli, Juliana B. T.; Andrich, Filipe; Evangelista, Karla S.; Chávez-Olórtegui, Carlos; Vassallo, Dalton V.; Figueiredo, Suely G. (2011-06-01). "Stonefish antivenom neutralises the inflammatory and cardiovascular effects induced by scorpionfish Scorpaena plumieri venom". Toxicon. 57 (7): 992–999. doi:10.1016/j.toxicon.2011.04.001. ISSN 0041-0101. PMID 21510970.
  18. ^ Monteiro-dos-Santos, Juliane; Conceição, Katia; Seibert, Carla Simone; Marques, Elineide Eugênio; Ismael Silva, Pedro; Soares, Anderson Brito; Lima, Carla; Lopes-Ferreira, Mônica (2011-09-01). "Studies on pharmacological properties of mucus and sting venom of Potamotrygon cf. henlei". International Immunopharmacology. 11 (9): 1368–1377. doi:10.1016/j.intimp.2011.03.019. ISSN 1567-5769. PMID 21481330.
  19. ^ Church, Jarrod E.; Hodgson, Wayne C. (2002-08-01). "The pharmacological activity of fish venoms". Toxicon. 40 (8): 1083–1093. doi:10.1016/S0041-0101(02)00126-5. ISSN 0041-0101. PMID 12165309.