Gyrodactylus salaris

Gyrodactylus salaris
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Platyhelminthes
Class: Monogenea
Order: Gyrodactylidea
Family: Gyrodactylidae
Genus: Gyrodactylus
Species:
G. salaris
Binomial name
Gyrodactylus salaris
Malmberg, 1957
A warning sign in Scotland

Gyrodactylus salaris, commonly known as salmon fluke,[1] salmon killer, or the Norwegian salmon killer is a tiny monogenean ectoparasite which lives on the body surface of freshwater fish.[2] This leech-like parasite has been implicated in the reduction of Atlantic salmon populations in the Norwegian fjords.[3] It also parasitises other species, including rainbow trout.[4] G. salaris requires fresh water,[2] but can survive in brackish water for up to 18 hours.[5]

The parasite is 0.5 mm (0.02 in) long,[2] and cannot be seen with the naked eye, but it can be seen with a magnifying glass.[6] On its posterior end is a haptor, a specialized organ for attaching to the host fish, which has sixteen hooks around its edge.[2] The parasite is viviparous, that is, it produces live offspring.[7] The parasites give birth to live young nearly as big as themselves and at this time, a further generation is already growing inside the neonates.[4]

  1. ^ Minchin, Dan (7 January 2008). "Gyrodactylus salaris" (PDF). DASIE: Delivering Alien Invasive Species Inventories for Europe. Archived from the original (PDF) on 24 December 2017. Retrieved 2017-11-05.
  2. ^ a b c d Cain, Kenneth D.; Polinski, Mark P. (2014). "Chapter 3. Infectious diseases of coldwater fish in fresh water. Gyrodactylosis". In Woo, Patrick T.K.; Bruno, David W. (eds.). Diseases and disorders of finfish in cage culture (2nd ed.). CABI. pp. 95–96. ISBN 9781780642079.
  3. ^ C.Michael Hogan. 2011. Norwegian Sea. Encyclopedia of Earth. Eds. P.Saundry & C.J.Cleveland. National Council for Science and the Environment. Washington DC
  4. ^ a b "Notifiable diseases : Gyrodactylus salaris". Scottish Government. 8 December 2009. Retrieved 2017-11-05.
  5. ^ Hopkins, CCE (2002). "Introduced marine organisms in Norwegian waters, including Svalbard. Parasites and diseases". In Leppäkoski, Erkki; Gollasch, Stephan; Olenin, Sergej (eds.). Invasive Aquatic Species of Europe. Distribution, Impacts and Management. Dordrecht: Springer Netherlands. pp. 251–252. ISBN 9789401599566.
  6. ^ "Do not spread salmon parasite Gyrodactylus salaris" (PDF). Finnish Ministry of Agriculture and Forestry. Archived from the original (PDF) on 30 August 2005. Retrieved 11 November 2010.
  7. ^ Shoemaker, Craig; Xu, De-Hai; LaFrentz, Benjamin; LaPatra, Scott (2015). "Chapter 1: Overview of fish immune system and infectious diseases. Monogenetic trematodes". In Lee, Cheng-Sheng; Lim, Chhorn; Gatlin, Delbert M. III; Webster, Carl D. (eds.). Dietary Nutrients, Additives, and Fish Health. Wiley-Blackwell. p. 16. ISBN 978-0-470-96288-6.