Gonyaulax

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Red tide off the coast of La Jolla, California.
Gonyaulax
Scientific classification
Domain: Eukaryota
(unranked): SAR
(unranked): Alveolata
Phylum: Dinoflagellata
Order: Gonyaulacales
Suborder: Gonyaulacaceae
Genus: Gonyaulax
Species

Gonyaulax is a genus of dinoflagellates with the type species Gonyaulax spinifera (Claparède et Lachmann) Diesing. Gonyaulax belongs to red dinoflagellates and commonly causes red tides.[4]

Structure[edit]

Gonyaulax is a genus of dinoflagellates that are aquatic organisms that with two separate flagella, each having characteristics of both a plant and animal organism. These algae have two separate flagella: one flagella extends backward, and the other wraps around the cell in a lateral groove helping to keep the organism afloat by creating rotational swimming.[5] The plate formula in the genus Gonyaulax Diesing was redefined as Po, 3', 2a, 6", 6c, 4-8s, 5'", 1p, 1"".[6]

Classification[edit]

All species are marine, except for one freshwater species Gonyaulax apiculata.[6]

It previously included several species, which are now considered to belong to a separate genus, e.g.:[6]

Adaptations[edit]

Gonyaulax dinoflagellates has evolved a type of resting spore, a resting cyst, to enable it to survive harsh weather conditions. Resting cysts can be formed when temperature or salinity changes in the surrounding water. These cysts are round mucous covered bodies that gain a reddish color. This color helps to form the Red Tide as further described. Gonyaulax catenella has been recorded forming vegetative cysts in response to cold water.[7]

Reproduction[edit]

Gonyaulax species will reproduce in long chains of protists, especially when faced with turbulent water conditions. These chains allow for clustering of organisms for increased mating, and protection of weak swimming organisms that could otherwise be washed away.[7]

Effect on Humans[edit]

Although Gonyaulax is predominantly found in seawater, it can also have a detrimental effect on humans. Filter feeding organisms e.g. mussels, clams etc. can accumulate these dinoflagellates in their bodies. When humans eat these shellfish after dinoflagellate accumulation during Red Tide season, usually during the warmer months of the year, it can poison the person who eats it.[5]

Red Tide[edit]

Red tide is a discoloration of the sea water that the Gonyaulax species inhabit. These are typically caused by the dinoflagellate species. Red tide is a toxic event that can kill any type of underwater creature that comes in contact with it. The Red Tide effect that is caused by the reproduction of many dinoflagellates contains some of the most toxic poisons known to date. For example, Gonyaulax spinifera has been related to production of yessotoxins (YTXs), a group of structurally related polyether toxins, which can accumulate in shellfish and can produce symptoms similar to those produced by paralytic shellfish poisoning (PSP) toxins.[8] Red Tide and PSP are both caused by ingestion of dinoflagellates and their toxins.

References[edit]

  1. ^ syn. G. schuettii Lemmermann 1899 AQUASYMBIO: Gonyaulax polygramma
  2. ^ syn. Steiniella fragilis Schütt AQUASYMBIO: Gonyaulax fragilis
  3. ^ K. Mertens et al.: Relationship between the dinoflagellate cyst Spiniferites pachydermus and Gonyaulax ellegaardiae sp. nov. from Izmir Bay, Turkey, and molecular characterization, in: Journal of Phycology 51(3), April 2015; doi: 10.1111/jpy.12304
  4. ^ Rollo, Franco; Sassarolil, Stefano; Boni, Laurita; Marota, Isolina (1995-04-28). Molecular typing of the red-tide dinoflagellate Gonyaulax polyedra in phytoplankton suspensions, in: AQUATIC MICROBIAL ECOLOGY (Aquat microb Eco 9) (PDF). 9. Camerino, Italy. p. 55. Retrieved 2015-04-25. ; doi:10.3354/ame009055
  5. ^ a b "Gonyaulax | dinoflagellate genus". Encyclopedia Britannica. Retrieved 2017-04-13. 
  6. ^ a b c Dodge J.D. 1989. Some revisions of the family Gonyaulacaceae (Dinophyceae) based on scanning electron microscope study. Bot. Mar. 32: 275-298.; doi:10.1515/botm.1989.32.4.275
  7. ^ a b "Gonyaulax Adaptations". bioweb.uwlax.edu. Retrieved 2017-04-13. 
  8. ^ Kirkpatrick, Barbara; Fleming, Lora E.; Squicciarini, Dominick; Backer, Lorrie C.; Clark, Richard; Abraham, William; Benson, Janet; Cheng, Yung Sung; Johnson, David (2004-04-01). "Literature review of Florida red tide: implications for human health effects". Harmful Algae. 3 (2): 99–115. PMC 2856946Freely accessible. PMID 20411030. doi:10.1016/j.hal.2003.08.005. 

Further reading[edit]

  • White, A W (Jan 1981). "MARINE ZOO PLANKTON CAN ACCUMULATE AND RETAIN DINOFLAGELLATE TOXINS AND CAUSE FISH KILLS". ASOL Limnology and Oceanography. 26 (1): 103–109. JSTOR 2835810. 
  • Diaz, Patricio; Molinet, Carlos; Seguel, Miriam; Labra, Gissela; Figueroa, Rosa (December 2014). "Coupling planktonic and benthic shifts during a bloom of Alexandrium catenella in southern Chile: Implications for bloom dynamics and recurrence". Harmful Algae. 40 (1): 9–22. doi:10.1016/j.hal.2014.10.001.