Category Archives: Algae

Friday Fellow: Giant Kelp

by Piter Kehoma Boll

This week we’ll stay in the sea and meet on of the most impressive algae, the giant kelp, Macrocystis pyrifera. It is called giant for a good reason, since it can grow up to 50 m in length and form real forests in the sea. Being able to grow 60 cm in a single day, it has the fastest linear growth of any organism on Earth.

The giant kelp is a brown algae, so it is not related (at least not closely) to green or red algae, but it is a relative of the tiny diatoms that cover the ocean. It grows in cold waters along the Pacific Coast of the Americas and close to the coast of the countries near Antarctica, such as Chile, Argentina, South Africa, Australia, and New Zealand.

macrocystis_pyrifera

It’s a really beautiful alga, isn’t it? Photo by California Academy of Sciences.*

This amazing organism is composed by a thallus that branches at the base and then continues as a single and very long stalk from which blades develop at regular intervals on only one side. At the base of each blade, there is a gas  bladder that helps the whole organism to stand in a more or less upright position.

The huge kelp forests in the oceans are an important ecosystem and many species depend on them to survive, including other algae. Humans also use the giant kelp either as a direct food source or as a source of dietary supplements, since the alga is rich in many minerals, especially iodine and potassium, as well as several vitamines.

macrocystis_pyrifera2

The kelp forests sustain a huge diversity of lifeforms in the oceans. Photo by Stef Maruch.**

In the last decades, the kelp populations are decreasing rapidly. This is most likely caused by climatic changes, as this alga cannot develop in temperatures above 21°C. The giant kelp is, thus, just one more victim of global warming. And if it goes extinct, a whole ecosystem will be gone with it.

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ResearchBlogging.orgReferences:

Foster, M. (1975). Algal succession in a Macrocystis pyrifera forest Marine Biology, 32 (4), 313-329 DOI: 10.1007/BF00388989

Wikipedia. Macrocystis pyrifera. Available at . Access on January 19, 2007.

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Friday Fellow: Wheel Necklace Diatom

ResearchBlogging.orgby Piter Kehoma Boll

Most of you likely know what diatoms are, microscopic algae with a silica shell that are very abundant in the world’s oceans and one of the main oxygen producers. You may have seen images like the one below, showing the diversty of diatoms, but can you name a single species?

diatoms

The beautiful, yet largely neglected by non-experts, diversity of diatoms. Photo by Wikimedia user Wipeter.*

Today I decided to bring you a diatom Friday Fellow and let me tell you: it was not at all easy to select a nice species with a considerable amount of available information and a good picture. But at the end the winner of the First Diatom Friday Fellow Award was…

Thalassiosira rotula!

thalassiosira_rotula

Three connected individuals of Thalassiosira rotula. Photo by micro*scope.**

As with most microorganisms, this species has no common name and, as it is a tradition here, I decided to make one up and chose wheel necklace diatom. Necklace diatom seems to be a good common name for species in the genus Thalassiosira, as they are formed by several individuals connected to each other in a pattern that resembles a necklace. I decided to call this particular species wheel necklace diatom because of its specific epithet, rotula, which means little wheel in Latin.

The wheel necklace diatom is a marine species found worldwide close to the coast. It is very abundant and the dominant species in some areas, so it is of great ecological importance. Small planctonic crustaceans, such as copepods, usually feed on the wheel necklace diatom and, as those crustaceans are used as food for much larger animals, the wheel necklace diatom is responsible for sustaining a whole food chain.

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References:

Ianora, A., Poulet, S., Miralto, A., & Grottoli, R. (1996). The diatom Thalassiosira rotula affects reproductive success in the copepod Acartia clausi Marine Biology, 125 (2), 279-286 DOI: 10.1007/BF00346308

Krawiec, R. (1982). Autecology and clonal variability of the marine centric diatom Thalassiosira rotula (Bacillariophyceae) in response to light, temperature and salinity Marine Biology, 69 (1), 79-89 DOI: 10.1007/BF00396964

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Friday Fellow: Witch’s Jelly

ResearchBlogging.orgby Piter Kehoma Boll

I wonder how many people can say they have a bacterium that reminds them of their childhood. Well, at least I can say that I have.

When I was a boy and started to know about the amazing world of living beings that fill our planet, I spent most of my time outdoors looking at every small corner of the backyard and nearby woods in search for interesting lifeforms. And one that always caught my attention was a strange brownish green gelatinous mass that appeared on the ground in the rainy season.

nostoc_commune

Have you ever found something like that on the ground? Photo by flickr user gailhampshire.*

At first I thought it was some species of green alga, but was unable to identify the species. Many years later I finally found out what it is, a colony of cyanobacteria called Nostoc commune and commonly known as star jelly, witch’s butter, witch’s jelly and many other names. It is found worldwide, from the tropics to the polar regions.

As in other cyanobacteria, the witch’s jelly is formed by a colony of unicellular organisms connected in chains. Those are embedded in a gelatinous matrix of polysaccharides that gives the colony its jelly appearance.

nostoc_commune

Chains of Nostoc commune in the matrix of polysaccharides seen under the miscroscope. Photo by Kristian Peters.**

During dry periods, the colonies of witch’s jelly dessiccate and become an inconspicuous thin layer on the ground. They may remain in this state for decades, maybe centuries, until the ideal conditions come back.

In some places, especially Southeast Asia, the witch’s jelly is consumed as food, being a traditional food in the Chinese Lunar New Year.

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References:

Lipman, C. (1941). The Successful Revival of Nostoc commune from a Herbarium Specimen Eighty- Seven Years Old Bulletin of the Torrey Botanical Club, 68 (9) DOI: 10.2307/2481755

Tamaru, Y., Takani, Y., Yoshida, T., & Sakamoto, T. (2005). Crucial Role of Extracellular Polysaccharides in Desiccation and Freezing Tolerance in the Terrestrial Cyanobacterium Nostoc commune Applied and Environmental Microbiology, 71 (11), 7327-7333 DOI: 10.1128/AEM.71.11.7327-7333.2005

Wikipedia. Nostoc commune. Available at: < https://en.wikipedia.org/wiki/Nostoc_commune >. Access on September 19, 2016.

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Friday Fellow: Elegant sunburst lichen

by Piter Kehoma Boll

Bipolar and Alpine in distribution, occurring in both Arctic and Antarctic regions, as well as on the Alps and nearby temperate areas, the elegant sunburst lichen (Xanthoria elegans) is a beautiful and interesting creature. As all lichens, it is formed by a fungus associated with an alga.

An elegant sunburst lichen growing on a rock in the Alps. Photo by flickr user Björn S...*

An elegant sunburst lichen growing on a rock in the Alps. Photo by flickr user Björn S…*

The elegant sunburst lichen grows on rocks and usually has a circular form and a red or orange color. Growing very slowly, at a rate of about 0.5 mm per year, they are useful to estimate the age of a rock face by a technique called lichenometry. By knowing the growth rate of a lichen, one can assume the lichen’s age by its diameter and so determine the minimal time that the rock has ben exposed, as a lichen cannot grow on a rock if it is not there yet, right? This growth rate is not that regular among all populations. Lichens growing closer to the poles usually grow quickly because they seem to have higher metabolic rates to help them survive in the colder climates.

Beside its use to determine the age of a rock surface, the elegant sunburst lichen is a model organism in experiments related to resistance to the extreme environments of outer space. It has showed the ability to survive and recover from exposures to vacuum, UV radiation, cosmic rays and varying temperatures for as long as 18 months!

Maybe when we finally reach a new inhabitable planet, we will find out that the elegant sunburst lichen had arrived centuries before us!

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References:

Murtagh, G. J.; Dyer, P. S.; Furneaux, P. A.; Critteden, P. D. 2002. Molecular and physiological diversity in the bipolar lichen-forming fungus Xanthoria elegans. Mycological Research, 106(11): 1277–1286. DOI: 10.1017/S0953756202006615

Wikipedia. Xanthoria elegans. Available at: < https://en.wikipedia.org/wiki/Xanthoria_elegans >. Access on June 30, 2016.

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The history of Systematics: Animals in Systema Naturae, 1758 (part 4)

by Piter Kehoma Boll

This is the fourth and last part of this series of posts. See here part 1, part 2 and part 3.

I’m presenting here the 6 th and last class of animals: Vermes. It included basically anything that was neither a vertebrate nor an arthropod.

6. Vermes (worms)

Heart with one ventricle and one auricle; cold pus.
Spiracles absent?
Jaws multiple, various.
Penises several in hermaphrodites, androgynous.
Senses: tentacles, head absent (rarely with eyes, no ears and nostrils).
Covering: sometimes calcareous or absent, if not spines.
Support: neither feet nor fins.

Vermes were classified according the form of the body in 5 orders: Intestina, Mollusca, Testacea, Lithophyta and Zoophyta.

6.1 Intestina (internal ones or intestines), simple, naked and without appendages: Gordius (horsehair worms), Furia (the legendary worm), Lumbricus (earthworms and lugworms), Ascaris (roundworms and pinworms), Fasciola (liver flukes), Hirudo (leeches), Myxine (hagfishes) and Teredo (shipworms).

Linnaeus’ heterogeneous order Intestina included (from left to right, top to bottom) the water horsehair worm (Gordius aquaticus), the legendary hell’s fury (Furia infernalis), the common earthworm (Lumbricus terrestris), the giant roundworm (Ascaris lumbricoides), the sheep liver fluke (Fasciola hepatica), the European medicinal leech (Hirudo medicinalis), the Atlantic hagfish (Myxine glutinosa), and the naval shipworm (Teredo navalis). Credits to Jiří Duchoň (horsehair worm), Michael Linnenbach (earthworm), Wikimedia user GlebK (leech), Arnstein Rønning (hagfish), Poi Australia [poi-australia.com.au] (shipworm).

Linnaeus’ heterogeneous order Intestina included (from left to right, top to bottom) the water horsehair worm (Gordius aquaticus), the legendary hell’s fury (Furia infernalis), the common earthworm (Lumbricus terrestris), the giant roundworm (Ascaris lumbricoides), the sheep liver fluke (Fasciola hepatica), the European medicinal leech (Hirudo medicinalis), the Atlantic hagfish (Myxine glutinosa), and the naval shipworm (Teredo navalis). Credits to Jiří Duchoň (horsehair worm), Michael Linnenbach (earthworm), Wikimedia user GlebK (leech), Arnstein Rønning (hagfish), Poi Australia [poi-australia.com.au] (shipworm).

 6.2 Mollusca (soft ones), simple, naked and with appendages: Limax (land slugs), Doris (doriid sea slugs), Tethys (tethydid sea slugs), Nereis (polychaetes), Aphrodita (sea mice), Lernaea (anchor worms), Priapus (priapulid worms and anemones), Scyllaea (scyllaeid sea slugs), Holothuria (salps and man o’ wars), Triton (possibly some sort of sea slug), Sepia (octopuses, squids and cuttlefishes), Medusa (jellyfishes), Asterias (starfishes), Echinus (sea urchins and sand dollars).

Among the animals that Linnaeus put under Mollusca are (from left to right, top to bottom) the leopard slug (Limax maximus), the warty dorid (Doris verrucosa), the fringed tethydid (Tethys leporina, now Tethys fimbria), the slender ragworm (Nereis pelagica), the sea mouse (Aphrodita aculeata), the common anchor worm (Lernaea cyprinacea), the cactus worm (Priapus humanus, now Priapulus caudatus), the sargassum nudibranch (Scyllaea pelagica), the Portuguese man o’ war (Holothuria physalis, now Physalia physalis), the common cuttlefish (Sepia officinalis), the moon jellyfish (Medusa aurita, now Aurelia aurita), and the European edible sea urchin (Echinus esculentus).Credits to Marina Jacob (slug), Wikimedia user Seascapeza (dorid), Pino Bucca (tethydid), Alexander Semenov (ragworms), Michael Maggs (sea mouse), glsc.usgs.gov (anchor worm), Shunkina Ksenia (cactus worm), Universidad de Olviedo (sargassum nudibranch), Hans Hillewaert (cuttlefish, jellyfish and starfish), and Bengt Littorin (sea urchin).

Among the animals that Linnaeus put under Mollusca are (from left to right, top to bottom) the leopard slug (Limax maximus), the warty dorid (Doris verrucosa), the fringed tethydid (Tethys leporina, now Tethys fimbria), the slender ragworm (Nereis pelagica), the sea mouse (Aphrodita aculeata), the common anchor worm (Lernaea cyprinacea), the cactus worm (Priapus humanus, now Priapulus caudatus), the sargassum nudibranch (Scyllaea pelagica), the Portuguese man o’ war (Holothuria physalis, now Physalia physalis), the common cuttlefish (Sepia officinalis), the moon jellyfish (Medusa aurita, now Aurelia aurita), the common starfish (Asterias rubens), and the European edible sea urchin (Echinus esculentus). Credits to Marina Jacob (slug), Wikimedia user Seascapeza (dorid), Pino Bucca (tethydid), Alexander Semenov (ragworm), Michael Maggs (sea mouse), glsc.usgs.gov (anchor worm), Shunkina Ksenia (cactus worm), Universidad de Olviedo (sargassum nudibranch), Hans Hillewaert (cuttlefish, jellyfish and starfish), and Bengt Littorin (sea urchin).

6.3 Testacea (covered with a shell), simple, covered by a calcareous shelter: Chiton (chitons), Lepas (barnacles), Pholas (piddocks and angelwings), Myes (soft-shell clams), Solen (razor clams), Tellina (tellins), Cardium (cockles), Donax (wedge shells), Venus (venus clams), Spondylus (thorny oysters), Chama (jewel box shells), Arca (ark clams), Ostrea (true oysters), Anomia (saddle oysters), Mytilus (mussels), Pinna (pen shells), Argonauta (paper nautiluses), Nautilus (nautiluses), Conus (cone snails), Cypraea (cowries), Bulla (bubble shells), Voluta (volutes), Buccinum (true whelks), Strombus (true conchs), Murex (murex snails), Trochus (top snails), Turbo (turban snails), Helix (land snails), Nerita (nerites), Haliotis (abalones), Patella (limpets and brachiopods), Dentalium (tusk shells) and Serpula (serpulid worms and worm snails).

Linnaeus’ diverse order Testacea included (from left to right, top to bottom): the West Indian green chiton (Chiton tuberculatus), the smooth gooseneck barnacle (Lepas anatifera), the common piddock (Pholas dactylus), the sand gaper (Myes arenaria, now Mya arenaria), the sheath razor (Solen vagina), the sunrise tellin (Tellina radiata), the great ribbed cockle (Cardium costatum), the abrupt wedge shell (Donax trunculus), the wary venus (Venus verrucosa), the spiny scallop (Spondylus gaederopus), the lazarus jewel box (Chama lazarus), the Noah’s Ark shell (Arca noae), the European flat oyster (Ostrea edulis), the European jingle shell (Anomia ephippium), the blue mussle (Mytilus edulis), the rough penshell (Pinna rudis), the greater argonaut (Argonauta argo), the chambered nautilus (Nautilus pompilius), the marbled cone (Conus marmoreus), the tiger cowry (Cypraea tigris), the Pacific bubble (Bulla ampulla), the music volute (Voluta musica), the common whelk (Buccinum undatum), the West Indian fighting conch (Strombus pugilis), the caltrop murex (Murex tribulus), maculated top snail (Trochus maculatus), the tapestry turban (Turbo petholatus), the Roman snail (Helix pomatia), the bleeding tooth nerite (Nerita peloronta), Midas ear abalone (Haliotis midae), the Mediterranean limpet (Patella caerulea), the elephant tusk shell (Dentalium elephantinum), the sand worm snail (Serpula arenaria, now Thylacodes arenarius). Credits to James St. John (chiton), Ruben Vera (barnacle), Valter Jacinto (piddock), Oscar Bos [ecomare.nl] (sand gaper), Guido & Philippe Poppe [conchology.be] (razor), femorale.com (tellin, cockle, scallop, ark shell, jingle shell, bubble, fighting conch, nerite, abalone, tusk shell), Hans Hillewaert (wedge shell, venus, nautilus, whelk), Richard Parker (jewel box, marbled cone), Jan Johan ter Poorten (oyster), Wikimedia user Hectonichus (penshell, volute), Bernd Hoffmann (argonaut), Samuel Chow (cowry), Frédéric Ducarme (turban), H. Krisp (Roman snail), Wikimedia user Esculapio (limpet), Matthieu Sontag (worm snail).

Linnaeus’ diverse order Testacea included (from left to right, top to bottom): the West Indian green chiton (Chiton tuberculatus), the smooth gooseneck barnacle (Lepas anatifera), the common piddock (Pholas dactylus), the sand gaper (Myes arenaria, now Mya arenaria), the sheath razor (Solen vagina), the sunrise tellin (Tellina radiata), the great ribbed cockle (Cardium costatum), the abrupt wedge shell (Donax trunculus), the warty venus (Venus verrucosa), the spiny scallop (Spondylus gaederopus), the lazarus jewel box (Chama lazarus), the Noah’s Ark shell (Arca noae), the European flat oyster (Ostrea edulis), the European jingle shell (Anomia ephippium), the blue mussle (Mytilus edulis), the rough penshell (Pinna rudis), the greater argonaut (Argonauta argo), the chambered nautilus (Nautilus pompilius), the marbled cone (Conus marmoreus), the tiger cowry (Cypraea tigris), the Pacific bubble (Bulla ampulla), the music volute (Voluta musica), the common whelk (Buccinum undatum), the West Indian fighting conch (Strombus pugilis), the caltrop murex (Murex tribulus), the maculated top snail (Trochus maculatus), the tapestry turban (Turbo petholatus), the Roman snail (Helix pomatia), the bleeding tooth nerite (Nerita peloronta), Midas ear abalone (Haliotis midae), the Mediterranean limpet (Patella caerulea), the elephant tusk shell (Dentalium elephantinum), the sand worm snail (Serpula arenaria, now Thylacodes arenarius). Credits to James St. John (chiton), Ruben Vera (barnacle), Valter Jacinto (piddock), Oscar Bos [ecomare.nl] (sand gaper), Guido & Philippe Poppe [conchology.be] (razor), femorale.com (tellin, cockle, scallop, ark shell, jingle shell, bubble, fighting conch, nerite, abalone, tusk shell), Hans Hillewaert (wedge shell, venus, nautilus, whelk), Richard Parker (jewel box, marbled cone), Jan Johan ter Poorten (oyster), Wikimedia user Hectonichus (penshell, volute), Bernd Hoffmann (argonaut), Samuel Chow (cowry), Frédéric Ducarme (turban), H. Krisp (Roman snail), Wikimedia user Esculapio (limpet), Matthieu Sontag (worm snail).

6.4 Lithophyta (stone plants), composite, growing on a solid base: Tubipora (organ pipe corals), Millepora (fire corals), Madrepora (stone corals and Acetabularia algae).

Three species listed by Linnaeus under Lithophyta (from left to right): organ pipe coral (Tubipora musica), sea ginger (Millepora alcicornis), zigzag coral (Madrepora oculata). Credits to Aaron Gustafson (pipe coral), Nick Hobgood (sea ginger), NOAA, U.S.’ National Oceanic and Atmospheric Administration (zigzag coral).

Three species listed by Linnaeus under Lithophyta (from left to right): organ pipe coral (Tubipora musica), sea ginger (Millepora alcicornis), zigzag coral (Madrepora oculata). Credits to Aaron Gustafson (pipe coral), Nick Hobgood (sea ginger), NOAA, U.S.’ National Oceanic and Atmospheric Administration (zigzag coral).

6.5 Zoophyta (animal plants), growing like plants, with animated flowers: Isis (bamboo corals), Gorgonia (sea fans), Alcyonum (soft corals), Tubularia (pipe corals), Eschara (bryozoans and red algae), Corallina (coralline algae), Sertularia (bryozoans and hydrozoans), Hydra (hydras, cilliates and rotifers), Pennatula (sea pens), Taenia (tapeworms), Volvox (volvox algae and amLinebae).

Some species in Linnaeus’ order Zoophyta were (from left to right, top to bottom): the Venus sea fan (Gorgonia flabellum), the dead man’s fingers (Alcyonium digitatum), the oaten pipe hydroid (Tubullaria indivisa), the leafy bryozoan (Eschara foliacea, now Flustra foliacea), the coral weed (Corallina officinalis), the squirrel’s tail (Sertularia argentea), the grooved vorticella (Hydra convallaria, now Vorticella convallaria), the phosphorescent sea pen (Pennatula phosphorea), the pork tapeworm (Taenia solium), and the globe volvox (Volvox globator). Credits to Greg Grimes (sea fan), Bengt Littorin (dead man’s fingers), Bernard Picton (pipe hydroid, sea pen), biopix.com (bryozoan), Lovell and Libby Langstroth (coral weed), National Museums Northern Ireland (squirrel’s tail), D. J. Patterson (vorticella and volvox), Pulich Health Image Library (tapeworm).

Some species in Linnaeus’ order Zoophyta were (from left to right, top to bottom): the Venus sea fan (Gorgonia flabellum), the dead man’s fingers (Alcyonium digitatum), the oaten pipe hydroid (Tubullaria indivisa), the leafy bryozoan (Eschara foliacea, now Flustra foliacea), the coral weed (Corallina officinalis), the squirrel’s tail (Sertularia argentea), the grooved vorticella (Hydra convallaria, now Vorticella convallaria), the phosphorescent sea pen (Pennatula phosphorea), the pork tapeworm (Taenia solium), and the globe volvox (Volvox globator). Credits to Greg Grimes (sea fan), Bengt Littorin (dead man’s fingers), Bernard Picton (pipe hydroid, sea pen), biopix.com (bryozoan), Lovell and Libby Langstroth (coral weed), National Museums Northern Ireland (squirrel’s tail), D. J. Patterson (vorticella and volvox), Pulich Health Image Library (tapeworm).

Linnaeus may have made some mistakes while classifying mammals, birds, amphibians, fishes and insects, but nothing compares to the mess that his class Vermes was. It included animals from many different phyla and even red and green algae! Sometimes the same genus included both animals and plants.

And this concludes our presentation of animals in Linnaeus’ 1758 edition of Systema Naturae.

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References:

Linnaeus. 1758. Systema Naturae per Regna Tria Naturae…

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Friday Fellow: Sailor’s Eyeball

by Piter Kehoma Boll

Once more our Friday Fellow is hidden among the coral reefs. Its name: Valonia ventricosa, commonly known as sailor’s eyeball.

This green shiny alga is one of the largest single-celled organisms, reaching more than 5 cm in diameter. It is found in tropical seas all around the world, usually associated to coral reefs. It has a spheric to oval shape and a shiny dark to light green surface, making it look like a cut gemstone.

A living jewel of the sea,

A living jewel of the sea. Credits to Philippe Bourjon.

Due to its unusually large size for a unicellular organism, the sailor’s eyeball has been extensively studied regarding its cell wall structure, and it seems to be quite peculiar. The cellulose fibers in its cell wall, which is almost as thick as the cytoplasm, are arranged in a complex structure, including parallel and crossing fibers, as well as some strange fiber swirls with no known function. Its membranes do not seem to have any aquaporines, i.e., pores for letting water go through.

On your next visit to a coral reef, try to find some!

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References:

Eslick, E. M.; Beilby, M.J.; Moon, A. R. 2014. A study of the native cell wall structures of the marine alga Ventricaria ventricosa (Siphonocladales, Chlorophyceae) using atomic force microscopy. Microscopy. DOI: 10.1093/jmicro/dft083

Preston, R. D.; Astbury, W. T. 1937. The structure of the wall of the green alga Valonia ventricosaProceedings of the Royal Society of London, Series B, Biological Sciences122(826): 76-97.

Wikipedia. Valonia ventricosa. Availabe at: < https://en.wikipedia.org/wiki/Valonia_ventricosa >. Access on April 6, 2016.

 

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Friday Fellow: Toxic gambierdisc

by Piter Kehoma Boll

Last week I introduced a coral reef fish, the porkfish, and mentioned that sometimes eating it may lead to ciguatera, a kind of food poisoning. So today I decided to introduce one of the main responsibles for ciguatera, the dinoflagellate Gambierdiscus toxicus, or toxic gambierdisc.

Light microscopy image of Gambierdiscus toxicus. Credits to David Patterson and Bob Andersen.*

Light microscopy image of Gambierdiscus toxicus. Credits to David Patterson and Bob Andersen.*

Gambierdiscus toxicus was discovered in 1975 in material collected around the Gambier Islands, where ciguatera often occurs, and described in 1979. As most dinoflagellates, it is unicellular and covered with hardened plates forming a structure called theca.

Living on the surface of seaweeds, especially brown algae, the toxic gambierdisc is ingested by fish who feed on the algae. Its toxins may therefore bioaccumulate in the fish’s tissues and be transfered to larger fish that feed on the smaller ones. If those fish are eaten by humans, it leads to ciguatera.

The symptoms of ciguatera poisoning include nausea, vomiting, diarrhea, headeaches, muscle aches, numbness, vertigo, hallucinations, etc. They may last from weeks to several years, sometimes up to two decades.

Among the main toxins produced by Gambierdiscus toxicus are ciguatoxins an maitotoxin. Ciguatoxins are lipophilic polyethers that act by lowering the threshold for opening sodium channels in synapses of the nervous system, which causes depolarization, leading to paralysis. On the other hand, maitotoxin is a hydrophilic molecule that activates extracellular calcium channels and may cause cell lysis and subsequent necrosis. There is no known antidote or effective treatment against ciguatera.

So, our lesson is: don’t mess with dinoflagellates!

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References:

Adachi, R.; Fukuyo, Y. 1979. The thecal structure of a marine toxic dinoflagellate Gambierdiscus toxicus gen. et sp. nov. collected in a ciguatera-endemic area. Bulletin of the Japanese Society of Scientific Fisheries, 45(1): 67-71.

Bagnis, R.; Chanteau, S.; Chungue, E.; Hurtel, J. M.; Yasumoto, T.; Inoue, A. 1980. Origins of ciguatera fish poisoning: a new dinoflagellate, Gambierdiscus toxicus Adachi and Fukuyo, definetely involved as a causal agent. Toxicon, 18: 199-209.

Wikipedia. Ciguatera. Availabe at: <https://en.wikipedia.org/wiki/Ciguatera >. Access on February 29, 2016.

Wikipedia. Ciguatoxin. Available at: <https://en.wikipedia.org/wiki/Ciguatoxin&gt;. Access on February 29, 2016.

Wikipedia. Maitotoxin. Available at: <https://en.wikipedia.org/wiki/Maitotoxin >. Access on February 29, 2016.

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