Pyrodinium
| Pyrodinium | |
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| Scientific classification | |
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| Species: | P. bahamense
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| Binomial name | |
| Pyrodinium bahamense Plate
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Introduction
Pyrodinium was first discovered in 1906 in the waters around New Providence Island in the Bahamas. Pyrodinium is a monospecific species with two varieties, Pyrodinium bahamense var. compressum and Pyrodinium bahamanse var. bahamense.
Habitat and Ecology
Pyrodinium bahamense, considered the sister taxon to Alexandrium, is a tropical photosynthetic euryhaline species of dinoflagellates found mainly in the Atlantic ocean.[1] It is found in marine waters that have more than 20 psu of salinity and are warmer than 22 °C (72 °F). The optimal salinity is considered to be around 35 psu[2] and the optimum temperature is 28 °C (82 °F).[1] An association between Pyrodinium bahamense occurrence and mangrove forests has been suggested, although, the presence of mangrove forest is not necessarily a predictor for presence of P. bahamense var. bahamense, as it is absent in western and southern Florida Bay.[3] P. bahamense has only been studied closely since the 1990s, since it was not cultured in labs before then. Several labs can now grow Pyrodinium in several common seawater based culture media such as ES-DK and f/2, but cell densities typically remain less than 10,000 cells mL−1 in culture and are lower than those normally obtained for Alexandrium.[1] The difficulty of culturing P. bahamense is explained by its specific nutrition needs. It shows optimal growth and chlorophyll levels when nitrogen levels in its environment are greater than 100 μM. It is believed that nitrogen is an important part of the synthesis of toxins in P. bahamense. P. bahamense displays bioluminescence when agitated, glowing blue.
Harmful Algal Blooms
Pyrodinium have caused caused more human illnesses and fatalities than any other dinoflagellates that cause Paralytic Shellfish Toxin or PST.[4] Although it was widely believed that the compressum variety is toxic and found in the Pacific while the bahamense variety is nontoxic and found in the Atlantic, a 1972 toxic algal bloom of Pyrodinium bahamense in Papua New Guinea [5] showed that P. bahamense could also be toxic. It is known now that P. bahamense is a major cause of seafood toxicity and cause of paralytic shellfish poisoning, especially in Southeast Asia. The species is also the cause of toxicity in Central American coasts.[6] It has also been discovered that there are at least two places in the world where both varieties of Pyrodium bahamense are found together, the Persian Gulf[7] and coast of Mexico.[6]
Bioluminescence
Pyrodinium bahamense is primarily responsible for the bioluminescence in the bioluminescent bays, or "bio bays," of Puerto Rico and the Bahamas.[8] The cobalt blue light produced by these dinoflagellates when they are mechanically disturbed creates a magical effect that draws many tourists to the bays. Most of the bays are in reserves, and no swimming is allowed, but guests are able to kayak in the bays at night with local guides to observe the bioluminescence.
Morphology/Anatomy
Pyrodinium bahamense cells are shaped like ellipsoids and are covered with thick thecal plates that have many small, evenly distributed knobs and trichocyst pores. They have an ornamental apical projection or node, as well as sulcal fins on either sides of the sulcus.[1]
The Pyrodinium resting cyst is spherical with many thin, tubular processes of variable length.[1]
Life cycle
In its dormant stages, P. bahamense develop spherical, double-layered cysts for protection. These cysts, called Polysphaeridium zoharyi in the paleontological classification system, are similar in both varieties and have tubular processes protruding from the outer layer.[1]
References
- ^ a b c d e f Usup, G., Ahmad, A., Matsuoka, K., Lim, P.T., Leaw ,C.P., 2012. Biology, ecology and bloom dynamics of the toxic marine dinoflagellate Pyrodinium bahamense. Harmful algae 14, 301-312.
- ^ Wall and Dale, "THE HYSTRICHOSPHAERID RESTING SPORE OF THE DINOFLAGELLATE PYRODINIUM BAHAMENSE", 1969
- ^ Phlips, E.J., Badylak, S., Bledsoe E.L., Cichra, M., 2006. Factors influencing the distribution and abundance of Pyrodinium bahamense in coastal ecosystems of Florida. Marine Ecology Progress Series 322, 99-115.
- ^ Usup, Gires (2012). "Biology, ecology and bloom dynamics of the toxic marine dinoflagellate Pyrodinium bahamense". Harmful Algae.
{{cite journal}}: line feed character in|title=at position 71 (help) - ^ McLean, Dewey M., "Eocladopyxis peniculatum Morgenroth, 1966, Early Tertiary Ancestor of the Modern Dinoflagellate Pyrodinium bahamense Plate, 1906", "Micropaleontology", 1976
- ^ a b Gárate-Lizárraga, Ismael et al., "Occurrence of Pyrodinium bahamense var. compressum along the southern coast of the Baja California Peninsula", "Marine Pollution Bulletin," 2011
- ^ Gilbert et al., "A fish kill of massive proportion in Kuwait Bay, Arabian Gulf", "Harmful Algae", 2002
- ^ Soler-Figueroa, Brenda María; Otero, Ernesto (2015-01-01). "The Influence of Rain Regimes and Nutrient Loading on the Abundance of Two Dinoflagellate Species in a Tropical Bioluminescent Bay, Bahía Fosforescente, La Parguera, Puerto Rico". Estuaries and Coasts. 38 (1): 84–92. doi:10.1007/s12237-014-9827-0. ISSN 1559-2731.