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Chaetoceros Diadema
''Chaetoceros diadema'' is a diatom in the genus'' Chaetoceros''. The easiest way to identify this species is by finding the very characteristic diadem-like resting spores. Species description Cells united into chains. Very characteristic, diadem - like spores (see species image). One chloroplast. Base of setae is short.Tomas, C. R., Hasle G. R., Syvertsen, E. E., Steidinger, K. A., Tangen, K., Throndsen, J., Heimdal, B. R., (1997). ''Identifying Marine Phytoplankton'', Academic Press. Similar species ''Chaetoceros constrictus ''Chaetoceros'' is probably the largest genus of marine planktonic diatoms with approximately 400 species described, although many of these descriptions are no longer valid. It is often very difficult to distinguish between different ''Chaeto ...'' is quite similar in the vegetative stage, but its resting spores are different from '' C. diadema'' resting spores . References Further reading External linksAlgaebase [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diatom
A diatom (Neo-Latin ''diatoma''), "a cutting through, a severance", from el, διάτομος, diátomos, "cut in half, divided equally" from el, διατέμνω, diatémno, "to cut in twain". is any member of a large group comprising several genera of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of the Earth's biomass: they generate about 20 to 50 percent of the oxygen produced on the planet each year, take in over 6.7 billion metric tons of silicon each year from the waters in which they live, and constitute nearly half of the organic material found in the oceans. The shells of dead diatoms can reach as much as a half-mile (800 m) deep on the ocean floor, and the entire Amazon basin is fertilized annually by 27 million tons of diatom shell dust transported by transatlantic winds from the African Sahara, much of it from the Bodélé Depression, which was once made up of a system of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaetoceros
''Chaetoceros'' is probably the largest genus of marine planktonic diatoms with approximately 400 species described, although many of these descriptions are no longer valid. It is often very difficult to distinguish between different ''Chaetoceros'' species. Several attempts have been made to restructure this large genus into subgenera and this work is still in progress.Tomas, C. R., Hasle G. R., Syvertsen, E. E., Steidinger, K. A., Tangen, K., Throndsen, J., Heimdal, B. R., (1997). ''Identifying Marine Phytoplankton'', Academic Press.Rines J. E. B., Theriot E. C., (2003). ''Systematics of Chaetocerotaceae (Bacillariophyceae). I. A phylogenetic analysis of the family'', Phycological research 51: 83–98. However, most of the effort to describe species has been focused in boreal areas, and the genus is cosmopolitan, so there are probably many tropical species still undescribed.J.E.B. Rines, P. Boonruang and E.C. Theriot., (2000).'' Chaetoceros phuketensis sp. nov. (Bacillario ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resting Spores
A resting spore is a resistant cell, used to survive adverse environmental conditions. Resting spore is a term commonly applied to both diatoms and fungi. In fungi A resting spore can be a spore created by fungi which is thickly encysted (has a thick cell wall) in order to survive through stressful times, such as drought. It protects the spore from biotic (microbial, fungal viral), as well as abiotic (wind, heat, xeric conditions) factors. Resting spores of a particular fungus are known create the phenomenon known as late potato blight. They can lie dormant within the soil of a field for decades until the right conditions occur for viability (plant host present, rain, fire etc.). In diatoms A similar resting spore life stage is also present in diatoms, and in such case, is also often referred to as the hypnospore. Importantly, the resting spore of marine diatoms is not an obligate stage of the life cycle, except in the minority of studied taxa, where spore production immedia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaetoceros Constrictus
''Chaetoceros'' is probably the largest genus of marine planktonic diatoms with approximately 400 species described, although many of these descriptions are no longer valid. It is often very difficult to distinguish between different ''Chaetoceros'' species. Several attempts have been made to restructure this large genus into subgenera and this work is still in progress.Tomas, C. R., Hasle G. R., Syvertsen, E. E., Steidinger, K. A., Tangen, K., Throndsen, J., Heimdal, B. R., (1997). ''Identifying Marine Phytoplankton'', Academic Press.Rines J. E. B., Theriot E. C., (2003). ''Systematics of Chaetocerotaceae (Bacillariophyceae). I. A phylogenetic analysis of the family'', Phycological research 51: 83–98. However, most of the effort to describe species has been focused in boreal areas, and the genus is cosmopolitan, so there are probably many tropical species still undescribed.J.E.B. Rines, P. Boonruang and E.C. Theriot., (2000).'' Chaetoceros phuketensis sp. nov. (Bacillariop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coscinodiscophyceae
The Coscinodiscophyceae are a class of diatoms. They are similar to the Centrales, a traditional, paraphyletic subdivision of the heterokont algae known as diatoms. The order is named for the shape of the cell walls (or valves or frustules) of centric diatoms, which are circular or ellipsoid in valve view. The valves often bear radially symmetrical ornamental patterns that can appear as dots when viewed with an optical microscope. Some also bear spines on their valves, which may either increase cell surface area and reduce sinking, or act as a deterrent to zooplankton grazers. Unlike pennate diatoms, centric diatoms never have a raphe. In terms of cell cycle, vegetative cells are diploid and undergo mitosis during normal cell division. In sexual species, oogamous meiosis produces haploid gametes, either ova or sperm cells. These fuse to produce a zygote which expands in size to develop into an auxospore from which full-sized vegetative cells are produced. In some taxonom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
