Search results
Results From The WOW.Com Content Network
The Chrysophyceae, usually called chrysophytes, chrysomonads, golden-brown algae or golden algae, are a large group of algae, found mostly in freshwater. [3] Golden algae is also commonly used to refer to a single species, Prymnesium parvum , which causes fish kills .
Diatoms belong to a large group called the heterokonts, which include both autotrophs such as golden algae and kelp; and heterotrophs such as water moulds. The classification of heterokonts is still unsettled: they may be designated a division , phylum , kingdom , or something intermediate to those.
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 fresh-water lakes.
The Coscinodiscophyceae are a class(s) of diatoms. [1] They are similar to the Centrales, a traditional, paraphyletic subdivision of the heterokont algae known as diatoms. [2] [3] [4] 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.
Chrysophyta or golden algae is a term used to refer to certain heterokonts. Dinobryon sp. from Shishitsuka Pond, Tsuchiura, Ibaraki Prefecture, Japan. It can be used to refer to: Chrysophyceae (golden algae), Bacillariophyceae (diatoms), and Xanthophyceae (yellow-green algae) together. [1] E.g., Pascher (1914). [2]
Diatoms are enclosed in protective silica (glass) shells called frustules. Each frustule is made from two interlocking parts covered with tiny holes through which the diatom exchanges nutrients and wastes. [156] The frustules of dead diatoms drift to the ocean floor where, over millions of years, they can build up as much as half a mile deep. [160]
As the diatom divides, each daughter retains one theca of the original frustule and produces one new theca. This means that one daughter cell is the same size as the parent (epitheca and new hypotheca) while in the other daughter the old hypotheca becomes the epitheca which together with a new and slightly smaller hypotheca comprises a smaller ...
Chaetoceros is a genus of diatoms in the family Chaetocerotaceae, first described by the German naturalist C. G. Ehrenberg in 1844. [1] Species of this genus are mostly found in marine habitats, but a few species exist in freshwater. [2] It is arguably the common and most diverse genus of marine planktonic diatoms, [3] with over 200 accepted ...