Monactinus | |
---|---|
Monactinus simplex | |
Scientific classification | |
(unranked): | Viridiplantae |
Division: | Chlorophyta |
Class: | Chlorophyceae |
Order: | Sphaeropleales |
Family: | Hydrodictyaceae |
Genus: | Monactinus Corda, 1839 |
Species | |
Monactinus is a genus of green algae in the family Hydrodictyaceae. [1] It is very common in freshwater regions throughout the world. [2]
Monactinus forms flat colonies, termed coenobia, of cells in powers of two, usually four, eight, or 16. Coenobia are disc-shaped in outline, and marginal cells are drawn out into one lobe or point. This distinguishes it from Pediastrum and closely related genera, which have marginal cells which are drawn out into two lobes or points. [3] Monactinus shows a considerable amount of morphological diversity, with cells displaying different shapes, cell wall surface granulations, and inter-cellular gaps (or lack thereof). [4] Cells have one chloroplast filling the cell, each with a single pyrenoid. [3]
Although Monactinus was first described by August Carl Joseph Corda in 1839, for most of its history it was considered to be a synonym of Pediastrum . In 2005, molecular phylogenetic analyses showed that Pediastrum sensu lato was paraphyletic with respect to Hydrodictyon . Therefore, Pediastrum was split up into several genera, including Monactinus. [5]
Sphaeropleales is an order of green algae that used to be called Chlorococcales. The order includes some of the most common freshwater planktonic algae such as Scenedesmus and Pediastrum. The Spaeropleales includes vegetatively non-motile unicellular or colonial taxa that have biflagellate zoospores with flagella that are directly opposed in direction : Sphaeroplea, Atractomorpha, Neochloris, Hydrodictyon, and Pediastrum. All of these taxa have basal body core connections.
Gymnodinium is a genus of dinoflagellates, a type of marine and freshwater plankton. It is one of the few naked dinoflagellates, or species lacking armor known as cellulosic plates. Since 2000, the species which had been considered to be part of Gymnodinium have been divided into several genera, based on the nature of the apical groove and partial LSU rDNA sequence data. Amphidinium was redefined later. Gymnodinium belong to red dinoflagellates that, in concentration, can cause red tides. The red tides produced by some Gymnodinium, such as Gymnodinium catenatum, are toxic and pose risks to marine and human life, including paralytic shellfish poisoning.
Micrasterias is a unicellular green alga of the order Desmidiales. Its species vary in size reaching up to hundreds of microns.
Neochloridaceae is a family of green algae in the order Sphaeropleales.
Selenastraceae is a family of green algae in the order Sphaeropleales. Members of this family are common components of the phytoplankton in freshwater habitats worldwide. A few species have been found in brackish and marine habitats, such as in the Baltic Sea.
Eudorina is a paraphyletic genus in the volvocine green algae clade. Eudorina colonies consist of 16, 32 or 64 individual cells grouped together. Each individual cell contains flagella which allow the colony to move as a whole when the individual cells beat their flagella together. Description by GM Smith :
Ankistrodesmus is a genus of green algae in the family Selenastraceae. It is one of the most common types of phytoplankton in freshwater habitats around the world.
Lagerheimia is a genus of green algae in the family Oocystaceae. It is commonly found in freshwater habitats all over the world, although some species are rare and have only been recorded from Europe or the United States.
Parapediastrum is a genus of green algae in the family Hydrodictyaceae. It is fairly common in freshwater regions throughout the world.
Pediastrum is a genus of green algae, in the family Hydrodictyaceae. It is a photoautotrophic, nonmotile coenobial green alga that inhabits freshwater environments.
Pseudomuriella is a genus of green algae, specifically of the class Chlorophyceae. It is the sole genus of the family Pseudomuriellaceae. It is a terrestrial alga that inhabits soils.
Pseudopediastrum is a genus of green algae in the family Hydrodictyaceae. It is very common in freshwater regions throughout the world.
Raphidocelis is a genus of green algae in the family Selenastraceae. They are found in freshwater habitats.
Selenastrum is a genus of green algae in the family Selenastraceae. It is common in freshwater habitats around the world. Most species prefer temperate or warm-temperate waters.
Stauridium is a genus of green algae in the family Hydrodictyaceae. It is very common in freshwater regions throughout the world.
Pediastrum duplex is a species of fresh water green algae in the genus Pediastrum.
Phacus is a genus of unicellular excavates, of the phylum Euglenozoa, characterized by its flat, leaf-shaped structure, and rigid cytoskeleton known as a pellicle. These eukaryotes are mostly green in colour, and have a single flagellum that extends the length of their body. They are morphologically very flat, rigid, leaf-shaped, and contain many small discoid chloroplasts.
Sirogonium is a genus of filamentous charophyte green algae of the order Zygnematales. It is found in freshwater areas on all continents but Antarctica. Spirogyra measures approximately 32–115 μm in width. Each cell contains 2–10 chloroplasts in a ribbon, in contrast to the closely related genus Spirogyra, which has chloroplasts in a coil. Molecular phylogenetic studies have placed Sirogonium inside a clade consisting of Spirogyra species; in other words, Spirogyra is paraphyletic with respect to Sirogonium.
Chlorolobion, sometimes spelled Chlorolobium, is a genus of algae belonging to the family Selenastraceae. The species of this genus are found in freshwater habitats in Europe and America.
Prescottiella is a genus of green algae in the family Desmidiaceae, containing the single species Prescottiella sudanensis. Originally classified as Micrasterias sudanensis in 1958, it was moved into its own genus by Carlos E. M. Bicudo in 1976, due to its asymmetric character. It is named after Gerald Webber Prescott, an American phycologist.