Lagerheimia | |
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Scientific classification | |
(unranked): | Viridiplantae |
Division: | Chlorophyta |
Class: | Trebouxiophyceae |
Order: | Chlorellales |
Family: | Oocystaceae |
Genus: | Lagerheimia Chodat |
Species | |
Lagerheimia is a genus of green algae in the family Oocystaceae. [1] It is commonly found in freshwater habitats all over the world, [2] although some species are rare and have only been recorded from Europe or the United States. [3]
The genus name of Lagerheimia is in honour of Nils Gustaf Lagerheim (1860–1926), who was a Swedish botanist, mycologist, phycologist, and pteridologist. [4]
The genus was circumscribed by Giovanni Battista De Toni and Robert Hippolyte Chodat in Nuova Notarisia vol.6 on page 86-90 in 1895.
Lagerheimia consists of solitary cells. Cells are spherical, ellipsoidal, ovoid, polyhedral, or citriform (lemon-shaped), with one to several spines at the poles; some species also have spines at the equators. A layer of mucilage around the cell may be present. Cells contain a parietal chloroplast with one pyrenoid. [3]
Species identification is based on the shape of the cells, placement and length of the spines, and presence or absence of tubercles at the base of the spines. [3] Species with tubercles at the base of their spines have been classified in a separate genus, called Chodatella; however, modern authors do not recognize this split. [3] [5] The genus is similar to Franceia , which has spines distributed all over the cell surface. [3] It may also be confused with single-celled forms of Desmodesmus , a genus that usually has coenobia of four or eight cells. [6]
Lagerheimia reproduces asexually by zoospores or autospores. Zoospores have two flagella. When reproducing with autospores, 2, 4, or 8 are formed within the mother cell and are released when the mother cell wall ruptures. Reports of sexual reproduction have not been confirmed. [3]
Lagerheimia is placed in the family Oocystaceae . The cell wall ultrastructure of Lagerheimia subsalsa is similar to that of some species of Oocystis , and consists of several layers of microfibrils. Microfibrils are perpendicular from one layer to the next. [3]
Because Lagerheimia appears similar to one-celled forms of Desmodesmus, some authors have doubted the validity of this genus. [2] However, Lagerheimia strains are phylogenetically placed within the class Trebouxiophyceae. [7] In its current circumscription, Lagerheimia is polyphyletic: some species are more closely related to Franceia than to other Lagerheimia species. [7]
The Chlorophyceae are one of the classes of green algae, distinguished mainly on the basis of ultrastructural morphology. They are usually green due to the dominance of pigments chlorophyll a and chlorophyll b. The chloroplast may be discoid, plate-like, reticulate, cup-shaped, spiral- or ribbon-shaped in different species. Most of the members have one or more storage bodies called pyrenoids located in the chloroplast. Pyrenoids contain protein besides starch. Some green algae may store food in the form of oil droplets. They usually have a cell wall made up of an inner layer of cellulose and outer layer of pectose.
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.
Chlainomonas is a genus of algae in the family Chlamydomonadaceae. They are found in freshwater habitats or on snow, where they are one of the main algae responsible for causing watermelon snow.
Dictyochloris is a genus of green algae in the class Chlorophyceae. It is the sole genus of the family Dictyochloridaceae. It is commonly found in terrestrial and subaerial habitats.
Dictyochloropsis is a genus of unicellular green alga of the phylum Chlorophyta. This genus consists of free-living algae which have a reticulate (net-like) chloroplast that varies slightly in morphology between species, and that when mature always lacks a pyrenoid. Dictyochloropsis is asexual and reproduces using autospores.
Dictyosphaerium is a genus of green algae, in the family Chlorellaceae. It occurs in freshwater habitats around the world and is planktonic.
Dimorphococcus is a genus of fresh water green algae in the family Scenedesmaceae. It is found as a component of the phytoplankton of freshwater ponds, lakes, and peat bogs. It is widespread, but usually not very common.
Palmellopsis is a genus of green algae, specifically of the Palmellopsidaceae. They are either planktonic or attached to substrates in fresh water, or in aeroterrestrial habitats.
Paulschulzia is a genus of green algae, specifically of the family Tetrasporaceae.
Planktosphaeria is a genus of green algae, specifically of the Chlorophyceae. It was first described by the phycologist Gilbert Morgan Smith in 1918, with Planktosphaeria gelatinosa as its type species. Species of Planktosphaeria are commonly found in freshwater plankton around the world.
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.
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.
Sorastrum is a genus of green algae in the family Hydrodictyaceae. It is a component of the phytoplankton of freshwater ponds, lakes, and ditches. Sorastrum is common in tropical to temperate regions of the world, but due to its small size it is often overlooked.
Trebouxia is a unicellular green alga. It is a photosynthetic organism that can exist in almost all habitats found in polar, tropical, and temperate regions. It can either exist in a symbiotic relationship with fungi in the form of lichen or it can survive independently as a free-living organism alone or in colonies. Trebouxia is the most common photobiont in extant lichens. It is a primary producer of marine, freshwater and terrestrial ecosystems. It uses carotenoids and chlorophyll a and b to harvest energy from the sun and provide nutrients to various animals and insects.
Treubaria is a genus of green algae, the sole genus in the family Treubariaceae. Treubaria is found in freshwater habitats and has a cosmopolitan distribution.
Tetrastrum is a genus of green algae (Chlorophyta). It is a common component of the phytoplankton of freshwater habitats, particularly eutrophic and alkaline waters.
Bracteamorpha is a genus of green algae in the order Sphaeropleales, and is the only genus in the family Bracteamorphaceae. It contains a single species, Bracteamorpha trainorii.
Elongatocystis is an autotrophic green alga in the Oocystaceae family that is defined by its elongated type cell. This genus was discovered in a rockpool at Belvedere River, Mpumalanga, South Africa and described by Krienitz and Bock in 2011 along with two other strains of Oocystaceae. Its discovery and genetic analysis determined that Oocystis ecballocystiformis should be removed. In its place, the genus Elongatocystis was proposed to more accurately represent the phylogenetic tree.
Asterochloris is a genus of green algae in the family Trebouxiophyceae. It is a common photobiont in lichen, occurring in the thalli of more than 20 lichen genera worldwide. Asterochloris is distinguishable from the morphologically similar genus Trebouxia, primarily due to its deeply lobed chloroplast, the placement of the chloroplast along the cell's periphery before the initiation of zoospore or aplanospore formation, and its tendency to primarily reproduce asexually through the production of aplanospores.