Lagerheimia | |
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Scientific classification ![]() | |
Kingdom: | Plantae |
Division: | Chlorophyta |
Class: | Trebouxiophyceae |
Order: | Chlorellales |
Family: | Oocystaceae |
Genus: | Lagerheimia Chodat |
Type species | |
Lagerheimia genevensis Chodat [1] | |
Species | |
Lagerheimia is a genus of green algae in the family Oocystaceae. [2] It is commonly found in freshwater habitats all over the world, [3] although some species are rare and have only been recorded from Europe or the United States. [4]
The genus name of Lagerheimia is in honour of Nils Gustaf Lagerheim (1860–1926), who was a Swedish botanist, mycologist, phycologist, and pteridologist. [5]
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. [4]
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. [4] 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. [4] [6] The genus is similar to Franceia , which has spines distributed all over the cell surface. [4] It may also be confused with single-celled forms of Desmodesmus , a genus that usually has coenobia of four or eight cells. [7]
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. [4]
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. [4]
Because Lagerheimia appears similar to one-celled forms of Desmodesmus, some authors have doubted the validity of this genus. [3] However, Lagerheimia strains are phylogenetically placed within the class Trebouxiophyceae. [8] In its current circumscription, Lagerheimia is polyphyletic: some species are more closely related to Franceia than to other Lagerheimia species. [8]