Lemmermannia | |
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Scientific classification | |
(unranked): | Viridiplantae |
Division: | Chlorophyta |
Class: | Trebouxiophyceae |
Order: | incertae sedis |
Family: | incertae sedis |
Genus: |
Lemmermannia Chodat, 1900 |
Species | |
Lemmermannia /ˌlɛməɹˈmæniə/ is a genus of fresh water trebouxiophyceans. as of March 2022 [update], the genus contains five described species. [1] They form coenobia of 4 to 16 cells. [2] Its type species is L. tetrapedia (Kirchner) Lemmermann, originally described in 1880 but put into the genus Lemmermannia in 1904. [2] [3] [4]
The genus is named in honor of German botanist Ernst Johann Lemmermann. [5]
In 1880, Kirchner described Staurogenia tetrapedia. [3]
In 1897, Schröder described Tetrapedia emarginata [6]
In 1898, Kuntze moved Staurogenia tetrapedia to the genus Crucigenia, in the name Crucigenia tetrapedia. [7]
In 1900, Chodat described the genus Lemmermannia and used T. emarginata (now L. emarginata) as the type of the new genus. [5]
In 1904, Lemmermann moved Crucigenia tetrapedia into Lemmermannia as Lemmermannia tetrapedia, which was not widely recognized; the old name Crucigenia tetrapedia was kept in use. [2] [4] The genus Lemmermannia had been ignored for many years until 2013. [2]
In 2013, Bock et al. found a new clade of algae including Crucigenia tetrapedia and three others using molecular methods. [2] Bock et al. (2013) decided that Crucigenia tetrapedia and Lemmermannia emarginata are the same organism. [2] Since C. tetrapedia was described first (in 1880) and has priority, it is the species name that should be used. [2] [3] The type of Lemmermannia thus changed its name, from L. emarginata to L. tetrapedia (Kirchner) Lemmermann 1904. [2] Three other species formerly in the genus Tetrastrum were added to Lemmermannia. [2]
Lemmermannia includes triangular or oval green, planktonic algae that mostly form tightly joined square coenobia of 4 cells, with or without small rectangular opening in the centre. [2] L. komarekii make coenobia of up to 16 cells in the form of near-square synceonobia, where 4 tetrads join together. [2] The cells have a single plastid, with or without a small pyrenoid. [2] All species lack spines, and mostly have smooth cell walls, with or without convexity. [2] A minority of L. punctata individuals, as well as old empty cells of the species, have granules on the outer cell walls. [2]
Lemmermannia tetrapedia can use hypoxanthine and allantoin as the only nitrogen source for photosynthesis, which indicates that eukaryotic algae share similar purine degradation pathway to higher plants, animals, and fungi. [8]
Lemmermannia perform asexual reproduction (autosporation by sporangium); sexual reproduction has not been observed. [2]
Lemmermannia species perform two types of reproduction: L. tetrapedia exhibits Crucigenia-type of autosporation where the daughter coenobium rotates 45˚ relative to the cell wall of the mother coenobium; the other four species produce daughter coenobia in the same orientation as the mother coenobia. [2] This demonstrates that in this taxon a Crucigenia-type of autosporation should not be used as a generic character.
Molecular phylogenies based on the SSU rDNA and ITS rRNA genes show Lemmermannia to be a sister clade to Botryococcus in Trebouxiophyceae. [2]
As of March 2022 [update], AlgaeBase accepted five species: [1]
All species inhabit freshwater around the globe. [2]
L. tetrapedia has been reported highly susceptible to heavy metals in water. [9]