Xanthidium | |
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Scientific classification | |
(unranked): | Viridiplantae |
(unranked): | Charophyta |
Class: | Zygnematophyceae |
Order: | Desmidiales |
Family: | Desmidiaceae |
Genus: | Xanthidium Ehrenberg ex Ralfs, 1848 |
Species [1] | |
Xanthidium is a genus of green algae, specifically of the Desmidiaceae. [2]
Xanthidium exists as symmetrical single cells. Cells are deeply constricted, forming two halves called semicells; they are rectangular, rounded, or polygonal in front view, flattened. The angles are usually drawn out into spines, which are typically paired and sometimes branched. Semicells often have a protuberance or additional spine in the center of the semicell. Cells have two or many axile chloroplasts which fill the cell. [3] [4] A notable exception is the species Xanthidium tumidum , formerly placed in the genus Staurastrum as Staurastrum tumidum. Morphologically it is triangular in cross section (unlike other species, which are flattened in cross section). Its placement in this genus is due to molecular data. [5]
Species identification of Xanthidium depends on the shape of the cell, cell wall ornamentation, and location and number of the spines. However, some species such as Xanthidium antilopaeum are notoriously polymorphic. [6]
Like other desmids, most species of Xanthidium prefer acidic waters. [7]
Euastrum oblongum is a species of desmid, in the family Desmidiaceae.
Carteria is a genus of green algae in the family Chlamydomonadaceae. Carteria are similar in morphology to the common genus Chlamydomonas and differ by having four, rather than two, flagella at the vegetative stage.
Quadrigula is a genus of green algae in the family Selenastraceae. It is commonly found in freshwater habitats as phytoplankton.
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.
The Desmidiaceae are one of four families of charophyte green algae in the order Desmidiales (desmids).
Bambusina is a genus of fresh-water green algae in the family Desmidiaceae.
Closterium is a genus of desmid, a group of charophyte green algae. It is placed in the family Closteriaceae. Species of Closterium are a common component of freshwater microalgae flora worldwide.
Cosmarium is a genus of freshwater organisms belonging to the Charophyta, a division of green algae from which the land plants (Embryophyta) emerged.
Desmidium is a genus of green algae, specifically of the Desmidiaceae.
Euastrum is a genus of green algae of the Desmidiaceae family. It lives in acidic waters.
Pleurotaenium is a genus of green algae, specifically of the desmids (Desmidiaceae).
Sphaerozosma is a genus of green algae, specifically of the Desmidiaceae.
Spinoclosterium is a genus of green algae, specifically of the Closteriaceae. It is rare, but widely distributed in freshwater regions throughout the world.
Staurastrum is a genus of green algae, specifically of the Desmidiaceae.
Staurodesmus is a genus of green algae, specifically of the Desmidiaceae.
Tetmemorus is a genus of green algae, specifically of the Desmidiaceae.
Triploceras is a genus of desmid in the family Desmidiaceae.
Mesostigma is a genus of unicellular biflagellate freshwater green algae, with a single species Mesostigma viride, covered by an outer layer of basket‐like scales instead of a cell wall. As of February 2022, AlgaeBase classified it as the only genus in the family Mesostigmataceae, the only family in the order Mesostigmatales, the only order in the class Mesostigmatophyceae. It is now considered to be one of the earliest diverging members of green plants/algae (Viridiplantae).
Cosmarium botrytis is a species of green algae in the family Desmidiaceae. It is a freshwater species with a worldwide distribution, and has been recorded from all continents.
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.