The Klebsormidiaceae are a

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

containing five genera of

charophyte Charophyta () is a group of freshwater green algae, called charophytes (), sometimes treated as a division, yet also as a superdivision or an unranked clade. The terrestrial plants, the Embryophyta emerged within Charophyta, possibly from terre ...

green alga The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) have emerged deep in the Charophyte alga as ...

forming multicellular, non-branching filaments. The genus ''

Chlorokybus ''Chlorokybus'' is a multicellular (sarcinoid) genus of basal green algae or charophyte, a soil alga Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grou ...

'' was previously included as well, but this problematic and poorly known genus is now placed in a separate class Chlorokybophyceae. Klebsormidiaceae are the sister to the

Phragmoplastophyta The Phragmoplastophyta (Lecointre & Guyader 2006) are a proposed sister clade of the Klebsormidiaceae in the Streptophyte/Charophyte clade. The Phragmoplastophyta consist of the Charophycaea and another unnamed clade which contains the Coleochae ...

. Their ancestor was probably a

multicellular A multicellular organism is an organism that consists of more than one cell, in contrast to unicellular organism. All species of animals, land plants and most fungi are multicellular, as are many algae, whereas a few organisms are partially ...

freshwater green algae, and multicellularity will be retained in all of its descendants except the

Zygnematophyceae Zygnematophyceae (or Conjugatophyceae) is a class of green algae in the paraphylum streptophyte algae, also referred to as Charophyta, consisting of more than 4000 described species. It contains five orders: the Spirogloeales, the Serritaeniales ...

, which reverted back to unicellularity. Together with the unicellular Chlorokybophytina (

Mesostigmatophyceae The Mesostigmatophyceae are a class of basal green algae found in freshwater. In a narrow circumscription, the class contains a single genus, ''Mesostigma''. AlgaeBase then places the order within its circumscription of Charophyta. A clade co ...

, ''

Spirotaenia ''Spirotaenia'' is a genus of basal green algae that may be sister to the Chlorokybophyceae. It was previously considered to be part of the Zygnemataceae. It is sexually conjugating, a mode of reproduction that was previously only known in th ...

'' and

Chlorokybophyceae ''Chlorokybus'' is a multicellular (sarcinoid) genus of basal green algae or Charophyta, charophyte, a soil algae, alga. It has been classified as the sole member of the family Chlorokybaceae, which is the sole member of the order Chlorokybales, ...

), they comprise the

Streptophyta Streptophyta (), informally the streptophytes (, from the Greek ''strepto'' 'twisted', for the morphology of the sperm of some members), is a clade of plants. The composition of the clade varies considerably between authors, but the definition e ...

. The genera '' Koliella'' and '' Raphidonema'' were formerly classified as close relatives of ''Klebsormidium'', based on similarities in cell division. However, analysis of both nuclear and chloroplast DNA shows that both of these genera belong to the class

Trebouxiophyceae The Trebouxiophyceae are a class of green algae, in the division Chlorophyta. Their circumscription within the green algae is not well established due to the need for more genetic studies at higher levels within the group. Genera without interve ...

and are not charophytes. '' Interfilum'' (previously in

Ulotrichaceae Ulotrichaceae is a family of green algae The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) ...

) also emerged within this group.

References

External links

Charophyta Green algae families {{green alga-stub