Chlamydomonadales

Chlamydomonadales, also known as Volvocales, are an order of flagellated or pseudociliated green algae, specifically of the Chlorophyceae.

Very often they are taken to include the orders Volvocales and Dunallielales, which contain closely related unicellular flagellates, as suborders.

However, molecular phylogenetic studies have shown that the evolutionary relationships do not correspond to the traditional taxonomic classifications.

)[6] Phacotinia (Phacotus, Pteromonas)[6] Monadinia (Microglena)[7] Characiosiphonia (Characiosiphon, Lobocharacium) Arenicolinia (Chlorosarcinopsis arenicola) Stephanosphaerinia (Stephanosphaera) Chlorogonia (Chlorogonium) Polytominia (Polytoma uvella) Dunaliellinia (Dunaliella) Uncultured chlorophyte, Actinochloris sp.

Chloromonadinia (Chloromonas) Tatrensinia (Chlorococcum tatrense) Desmotetra Reinhardtinia (Chlamydomonas reinhardtii, Volvocaceae) Oogamochlamydinia (Oogamochlamys, Lobochlamys) Treubarinia (Treubaria, Trochiscia, Cylindrocapsa) Radicarteria (Carteria pro parte) Spermatozopsis similis Hafniomonas Crucicarteria (Carteria pro parte) Golenkinia

Schematic representation of the phylogenetic relationships of the volvocine algae and the parallel evolution of the spheroidal colony. Volvocine algae range from the unicellular Chlamydomonas to the multicellular Volvox through various intermediate forms and are used as a model for research into the evolution of multicellularity. The spheroidal colony is thought to have evolved twice independently within this group: once in the Volvocaceae, from Pandorina to Volvox, and the other in the genus Astrephomene. The phylogeny is based on previous reports. All drawings and photographs represent side views of individuals with anterior ends orienting toward the top of this figure. ^{[

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