Editing Chlorophyta

{{About|a group of green algae|the genus with the common name 'spider plant'|Chlorophytum}}
{{Short description|Phylum of green algae}}
{{Automatic taxobox
| fossil_range = {{Long fossil range|1000|0|earliest=2040|ref={{Sfn|Tang|Pang|Yuan|Xiao|2020}}}}
| image = Haeckel Siphoneae.jpg
| image_caption = "Siphoneae" from [[Ernst Haeckel]]'s ''[[Kunstformen der Natur]]'', 1904
| display_parents = 5
| taxon = Chlorophyta
| authority = Reichenbach, 1828, emend. Pascher, 1914, emend. Lewis & McCourt, 2004{{Sfn|Reichenbach|1828|p=23}}{{Sfn|Pascher|1914}}{{Sfn|Adl|Bass|Lane|Lukeš|2019|p=36}}
| subdivision_ranks = Classes
| subdivision_ref = {{Sfn|Guiry|2024}}
| subdivision =
* [[Chloropicophyceae]]
* {{Extinct}}[[Chuariophyceae]]
* [[Mamiellophyceae]]
* [[Nephroselmidophyceae]]
* [[Picocystophyceae]]
* [[Pyramimonadophyceae]]
* [[Chlorophytina]]
** [[Chlorodendrophyceae]]
** [[Pedinophyceae]]
** [[Ulvophyceae]]
** [[Trebouxiophyceae]]
** [[Chlorophyceae]]
| synonyms =
* Chlorophycophyta {{Small|Papenfuss 1946}}{{Sfn|Papenfuss|1955}}
* Chlorophycota
* Chlorophytina
* Chlorophyllophyceae
* Isokontae
* Stephanokontae
| diversity = 7,934 species{{Br}} (6,851 living, 1,083 fossil){{Sfn|Guiry|2024|p=5}}
}}

'''Chlorophyta''' ({{Etymology|gre|chloros|yellow green||phyton|plant}}){{Sfn|Margulis|Chapman|2009|p=200}} is a [[division (botany)|division]] of [[green algae]] informally called '''chlorophytes'''.{{Sfn|Rockwell|Martin|Li|Mathews|2017}}

== Description ==

Chlorophytes are [[eukaryotic]] organisms composed of cells with a variety of coverings or walls, and usually a single green [[chloroplast]] in each cell.{{Sfn|Adl|Bass|Lane|Lukeš|2019|p=36}} They are structurally diverse: most groups of chlorophytes are [[unicellular]], such as the earliest-diverging [[prasinophyte]]s, but in two major classes ([[Chlorophyceae]] and [[Ulvophyceae]]) there is an evolutionary trend toward various types of complex [[colonial organism|colonies]] and even [[multicellularity]].{{Sfn|Margulis|Chapman|2009|p=200}}

{{Plain image with caption|image=Chlorophyte-cell-diagram.png|align=left|width=300px|caption-position=bottom|caption=Simplified diagram of a chlorophyte cell combining structures seen across the phylum: 1) [[flagellum]]; 2) synistosome with fibers adhering to a pair of basal bodies; 3) [[basal body]]; 4) microtubular rootlet belonging to the "X-2-X-2" arrangement, in this case 4-2-4-2 (only front-facing rootlets are shown); 5) flagellar pit (only two of four flagella are shown); 6) [[rhizoplast]]s; 7) [[Golgi apparatus]]; 8) [[endoplasmic reticulum]] and [[nuclear envelope]]; 9) [[eyespot apparatus]]; 10) [[cell nucleus|nucleus]] with [[nucleolus]]; 11) [[pyrenoid]]; 12) [[mitochondrion]]; 13) [[starch]] granule; 14) [[vacuole]]; 15) outer [[chloroplast]] membrane; 16) inner chloroplast membrane; 17) [[thylakoid]]; 18) [[cell membrane]].}}

=== Chloroplasts ===

Chlorophyte cells contain green chloroplasts surrounded by a double-membrane envelope. These contain [[chlorophyll]]s ''[[chlorophyll a|a]]'' and ''[[chlorophyll b|b]]'', and the [[carotenoid]]s [[carotin]], [[lutein]], [[zeaxanthin]], [[antheraxanthin]], [[violaxanthin]], and [[neoxanthin]], which are also present in the [[leaves]] of [[land plant]]s. Some special carotenoids are present in certain groups, or are synthesized under specific environmental factors, such as [[siphonaxanthin]], [[prasinoxanthin]], [[echinenon]], [[canthaxanthin]], [[loroxanthin]], and [[astaxanthin]]. They accumulate carotenoids under nitrogen deficiency, high irradiance of sunlight, or high salinity.{{Sfn|Solovchenko|Merzlyak|Khozin-Goldberg|Cohen|2010}}{{Sfn|Lee|2018|p=309}} In addition, they store [[starch]] inside the chloroplast as [[carbohydrate]] reserves.{{Sfn|Margulis|Chapman|2009|p=200}} The [[thylakoid]]s can appear single or in stacks.{{Sfn|Adl|Bass|Lane|Lukeš|2019|p=36}} In contrast to other divisions of algae such as [[Ochrophyta]], chlorophytes lack a chloroplast endoplasmic reticulum.{{Sfn|Lee|2018|p=310}}

=== Flagellar apparatus ===

Chlorophytes often form [[flagellate]] cells that generally have two or four [[flagella]] of equal length, although in prasinophytes heteromorphic (i.e. differently shaped) flagella are common because different stages of flagellar maturation are displayed in the same cell.{{Sfn|Graham|Graham|Wilcox|Cook|2022|pp=16-15}} Flagella have been independently lost in some groups, such as the [[Chlorococcales]].{{Sfn|Margulis|Chapman|2009|p=200}} Flagellate chlorophyte cells have symmetrical cross-shaped ('cruciate') root systems, in which [[ciliary rootlet]]s with a variable high number of [[microtubule]]s alternate with rootlets composed of just two microtubules; this forms an arrangement known as the "X-2-X-2" arrangement, unique to chlorophytes.{{Sfn|Lewis|McCourt|2004|p=1537}} They are also distinguished from [[streptophyte]]s by the place where their flagella are inserted: directly at the cell apex, whereas streptophyte flagella are inserted at the sides of the cell apex (sub-apically).{{Sfn|Graham|Graham|Wilcox|Cook|2022|pp=16–10}}

Below the flagellar apparatus of prasinophytes are [[rhizoplast]]s, contractile muscle-like structures that sometimes connect with the chloroplast or the cell membrane.{{Sfn|Graham|Graham|Wilcox|Cook|2022|pp=16–15}} In core chlorophytes, this structure connects directly with the surface of the nucleus.{{Sfn|Yamashita|Baluška|2023|p=2}}

The surface of flagella lacks microtubular hairs, but some genera present scales or fibrillar hairs.{{Sfn|Lee|2018|p=309}} The earliest-branching groups have flagella often covered in at least one layer of scales, if not naked.{{Sfn|Graham|Graham|Wilcox|Cook|2022|pp=16–15}}

=== Metabolism ===

Chlorophytes and streptophytes differ in the enzymes and organelles involved in [[photorespiration]]. Chlorophyte algae use a [[dehydrogenase]] inside the [[mitochondria]] to process [[glycolate]] during photorespiration. In contrast, streptophytes (including land plants) use [[peroxisome]]s that contain [[glycolate oxidase]], which converts glycolate to [[glycoxylate]], and the hydrogen peroxide created as a subproduct is reduced by [[catalase]]s located in the same organelles.{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=16-11}}

=== Reproduction and life cycle ===

[[Asexual reproduction]] is widely observed in chlorophytes. Among core chlorophytes, both unicellular groups can reproduce asexually through [[autospore]]s,{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=17-8}} wall-less zoospores,{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=17-11}} fragmentation, plain cell division, and exceptionally budding.{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=17-9}} Multicellular thalli can reproduce asexually through motile zoospores,{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=18-8}} non-motile [[aplanospore]]s, autospores, filament fragmentation,{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=19-3}} differentiated resting cells,{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=18-19}} and even unmated gametes.{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=18-29}} Colonial groups can reproduce asexually through the formation of autocolonies, where each cell divides to form a colony with the same number and arrangement of cells as the parent colony.{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=19-14}}

Many chlorophytes exclusively conduct asexual reproduction, but some display [[sexual reproduction]], which may be [[isogamy|isogamous]] (i.e., [[gamete]]s of both sexes are identical), [[anisogamy|anisogamous]] (gametes are different) or [[oogamy|oogamous]] (gametes are sperm and egg cells), with an evolutionary tendency towards oogamy. Their gametes are usually specialized cells differentiated from [[vegetative cell]]s, although in unicellular [[Volvocales]] the vegetative cells can function simultaneously as gametes. Most chlorophytes have a [[Biological_life_cycle#Diplontic_life_cycle|diplontic life cycle]] (also known as zygotic), where the gametes fuse into a [[zygote]] which germinates, grows and eventually undergoes [[meiosis]] to produce [[haploid]] [[spore]]s (gametes), similarly to [[ochrophyte]]s and [[animal]]s. Some exceptions display a [[Biological_life_cycle#Haplodiplontic_life_cycle|haplodiplontic life cycle]], where there is an alternation of generations, similarly to land plants.{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=16-13}} These generations can be isomorphic (i.e., of similar shape and size) or heteromorphic.{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=18-14}} The formation of reproductive cells usually does not occur in specialized cells,{{Sfn|Lee|2018|p=318}} but some [[Ulvophyceae]] have specialized reproductive structures: gametangia, to produce gametes, and sporangia, to produce spores.{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=18-14}}

The earliest-diverging unicellular chlorophytes (prasinophytes) produce walled resistant stages called [[microbial cyst|cysts]] or 'phycoma' stages before reproduction; in some groups the cysts are as large as 230 μm in diameter. To develop them, the flagellate cells form an inner wall by discharging mucilage vesicles to the outside, increase the level of lipids in the cytoplasm to enhance [[buoyancy]], and finally develop an outer wall. Inside the cysts, the nucleus and cytoplasm undergo [[cell division|division]] into numerous flagellate cells that are released by rupturing the wall. In some species these daughter cells have been confirmed to be gametes; otherwise, sexual reproduction is unknown in prasinophytes.{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=16-17}}

== Ecology ==

=== Free-living ===

[[Image:Taiwan 2009 East Coast ShihTiPing Giant Stone Steps Algae FRD 6581.jpg|thumb|Green algae on coastal rocks at [[:zh:石梯坪|Shihtiping]] in [[Taiwan]]]]
Chlorophytes are an important portion of the [[phytoplankton]] in both freshwater and marine habitats, [[carbon fixation|fixating]] more than a billion tons of carbon every year. They also live as multicellular [[macroalgae]], or [[seaweed]]s, settled along rocky ocean shores.{{Sfn|Margulis|Chapman|2009|p=200}} Most species of Chlorophyta are aquatic, prevalent in both marine and freshwater environments. About 90% of all known species live in freshwater.{{Sfn|Lee|2018}} Some species have adapted to a wide range of terrestrial environments. For example, ''[[Chlamydomonas nivalis]]'' lives on summer alpine snowfields, and ''[[Trentepohlia (alga)|Trentepohlia]]'' species, live attached to rocks or woody parts of trees.{{Sfn|Graham|Graham|Wilcox|Cook|2022}}{{Sfn|Leliaert|Smith|Moreau|Herron|2012}} Several species have adapted to specialised and extreme environments, such as deserts, arctic environments, [[hypersaline]] habitats, marine deep waters, deep-sea [[hydrothermal vent]]s and habitats that experience extreme changes in temperature, light and salinity.{{Sfn|Lewis|Lewis|2005}}{{Sfn|De Wever|Leliaert|Verleyen|Vanormelingen|2009}}{{Sfn|Leliaert|Verbruggen|Zechman|2011}} Some groups, such as the [[Trentepohliales]], are exclusively found on land.{{Sfn|López-Bautista|Rindi|Guiry|2006}}{{Sfn|Foflonker|Ananyev|Qiu|Morrison|2016}}

=== Symbionts ===

Several species of Chlorophyta live in [[symbiosis]] with a diverse range of [[eukaryote]]s, including [[fungi]] (to form [[lichen]]s), [[ciliate]]s, [[Foraminifera|forams]], [[cnidarian]]s and [[mollusc]]s.{{Sfn|Leliaert|Smith|Moreau|Herron|2012}} Some species of Chlorophyta are [[heterotrophic]], either free-living or [[parasitic]].{{Sfn|Joubert|Rijkenberg|1971}}{{Sfn|Nedelcu|2001}} Others are [[mixotroph]]ic [[bacterivore]]s through [[phagocytosis]].{{Sfn|Anderson|Charvet|Hansen|2018}} Two common species of the heterotrophic green alga ''[[Prototheca]]'' are [[pathogenic]] and can cause the disease [[protothecosis]] in humans and animals.{{Sfn|Tartar|Boucias|Adams|Becnel|2002}}

With the exception of the three classes [[Ulvophyceae]], [[Trebouxiophyceae]] and [[Chlorophyceae]] in the [[UTC clade]], which show various degrees of multicellularity, all the Chlorophyta lineages are unicellular.{{Sfn|Umen|2014}} Some members of the group form [[symbiosis|symbiotic]] relationships with [[protozoa]], sponges, and cnidarians. Others form symbiotic relationships with fungi to form [[lichen]]s, but the majority of species are free-living. All members of the clade have motile flagellated swimming cells.{{Sfn|Kapraun|2007}} ''[[Monostroma kuroshiense]]'', an edible green alga cultivated worldwide and most expensive among green algae, belongs to this group.

== Systematics ==

=== Taxonomic history ===

The first mention of Chlorophyta belongs to German botanist [[Heinrich Gottlieb Ludwig Reichenbach]] in his 1828 work ''Conspectus regni vegetabilis''. Under this name, he grouped all algae, [[mosses]] ('musci') and [[ferns]] ('filices'), as well as some [[seed plants]] (''[[Zamia]]'' and ''[[Cycas]]'').{{Sfn|Reichenbach|1828|p=23–40}} This usage did not gain popularity. In 1914, Bohemian botanist [[Adolf Pascher]] modified the name to encompass exclusively [[green algae]], that is, algae which contain [[chlorophyll]]s [[chlorophyll a|''a'']] and [[chlorophyll b|''b'']] and store [[starch]] in their [[chloroplast]]s.{{Sfn|van den Hoek|Mann|Jahns|1995}} Pascher established a scheme where Chlorophyta was composed of two groups: Chlorophyceae, which included algae now known as Chlorophyta, and [[Conjugatae]], which are now known as Zygnematales and belong to the [[Streptophyta]] clade from which land plants evolved.{{Sfn|Pascher|1914}}{{Sfn|Lewis|McCourt|2004}}

During the 20th century, many different classification schemes for the Chlorophyta arose. The [[Smith system]], published in 1938 by American botanist [[Gilbert Morgan Smith]], distinguished two classes: Chlorophyceae, which contained all green algae (unicellular and multicellular) that did not grow through an [[apical cell]]; and Charophyceae, which contained only multicellular green algae that grew via an apical cell and had special sterile envelopes to protect the sex organs.{{Sfn|Smith|1938|p=12}}

With the advent of [[electron microscopy]] studies, botanists published various classification proposals based on finer cellular structures and phenomena, such as [[mitosis]], [[cytokinesis]], [[cytoskeleton]], [[flagella]] and [[cell wall]] [[polysaccharides]].{{Sfn|Mattox|Stewart|1984}}{{Sfn|Lobban|Wynne|1981|p=88}} British botanist {{Ill|Frank Eric Round|nl}} proposed in 1971 a scheme which distinguishes Chlorophyta from other green algal divisions Charophyta, Prasinophyta and Euglenophyta. He included four classes of chlorophytes: [[Zygnemaphyceae]], Oedogoniophyceae, Chlorophyceae and Bryopsidophyceae.{{Sfn|Round|1971}} Other proposals retained the Chlorophyta as containing all green algae, and varied from one another in the number of classes. For example, the 1984 proposal by Mattox & Stewart included five classes,{{Sfn|Mattox|Stewart|1984}} while the 1985 proposal by Bold & Wynne included only two,{{Sfn|Bold|Wynne|1985}} and the [[Hoek, Mann and Jahns system|1995 proposal by Christiaan van den Hoek and coauthors]] included up to eleven classes.{{Sfn|van den Hoek|Mann|Jahns|1995}}

The modern usage of the name 'Chlorophyta' was established in 2004, when phycologists Lewis & McCourt firmly separated the chlorophytes from the streptophytes on the basis of [[molecular phylogenetics]]. All green algae that were more closely related to land plants than to chlorophytes were grouped as a [[paraphyletic]] [[division (botany)|division]] [[Charophyta]].{{Sfn|Lewis|McCourt|2004}}

Within the green algae, the earliest-branching lineages were grouped under the informal name of "[[prasinophyte]]s", and they were all believed to belong to the Chlorophyta clade.{{Sfn|Lewis|McCourt|2004}} However, in 2020 a study recovered a new clade and division known as [[Prasinodermophyta]], which contains two prasinophyte lineages previously considered chlorophytes.{{Sfn|Li|Wang|Wang|Sahu|2020}} Below is a cladogram representing the current state of green algal classification:{{Sfn|Lopes dos Santos|Pollina|Gourvil|Corre|2017}}{{Sfn|Li|Wang|Wang|Sahu|2020}}{{Sfn|Gulbrandsen|Andresen|Krabberød|Bråte|2021}}{{Sfn|Yang|Ma|Wang|Tian|2023}}

{{Clade|style=font-size:90%;line-height:50%;|label1=[[Viridiplantae]]|1={{Clade
 |1={{Clade|label1=[[Prasinodermophyta]]|barbegin1=blue|1={{Clade
  |1=[[Prasinodermophyceae]]
  |2=[[Palmophyllophyceae]]
}}}}
 |2={{Clade
  |label1='''Chlorophyta'''|1={{Clade
   |bar1=blue|1={{Clade
    |1=[[Pyramimonadophyceae]]
    |2=[[Mamiellophyceae]]
   }}
   |2={{Clade
    |bar1=blue|1=[[Nephroselmidophyceae]]
    |2={{Clade
     |bar1=blue|1=[[Pseudoscourfieldiales]]|state1=dashed
     |2={{Clade
      |bar1=blue|1=[[Picocystophyceae]]
      |2={{Clade
       |bar1=blue|1=[[Chloropicophyceae]]
       |2={{Clade|label1=[[Tetraphytina|core clade]]|1={{Clade
        |2=[[Pedinophyceae]]
        |1={{Clade
         |barend1=blue|1=[[Chlorodendrophyceae]]
         |2={{Clade|label1=[[UTC clade|UTC]]|1={{Clade
          |1=[[Trebouxiophyceae]]
          |2={{Clade
           |1=[[Chlorophyceae]]
           |2=[[Ulvophyceae]]}}
          }}
         }}
        }}
       }}
       }}
      }}
     }}
    }}
   }}
  }}
  |label2=[[Streptophyta]]|2={{Clade
   |barbegin1=green|1={{Clade
    |1=[[Mesostigmatophyceae]]
    |2=[[Chlorokybophyceae]]
   }}
   |2={{Clade
    |bar1=green|1=[[Klebsormidiophyceae]]
    |2={{Clade
     |bar1=green|1=[[Charophyceae]]
     |2={{Clade
      |bar1=green|1=[[Coleochaetophyceae]]
      |2={{Clade
       |barend1=green|1=[[Zygnematophyceae]]
       |2=[[Embryophyta]] (land plants)
      }}
     }}
    }}
   }}
  }}
 }}
}}
|grouplabel1={{Clade labels
 |label1="[[charophyte]]s"|top1=78%
 |label2="[[prasinophyte]]s"|top2=22%
}}
}}

=== Classification ===
{{Multiple image|perrow=2|total_width=330
| image1 = Tetraselmis suecica in a vegetative non-motile stage 01.jpg
| caption1 = ''Tetraselmis suecica'' (Chlorodendrophyceae)
| image2 = Volvox_aureus.jpg
| caption2 = ''Volvox aureus'' (Chlorophyceae)
| image3 = Chloropicon sieburthii LM A2.png
| caption3 = ''Chloropicon sieburthii'' (Chloropicophyceae)
| image4 = Deposition velocity versus cell diameters-6.jpg
| caption4 = ''Micromonas pusilla'' (Mamiellophyceae)
| image5 = Nephroselmis_olivacea,_Stein_(1878),_plate_19_cropped.jpg
| caption5 = ''Nephroselmis olivacea'' (Nephroselmidophyceae)
| image6 = Mantoniella tinhauana fmicb-15-1358574-g003.jpg
| caption6 = ''Mantoniella tinhauana'' (Pedinophyceae)
| image7 = Picocystis_salinarum.jpg
| caption7 = ''Picocystis salinarum'' (Picocystophyceae)
| image8 = Pyramimonas longicauda 1.jpg
| caption8 = ''Pyramimonas longicauda'' (Pyramimonadophyceae)
| image9 = Coccomyxa polymorpha.png
| caption9 = ''Coccomyxa polymorpha'' (Trebouxiophyceae)
| image10 = Sea_lettuce_in_Brofjorden_1_-_cropped.jpg
| caption10 = ''Ulva lactuca''{{Br}}(Ulvophyceae)
| header = {{Small|Representatives of all living classes of chlorophytes}}
}}
Currently eleven chlorophyte classes are accepted, here presented in alphabetical order with some of their characteristics and [[biodiversity]]:

* [[Chlorodendrophyceae]] (60 species, 15 extinct):{{Sfn|Guiry|2024|p=5}} unicellular [[flagellate]]s (monadoids) surrounded by an outer cell covering or [[theca]] of organic extracellular scales composed of [[protein]]s and ketosugars. Some of these scales make up hair-like structures. Capable of [[asexual reproduction]] through cell division inside the theca. No [[sexual reproduction]] has been described. Each cell contains a single chloroplast and exhibits two [[flagella]]. Present in marine and freshwater habitats.{{Sfn|Hori|Norris|Chihara|1986}}{{Sfn|Adl|Bass|Lane|Lukeš|2019|p=37}}{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=17-2}}

* [[Chlorophyceae]] (3,974 species):{{Sfn|Guiry|2024|p=5}} either unicellular monadoids (flagellated) or [[wikt:coccoid|coccoid]]s (without flagella) living solitary or in varied colonial forms (including [[coenocyte|coenobial]]), or [[multicellular]] filamentous (branch-like) [[thalli]] that may be ramified, or foliose (leaf-like) thalli. Cells are surrounded by a crystalline covering composed of [[glycoprotein]]s abundant in [[glycine]] and [[hydroxyproline]], as well as [[pectin]]s, [[arabinogalactan protein]]s, and [[extensin]]. They exhibit a [[Biological_life_cycle#Haplontic_life_cycle|haplontic life cycle]] with [[isogamy]], [[anisogamy]] or [[oogamy]]. They are capable of asexual reproduction through flagellated [[zoospore]]s, [[aplanospore]]s, or [[autospore]]s. Each cell contains a single chloroplast, a variable number of [[pyrenoid]]s (including lack thereof), and from one to hundreds of flagella without [[mastigoneme]]s. Present in marine, freshwater and terrestrial habitats.{{Sfn|Domozych|Ciancia|Fangel|Mikkelsen|2012}}{{Sfn|Leliaert|Smith|Moreau|Herron|2012}}{{Sfn|Adl|Bass|Lane|Lukeš|2019|p=36–37}}{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=19-2–19-5}}

* [[Chloropicophyceae]] (8 species):{{Sfn|Guiry|2024|p=5}} unicellular solitary coccoids. Cells are surrounded by a multi-layered [[cell wall]]. No sexual or asexual reproduction has been described. Each cell contains a single chloroplast with [[astaxanthin]] and [[loroxanthin]], and lacks pyrenoids or flagella. They are exclusively marine.{{Sfn|Lopes dos Santos|Pollina|Gourvil|Corre|2017}}

* [[Chuariophyceae]] (3 extinct species): exclusively fossil group containing carbonaceous megafossils found in [[Ediacaran]] rocks, such as ''[[Tawuia]]''.{{Sfn|Guiry|2024|p=5}}{{Sfn|Srivastava|2002}}

* [[Mamiellophyceae]] (25 species):{{Sfn|Guiry|2024|p=5}} unicellular solitary monadoids. Cells are naked or covered by one or two layers of flat scales, mainly with spiderweb-like or reticulate ornamentation. Each cell contains one or rarely two chloroplasts, almost always with [[prasinoxanthin]]; two equal or unequal flagella, or just one flagellum, or lacking any flagella. If flagella are present, they can be either smooth or covered in scales in the same manner as the cells. Present in marine and freshwater habitats.{{Sfn|Marin|Melkonian|2010}}{{Sfn|Adl|Bass|Lane|Lukeš|2019|p=37}}

* [[Nephroselmidophyceae]] (29 species):{{Sfn|Guiry|2024|p=5}} unicellular monadoids. Cells are covered by scales. They are capable of sexual reproduction through [[hologamy]] (fusion of entire cells), and of asexual reproduction through [[binary fission]]. Each cell contains a single cloroplast, a pyrenoid, and two flagella covered by scales. Present in marine and freshwater habitats.{{Sfn|Nakayama|Suda|Kawachi|Inouye|2007}}{{Sfn|Yamaguchi|Suda|Nakayama|Pienaar|2010}}{{Sfn|Adl|Bass|Lane|Lukeš|2019|p=37}}

* [[Pedinophyceae]] (24 species):{{Sfn|Guiry|2024|p=5}} unicellular asymmetrical monadoids that undergo a coccoid palmelloid phase covered by [[mucilage]]. Cells lack extracellular scales, but in rare cases are covered on the posterior side by a theca. Each cell contains a single chloroplast, a pyrenoid, and a single flagellum usually covered in mastigonemes. Present in marine, freshwater and terrestrial habitats.{{Sfn|Marin|2012}}{{Sfn|Adl|Bass|Lane|Lukeš|2019|p=37}}{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=17-3}}

* [[Picocystophyceae]] (1 species):{{Sfn|Guiry|2024|p=5}} unicellular coccoids, ovoid and trilobed in shape. Cells are surrounded by a multi-layered cell wall of poly-[[arabinose]], [[mannose]], [[galactose]] and [[glucose]]. No sexual reproduction has been described. They are capable of asexual reproduction through autosporulation, resulting in two or rarely four daughter cells. Each cell contains a single bilobed chloroplast with diatoxanthin and monadoxanthin, without any pyrenoid or flagella. Present in [[saline lake]]s.{{Sfn|Lewin|Krienitz|Goericke|Takeda|2000}}{{Sfn|Lopes dos Santos|Pollina|Gourvil|Corre|2017}}{{Sfn|Adl|Bass|Lane|Lukeš|2019|p=37}}

* [[Pyramimonadophyceae]] (166 species, 59 extinct):{{Sfn|Guiry|2024|p=5}} unicellular monadoids or coccoids. Cells are covered by two or more layers of organic scales. No sexual reproduction has been described, but some cells with only one flagellum have been interpreted as potential gametes. Asexual reproduction has only been observed in the coccoid forms, via zoospores. Each cell contains a single chloroplast, a pyrenoid, and between 4 and 16 flagella. The flagella are covered in at least two layers of organic scales: a bottom layer of pentagonal scales organized in 24 rows, and a top layer of limuloid scales distributed in 11 rows. They are exclusively marine.{{Sfn|Adl|Bass|Lane|Lukeš|2019|p=37}}{{Sfn|Daugbjerg|Fassel|Moestrup|2020}}

* [[Trebouxiophyceae]] (926 species, 1 extinct):{{Sfn|Guiry|2024|p=5}} unicellular monadoids occasionally without flagella, or colonial, or ramified filamentous thalli, or living as the [[photobiont]]s of [[lichen]]. Cells are covered by a cell wall of [[cellulose]], [[algaenan]]s, and β-galactofuranane. No sexual reproduction has been described with the exception of some observations of gamete fusion and presence of [[meiosis|meiotic]] [[gene]]s. They are capable of asexual reproduction through autospores or zoospores. Each cell contains a single chloroplast, a pyrenoid, and one or two pairs of smooth flagella. They are present in marine, freshwater and terrestrial habitats.{{Sfn|Domozych|Ciancia|Fangel|Mikkelsen|2012}}{{Sfn|Fučíková|Pažoutová|Rindi|2015}}{{Sfn|Adl|Bass|Lane|Lukeš|2019|p=36}}{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=17-4–17-11}}

* [[Ulvophyceae]] (2,695 species, 990 extinct):{{Sfn|Guiry|2024|p=5}} macroscopic thalli, either filamentous (which may be ramified) or foliose (composed of monostromatic or distromatic layers) or even compact tubular forms, generally [[multinucleate]]. Cells surrounded by a cell wall that may be [[Marine biogenic calcification|calcified]], composed of cellulose, β-manane, β-xilane, sulphated or piruvilated polysaccharides or sulphated ramnogalacturonanes, arabinogalactan proteins, and extensin. They exhibit a [[Biological_life_cycle#Haplodiplontic_life_cycle|haplodiplontic life cycle]] where the alternating generations can be isomorphic or heteromorphic. They reproduce asexually via zoospores that may be covered in scales. Each cell contains a single chloroplast, and one or two pairs of flagella without mastigonemes but covered in scales. They are present in marine, freshwater and terrestrial habitats.{{Sfn|Domozych|Ciancia|Fangel|Mikkelsen|2012}}{{Sfn|Adl|Bass|Lane|Lukeš|2019|p=36}}{{Sfn|Graham|Graham|Wilcox|Cook|2022|p=18-2–18-24}}

== Evolution ==

In February 2020, the fossilized remains of a green alga, named ''[[Proterocladus antiquus]]'' were discovered in the northern province of [[Liaoning]], [[China]]. At around a billion years old, it is believed to be one of the oldest examples of a multicellular chlorophyte. It is currently classified as a member of order [[Cladophorales|Siphonocladales]], class [[Ulvophyceae]].{{Sfn|Tang|Pang|Yuan|Xiao|2020}} In 2023, a study calculated the [[molecular clock|molecular age]] of green algae as [[Molecular_clock#Calibration|calibrated]] by this fossil. The study estimated the origin of Chlorophyta within the [[Mesoproterozoic]] era, at around 2.04–1.23 billion years ago.{{Sfn|Yang|Ma|Wang|Tian|2023}}

== Usage ==

=== Model organisms ===

Among chlorophytes, a small group known as the volvocine green algae is being researched to understand the origins of [[cell differentiation]] and [[multicellularity]]. In particular, the unicellular flagellate ''[[Chlamydomonas reinhardtii]]'' and the colonial organism ''[[Volvox carteri]]'' are object of interest due to sharing [[Homology (biology)|homologous]] [[genes]] that in ''Volvox'' are directly involved in the development of two different cell types with full division of labor between swimming and reproduction, whereas in ''Chlamydomonas'' only one cell type exists that can function as a [[gamete]]. Other volvocine species, with intermediate characters between these two, are studied to further understand the transition towards the cellular division of labor, namely ''[[Gonium pectorale]]'', ''[[Pandorina morum]]'', ''[[Eudorina elegans]]'' and ''[[Pleodorina starrii]]''.{{Sfn|Nishii|Miller|2010}}

=== Industrial uses ===

Chlorophyte [[microalgae]] are a valuable source of [[biofuel]] and various chemicals and products in industrial amounts, such as [[carotenoid]]s, [[vitamin]]s and [[unsaturated fatty acid]]s. The genus ''[[Botryococcus]]'' is an efficient producer of hydrocarbons, which are converted into [[biodiesel]]. Various genera (''[[Chlorella]]'', ''[[Scenedesmus]]'', ''[[Haematococcus]]'', ''[[Dunaliella]]'' and ''[[Tetraselmis]]'') are used as cellular factories of biomass, lipids and different vitamins for either human or animal consumption, and even for usage as pharmaceuticals. Some of their pigments are employed for cosmetics.{{Sfn|Baudelet|Ricochon|Linder|Muniglia|2017}}

==References==

=== Citations ===
{{Reflist|23em}}

=== Cited literature ===
{{Refbegin|23em|indent=yes}}
* {{Cite journal
 |last1=Adl |first1=Sina M.
 |last2=Bass |first2=David
 |last3=Lane |first3=Christopher E.
 |last4=Lukeš |first4=Julius
 |last5=Schoch |first5=Conrad L.
 |last6=Smirnov |first6=Alexey
 |last7=Agatha |first7=Sabine
 |last8=Berney |first8=Cedric
 |last9=Brown |first9=Matthew W.
 |last10=Burki |first10=Fabien
 |last11=Cárdenas |first11=Paco
 |last12=Čepička |first12=Ivan
 |last13=Chistyakova |first13=Lyudmila
 |last14=Del Campo |first14=Javier
 |last15=Dunthorn |first15=Micah
 |last16=Edvardsen |first16=Bente
 |last17=Eglit |first17=Yana
 |last18=Guillou |first18=Laure
 |last19=Hampl |first19=Vladimír
 |last20=Heiss |first20=Aaron A.
 |last21=Hoppenrath |first21=Mona
 |last22=James |first22=Timothy Y.
 |last23=Karnkowska |first23=Anna
 |last24=Karpov |first24=Sergey
 |last25=Kim |first25=Eunsoo
 |last26=Kolisko |first26=Martin
 |last27=Kudryavtsev |first27=Alexander
 |last28=Lahr |first28=Daniel J.G.
 |last29=Lara |first29=Enrique
 |last30=Le Gall |first30=Line
 |display-authors=10
 |date=2019
 |title=Revisions to the Classification, Nomenclature, and Diversity of Eukaryotes |url=https://doi.org/10.1111%2FJEU.12691 |journal=Journal of Eukaryotic Microbiology
 |volume=66 |issue=1 |pages=4–119 |doi=10.1111/JEU.12691 |pmc=6492006 |pmid=30257078}}
* {{Cite journal
 |last1=Anderson |first1=R.
 |last2=Charvet |first2=S.
 |last3=Hansen |first3=P. J.
 |date=2018
 |title=Mixotrophy in Chlorophytes and Haptophytes—Effect of Irradiance, Macronutrient, Micronutrient and Vitamin Limitation |journal=Frontiers in Microbiology
 |volume=9 |page=1704 |doi=10.3389/fmicb.2018.01704 |pmc=6080504 |pmid=30108563 |doi-access=free}}
* {{Cite journal
 |last1=Baudelet |first1=Paul-Hubert
 |last2=Ricochon |first2=Guillaume
 |last3=Linder |first3=Michel
 |last4=Muniglia |first4=Lionel
 |date=2017
 |title=A new insight into cell walls of Chlorophyta |journal=Algal Research
 |volume=25 |issue=1 |pages=333–371 |doi=10.1016/j.algal.2017.04.008|bibcode=2017AlgRe..25..333B
 }}
* {{Cite journal
 |last1=Becker |first1=Burkhard
 |last2=Marin |first2=Birger
 |date=2009
 |title=Streptophyte algae and the origin of embryophytes |journal=Annals of Botany
 |volume=103 |issue=7 |pages=999–1004 |doi=10.1093/aob/mcp044 |pmc=2707909 |pmid=19273476 |ref=none}}
* {{Cite book
 |last1=Bold |first1=Harold Charles
 |title=Introduction to the algae : structure and reproduction
 |last2=Wynne |first2=Michael James |publisher=Prentice-Hall
 |date=1985 |isbn=978-0-1347-7746-7 |edition=2nd |location=Englewood Cliffs, N.J.}}
* {{Cite journal
 |last1=Daugbjerg |first1=Niels
 |last2=Fassel |first2=Nicolai M. D.
 |last3=Moestrup |first3=Øjvind
 |date=2020
 |title=Microscopy and phylogeny of ''Pyramimonas tatianae'' sp. nov. (Pyramimonadales, Chlorophyta), a scaly quadriflagellate from Golden Horn Bay (eastern Russia) and formal description of Pyramimonadophyceae classis nova |journal=European Journal of Phycology
 |volume=55 |issue=1 |pages=49–63 |doi=10.1080/09670262.2019.1638524 |doi-access=free|bibcode=2020EJPhy..55...49D
 }}
* {{Cite journal
 |last1=De Wever |first1=Aaike
 |last2=Leliaert |first2=Frederik
 |last3=Verleyen |first3=Elie
 |last4=Vanormelingen |first4=Pieter
 |last5=Van der Gucht |first5=Katleen
 |last6=Hodgson |first6=Dominic A.
 |last7=Sabbe |first7=Koen
 |last8=Vyverman |first8=Wim
 |date=October 2009
 |title=Hidden levels of phylodiversity in Antarctic green algae: further evidence for the existence of glacial refugia |journal=Proceedings of the Royal Society B: Biological Sciences
 |volume=276 |issue=1673 |pages=3591–3599 |doi=10.1098/rspb.2009.0994 |pmc=2817313 |pmid=19625320}}
* {{Cite journal
 |last1=Domozych |first1=David S.
 |last2=Ciancia |first2=Marina
 |last3=Fangel |first3=Jonatan U.
 |last4=Mikkelsen |first4=Maria Dalgaard
 |last5=Ulvskov |first5=Peter
 |last6=Willats |first6=William G. T.
 |date=2012
 |title=The Cell Walls of Green Algae: A Journey through Evolution and Diversity |journal=Frontiers in Plant Science
 |volume=3 |pages=82 |doi=10.3389/fpls.2012.00082 |pmc=3355577 |pmid=22639667 |doi-access=free}}
* {{Cite journal
 |last1=Foflonker |first1=Fatima
 |last2=Ananyev |first2=Gennady
 |last3=Qiu |first3=Huan
 |last4=Morrison |first4=Andrenette
 |last5=Palenik |first5=Brian
 |last6=Dismukes |first6=G. Charles
 |last7=Bhattacharya |first7=Debashish
 |date=June 2016
 |title=The unexpected extremophile: Tolerance to fluctuating salinity in the green alga ''Picochlorum'' |journal=Algal Research
 |volume=16 |pages=465–472 |doi=10.1016/j.algal.2016.04.003|bibcode=2016AlgRe..16..465F
 }}
* {{Cite journal
 |last1=Fučíková |first1=Karolina
 |last2=Pažoutová |first2=Marie
 |last3=Rindi |first3=Fabio
 |date=2015
 |title=Meiotic genes and sexual reproduction in the green algal class Trebouxiophyceae (Chlorophyta) |journal=Journal of Phycology
 |volume=51 |issue=3 |pages=419–430 |doi=10.1111/jpy.12293|pmid=26986659
 |bibcode=2015JPcgy..51..419F
 }}
* {{Cite book
 |last1=Graham |first1=Linda E.
 |title=Algae
 |last2=Graham |first2=James M.
 |last3=Wilcox |first3=Lee W.
 |last4=Cook |first4=Martha E.
 |date=2022 |publisher=LJLM Press |isbn=978-0-9863-9354-9 |edition=4th}}
* {{Cite journal
 |last=Guiry |first=Michael D.
 |date=2024
 |title=How many species of algae are there? A reprise. Four kingdoms, 14 phyla, 63 classes and still growing |journal=Journal of Phycology
 |volume=60 |issue=2 |pages=214–228 |doi=10.1111/jpy.13431 |doi-access=free|pmid=38245909
 |bibcode=2024JPcgy..60..214G
 }}
* {{Cite journal
 |last1=Gulbrandsen |first1=Øyvind Sætren
 |last2=Andresen |first2=Ina Jungersen
 |last3=Krabberød |first3=Anders Kristian
 |last4=Bråte |first4=Jon
 |last5=Shalchian-Tabrizi |first5=Kamran
 |date=2021
 |title=Phylogenomic analysis restructures the Ulvophyceae |journal=Journal of Phycology
 |volume=57 |issue=4 |pages=1223–1233 |doi=10.1111/jpy.13168 |pmid=33721355 |doi-access=free |bibcode=2021JPcgy..57.1223G
 |hdl-access=free |hdl=11250/2778617}}
* {{Cite journal
 |last1=Hori |first1=Terumitsu
 |last2=Norris |first2=Richard E.
 |last3=Chihara |first3=Mitsuo
 |date=1986
 |title=Studies on the Ultrastructure and Taxonomy of the Genus ''Tetraselmis'' (Prasinophyceae) III. Subgenus ''Parviselmis'' |journal=Shokubutsugaku Zasshi
 |volume=99 |issue=1 |pages=123–135 |doi=10.1007/BF02488627 |bibcode=1986JPlR...99..123H
 |trans-journal=The Botanical Magazine, Tokyo}}
* {{Cite journal
 |last1=Joubert |first1=J. J.
 |last2=Rijkenberg |first2=F. H.
 |date=1971
 |title=Parasitic green algae |journal=Annual Review of Phytopathology
 |volume=9 |pages=45–64 |doi=10.1146/annurev.py.09.090171.000401}}
* {{Cite journal
 |last=Kapraun |first=Donald F.
 |date=April 2007
 |title=Nuclear DNA content estimates in green algal lineages: chlorophyta and streptophyta |journal=Annals of Botany
 |volume=99 |issue=4 |pages=677–701 |doi=10.1093/aob/mcl294 |pmc=2802934 |pmid=17272304}}
* {{Cite book
 |last=Lee |first=Robert Edward
 |title=Phycology |publisher=Cambridge University Press
 |date=2018 |isbn=978-1-3164-0721-9 |edition=5th |pages=133–230 |chapter=Chlorophyta |doi=10.1017/9781316407219}}
* {{Cite journal
 |last1=Leliaert |first1=Frederik
 |last2=Verbruggen |first2=Heroen
 |last3=Zechman |first3=Frederick W.
 |date=September 2011
 |title=Into the deep: new discoveries at the base of the green plant phylogeny |journal=BioEssays
 |volume=33 |issue=9 |pages=683–692 |doi=10.1002/bies.201100035 |pmid=21744372 |s2cid=40459076}}
* {{Cite journal
 |last1=Leliaert |first1=Frederik
 |last2=Smith |first2=David R.
 |last3=Moreau |first3=Hervé
 |last4=Herron |first4=Matthew D.
 |last5=Verbruggen |first5=Heroen
 |last6=Delwiche |first6=Charles F.
 |last7=De Clerck |first7=Olivier
 |date=2012
 |title=Phylogeny and molecular evolution of the green algae |url=http://images.algaebase.org/pdf/5628E58F0ecc431F0CsJm2B04CAD/49951.pdf |url-status=live |journal=Critical Reviews in Plant Sciences
 |volume=31 |issue=1
 |pages=1–46 |doi=10.1080/07352689.2011.615705 |bibcode=2012CRvPS..31....1L
 |s2cid=17603352 |archive-url=https://web.archive.org/web/20150626102452/http://images.algaebase.org/pdf/5628E58F0ecc431F0CsJm2B04CAD/49951.pdf |archive-date=2015-06-26}}
* {{Cite journal
 |last1=Lewin |first1=R. A.
 |last2=Krienitz |first2=L.
 |last3=Goericke |first3=R.
 |last4=Takeda |first4=H.
 |last5=Hepperle |first5=D.
 |date=2000
 |title=''Picocystis salinarum'' gen. et sp. nov. (Chlorophyta) – a new picoplanktonic green alga |journal=Phycologia
 |volume=39 |issue=6 |pages=560–565 |doi=10.2216/i0031-8884-39-6-560.1|bibcode=2000Phyco..39..560L
 }}
* {{Cite journal
 |last1=Lewis |first1=Louise A.
 |last2=McCourt |first2=Richard M.
 |date=2004
 |title=Green algae and the origin of land plants |journal=American Journal of Botany
 |volume=91 |issue=10 |pages=1535–1556 |doi=10.3732/ajb.91.10.1535 |pmid=21652308 |doi-access=free}}
* {{Cite journal
 |last1=Lewis |first1=Louise A.
 |last2=Lewis |first2=Paul O.
 |date=December 2005
 |title=Unearthing the molecular phylodiversity of desert soil green algae (Chlorophyta) |journal=Systematic Biology
 |volume=54 |issue=6 |pages=936–947 |doi=10.1080/10635150500354852 |pmid=16338765 |doi-access=free}}
* {{Cite journal
 |last1=Li |first1=Linzhou
 |last2=Wang |first2=Sibo
 |last3=Wang |first3=Hongli
 |last4=Sahu |first4=Sunil Kumar
 |last5=Marin |first5=Birger
 |last6=Li |first6=Haoyuan
 |last7=Xu |first7=Yan
 |last8=Liang |first8=Hongping
 |last9=Li |first9=Zhen
 |last10=Cheng |first10=Shifeng
 |last11=Reder |first11=Tanja
 |last12=Çebi |first12=Zehra
 |last13=Wittek |first13=Sebastian
 |last14=Petersen |first14=Morten
 |last15=Melkonian |first15=Barbara
 |last16=Du |first16=Hongli
 |last17=Yang |first17=Huanming
 |last18=Wang |first18=Jian
 |last19=Wong |first19=Gane Ka-Shu
 |last20=Xu |first20=Xun
 |last21=Liu |first21=Xin
 |last22=Van de Peer |first22=Yves
 |last23=Melkonian |first23=Michael
 |last24=Liu |first24=Huan
 |display-authors=10
 |date=September 2020
 |title=The genome of ''Prasinoderma coloniale'' unveils the existence of a third phylum within green plants |journal=Nature Ecology & Evolution
 |volume=4 |issue=9 |pages=1220–1231 |doi=10.1038/s41559-020-1221-7 |pmc=7455551 |pmid=32572216|bibcode=2020NatEE...4.1220L
 }}
* {{Cite book
 |last1=Lobban |first1=Christopher S.
 |title=The Biology of Seaweeds.
 |last2=Wynne |first2=Michael James |publisher=[[University of California Press]]
 |date=1981 |isbn=978-0-5200-4585-9 |series=Botanical Monograph Series 17. |name-list-style=vanc}}
* {{Cite journal
 |last1=Lopes dos Santos |first1=Adriana
 |last2=Pollina |first2=Thibaut
 |last3=Gourvil |first3=Priscillia
 |last4=Corre |first4=Erwan
 |last5=Marie |first5=Dominique
 |last6=Garrido |first6=José Luis
 |last7=Rodríguez |first7=Francisco
 |last8=Noël |first8=Mary-Hélène
 |last9=Vaulot |first9=Daniel
 |last10=Eikrem |first10=Wenche
 |date=2017
 |title=Chloropicophyceae, a new class of picophytoplanktonic prasinophytes |journal=Sci Rep
 |volume=7 |issue=1 |pages=14019 |bibcode=2017NatSR...714019L |doi=10.1038/s41598-017-12412-5 |pmc=5656628 |pmid=29070840}}
* {{Cite journal
 |last1=López-Bautista |first1=Juan M.
 |last2=Rindi |first2=Fabio
 |last3=Guiry |first3=Michael D.
 |date=July 2006
 |title=Molecular systematics of the subaerial green algal order Trentepohliales: an assessment based on morphological and molecular data |journal=International Journal of Systematic and Evolutionary Microbiology
 |volume=56 |issue=7 |pages=1709–1715 |doi=10.1099/ijs.0.63990-0 |pmid=16825655 |doi-access=free |hdl-access=free |hdl=10379/9448}}
* {{Cite book
 |last1=Margulis |first1=Lynn
 |title=Kingdoms & Domains: An Illustrated Guide to the Phyla of Life on Earth
 |last2=Chapman |first2=Michael J.
 |date=2009 |publisher=Academic Press |isbn=978-0-1237-3621-5 |edition=4th |pages=200–201 |chapter=Pr-28 Chlorophyta}}
* {{Cite journal
 |last1=Marin |first1=Birger
 |last2=Melkonian |first2=Michael
 |date=April 2010
 |title=Molecular Phylogeny and Classification of the Mamiellophyceae class. nov. (Chlorophyta) based on Sequence Comparisons of the Nuclear- and Plastid-encoded rRNA Operons |journal=Protist
 |volume=161 |issue=2 |pages=304–336 |doi=10.1016/j.protis.2009.10.002 |pmid=20005168}}
* {{Cite journal
 |last=Marin |first=Birger
 |date=2012
 |title=Nested in the Chlorellales or Independent Class? Phylogeny and Classification of the Pedinophyceae (Viridiplantae) Revealed by Molecular Phylogenetic Analyses of Complete Nuclear and Plastid-encoded rRNA Operons |journal=Protist
 |volume=163 |issue=5 |pages=778–805 |doi=10.1016/j.protis.2011.11.004 |pmid=22192529}}
* {{Cite book
 |last1=Mattox |first1=K. R. |url=https://archive.org/details/systematicsofgre0000unse
 |title=Systematics of the Green Algae
 |last2=Stewart |first2=K. D.
 |date=1984 |publisher=Academic Press |isbn=0-1237-4040-1 |editor-last=Irvine |editor-first=D. E. G. |series=Systematics Association Special
 |volume=27 |pages=29–72 |chapter=Classification of the Green Algae: A Concept Based on Comparative Cytology |editor-last2=John |editor-first2=D. M. |chapter-url=https://archive.org/details/systematicsofgre0000unse/page/29/mode/1up |url-access=registration}}
* {{Cite journal
 |last1=Nakayama |first1=Takeshi
 |last2=Suda |first2=Shoichiro
 |last3=Kawachi |first3=Masanobu
 |last4=Inouye |first4=Isao
 |date=2007
 |title=Phylogeny and ultrastructure of ''Nephroselmis'' and ''Pseudoscourfieldia'' (Chlorophyta), including the description of ''Nephroselmis anterostigmatica'' sp. nov. and a proposal for the Nephroselmidales ord. nov. |journal=Phycologia
 |volume=46 |issue=6 |pages=680–697 |doi=10.2216/04-25.1|bibcode=2007Phyco..46..680N
 }}
* {{Cite journal
 |last=Nedelcu |first=Aurora M.
 |date=December 2001
 |title=Complex patterns of plastid 16S rRNA gene evolution in nonphotosynthetic green algae |journal=Journal of Molecular Evolution
 |volume=53 |issue=6 |pages=670–679 |bibcode=2001JMolE..53..670N |doi=10.1007/s002390010254 |pmid=11677627 |s2cid=21151223}}
* {{Cite journal
 |last1=Nishii |first1=Ichiro
 |last2=Miller |first2=Stephen M.
 |date=2010
 |title=''Volvox'': Simple steps to developmental complexity? |journal=Current Opinion in Plant Biology
 |volume=13 |issue=6 |pages=646–653 |doi=10.1016/j.pbi.2010.10.005 |pmid=21075047|bibcode=2010COPB...13..646N
 }}
* {{Cite book
 |last=Papenfuss |first=George F.
 |title=A century of progress in the natural sciences, 1853-1953
 |date=1955 |publisher=California Academy of Sciences |publication-place=San Francisco |pages=115–224 |chapter=The Classification of the Algae |chapter-url=https://archive.org/stream/centuryofprogres00cali#page/126/mode/1up}}
* {{Cite journal
 |last=Pascher |first=A.
 |date=1914
 |title=Über Flagellaten und Algen |url=https://www.biodiversitylibrary.org/item/138036#page/145/mode/1up |journal=Berichte der Deutschen Botanischen Gesellschaft
 |volume=32 |pages=136–160 |doi=10.1111/j.1438-8677.1914.tb07573.x |s2cid=257830577}}
* {{Cite book
 |last=Reichenbach |first=H. TH. L. |url=https://www.biodiversitylibrary.org/page/52898117
 |title=Conspectus Regni Vegetabilis per Gradus Naturales Evoluti
 |date=1828 |publisher=apud Carolum Cnobloch |publication-place=Lipsiae (Leipzig) |doi=10.5962/bhl.title.127418 |oclc=5359726}}
* {{Cite journal
 |last1=Rockwell |first1=Nathan C.
 |last2=Martin |first2=Shelley S.
 |last3=Li |first3=Fay-Wei
 |last4=Mathews |first4=Sarah
 |last5=Lagarias |first5=J. Clark
 |date=May 2017
 |title=The phycocyanobilin chromophore of streptophyte algal phytochromes is synthesized by HY2 |journal=The New Phytologist
 |volume=214 |issue=3 |pages=1145–1157 |doi=10.1111/nph.14422 |pmc=5388591 |pmid=28106912|bibcode=2017NewPh.214.1145R
 }}
* {{Cite journal
 |last=Round |first=F. E.
 |date=1971
 |title=The taxonomy of the Chlorophyta. II |journal=British Phycological Journal
 |volume=6 |issue=2 |pages=235–264 |doi=10.1080/00071617100650261 |doi-access=free}}
* {{Cite book
 |last=Smith |first=Gilbert M. |author-link=Gilbert Morgan Smith |url=https://archive.org/details/cryptogamicbotan031880mbp/page/12/mode/2up
 |title=Cryptogamic Botany
 |date=1938 |publisher=McGraw Hill Book Company |edition=1st
 |volume=1}}
* {{Cite journal
 |last1=Solovchenko |first1=Alexei
 |last2=Merzlyak |first2=Mark N.
 |last3=Khozin-Goldberg |first3=Inna
 |last4=Cohen |first4=Zvi
 |last5=Boussiba |first5=Sammy
 |date=2 August 2010
 |title=Coordinated carotenoid and lipid syntheses induced in ''Parietochloris incisa'' (Chlorophyta, Trebouxiophyceae) mutant deficient in Δ5 desaturase by nitrogen starvation and high light |url=https://www.bashanfoundation.org/contributions/Solovchenko-A/alexeitreboux.pdf |journal=Journal of Phycology
 |volume=46 |issue=4 |pages=763–772 |doi=10.1111/j.1529-8817.2010.00849.x|bibcode=2010JPcgy..46..763S
 }}
* {{Cite journal
 |last=Srivastava |first=Purnima
 |date=2002
 |title=Carbonaceous Megafossils from the Dholpura Shale, Uppermost Vindhyan Supergroup, Rajasthan: An Age Implication |url=http://palaeontologicalsociety.in/vol47/v9.pdf |journal=Journal of the Palaeontological Society of India
 |volume=47 |pages=97–105|doi=10.1177/0971102320020109
 }}
* {{Cite journal
 |last1=Tang |first1=Qing
 |last2=Pang |first2=Ke
 |last3=Yuan |first3=Xunlai
 |last4=Xiao |first4=Shuhai
 |date=February 2020
 |title=A one-billion-year-old multicellular chlorophyte |journal=Nature Ecology & Evolution
 |volume=4 |issue=4
 |pages=543–549 |doi=10.1038/s41559-020-1122-9 |pmc=8668152|bibcode=2020NatEE...4..543T
 }}
* {{Cite journal
 |last1=Tartar |first1=Aurélien
 |last2=Boucias |first2=Drion G.
 |last3=Adams |first3=Byron J.
 |last4=Becnel |first4=James J.
 |date=January 2002
 |title=Phylogenetic analysis identifies the invertebrate pathogen ''Helicosporidium'' sp. as a green alga (Chlorophyta) |journal=International Journal of Systematic and Evolutionary Microbiology
 |volume=52 |issue=1 |pages=273–279 |doi=10.1099/00207713-52-1-273 |pmid=11837312 |doi-access=free}}
* {{Cite journal
 |last=Umen |first=James G.
 |date=October 2014
 |title=Green algae and the origins of multicellularity in the plant kingdom |journal=Cold Spring Harbor Perspectives in Biology
 |volume=6 |issue=11 |pages=a016170 |doi=10.1101/cshperspect.a016170 |pmc=4413236 |pmid=25324214}}
* {{Cite book
 |last1=van den Hoek |first1=Christiaan |url=https://books.google.com/books?id=xuUoiFesSHMC
 |title=Algae: An Introduction to Phycology
 |last2=Mann |first2=D. G.
 |last3=Jahns |first3=H. M. |publisher=Cambridge University Press
 |date=1995 |isbn=978-0-5213-0419-1}}
* {{Cite journal
 |last1=Yamaguchi |first1=Haruyo
 |last2=Suda |first2=Shoichiro
 |last3=Nakayama |first3=Takeshi
 |last4=Pienaar |first4=Richard N.
 |last5=Chihara |first5=Mitsuo
 |last6=Inouye |first6=Isao
 |date=2010
 |title=Taxonomy of ''Nephroselmis viridis'' sp. nov. (Nephroselmidophyceae, Chlorophyta), a sister marine species to freshwater ''N. olivacea'' |journal=Journal of Plant Research
 |volume=124 |issue=1 |pages=49–62 |doi=10.1007/s10265-010-0349-y |pmid=20499263}}
* {{Cite journal
 |last1=Yamashita |first1=Felipe
 |last2=Baluška |first2=František
 |date=2023
 |title=Algal ocelloids and plant ocelli |journal=Plants
 |volume=12 |pages=61 |doi=10.3390/plants12010061 |doi-access=free|pmc=9824129 }}
* {{Cite journal
 |last1=Yang |first1=Zhiping
 |last2=Ma |first2=Xiaoya
 |last3=Wang |first3=Qiuping
 |last4=Tian |first4=Xiaolin
 |last5=Sun |first5=Jingyan
 |last6=Zhang |first6=Zhenhua
 |last7=Xiao |first7=Shuhai
 |last8=De Clerck |first8=Olivier
 |last9=Leliaert |first9=Frederik
 |last10=Zhong |first10=Bojian
 |date=September 2023
 |title=Phylotranscriptomics unveil a Paleoproterozoic-Mesoproterozoic origin and deep relationships of the Viridiplantae |journal=Nature Communications
 |volume=14 |issue=1 |pages=5542 |doi=10.1038/s41467-023-41137-5 |pmc=10495350 |pmid=37696791 |doi-access=free|bibcode=2023NatCo..14.5542Y
 }}
{{Refend}}

== Further reading ==
{{Wikispecies|Chlorophyta}}
{{Commons category|Chlorophyta}}
{{Refbegin}}
* {{Cite book |title=Seaweeds of the British Isles |vauthors=Burrows EM |date=1991 |publisher=Natural History Museum |isbn=978-0-5650-0981-6 |volume=2 (Chlorophyta) |location=London}}
* {{Cite book |title=Green Algae. Structure, Reproduction and Evolution in Selected Genera |vauthors=Pickett-Heaps JD |date=1975 |publisher=Sinauer Assoc. |location=Stamford, CT |pages=606}}
{{Refend}}

{{Life on Earth}}
{{Eukaryota|D.}}
{{Plant classification}}
{{Taxonbar|from=Q264543}}

[[Category:Chlorophyta|Chlorophyta]]
[[Category:Plant divisions]]
[[Category:Taxa named by Ludwig Reichenbach]]
[[Category:Green algae phyla]]