The Hoek, Mann and Jahns system is a system of taxonomy of

algae Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthesis, photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular ...

. It was first published in ''Algae: An Introduction to Phycology'' by Cambridge University Press in 1995.

Division Cyanophyta (= Cyanobacteria)

* Class

Cyanophyceae Cyanophyceae is a class of cyanobacteria Cyanobacteria ( ) are a group of autotrophic gram-negative bacteria that can obtain biological energy via oxygenic photosynthesis. The name "cyanobacteria" () refers to their bluish green (cyan) ...

:* Order

Chroococcales The Chroococcales () are an order of cyanobacteria in some classifications which includes the harmful algal bloom '' Microcystis aeruginosa''. Molecular data indicate that Chroococcales may be polyphyletic, meaning its members may not all belon ...

(e.g., ''

Cyanothece ''Cyanothece'' is a genus of unicellular, diazotrophic, oxygenic photosynthesizing cyanobacteria. Modern organisms and cellular organization In 1976, Jiří Komárek defined the prokaryotic cyanobacteria genus ''Cyanothece'' as distinct from '' ...

, Aphanothece,

Merismopedia ''Merismopedia'' (from the Greek ''merismos'' ivisionand the Greek ''pedion'' lain is a genus of cyanobacteria Cyanobacteria ( ) are a group of autotrophic gram-negative bacteria that can obtain biological energy via oxygenic photosynt ...

, Chroococcus, Gloeocapsa,

Microcystis ''Microcystis'' is a genus of freshwater cyanobacteria that includes the harmful algal bloom-forming '' Microcystis aeruginosa''. Over the last few decades, cyanobacterial blooms caused by eutrophication have become a major environmental proble ...

, Chamaesiphon'') :* Order

Pleurocapsales The Pleurocapsales are an order of coccooid cyanobacteria Cyanobacteria ( ) are a group of autotrophic gram-negative bacteria that can obtain biological energy via oxygenic photosynthesis. The name "cyanobacteria" () refers to their blu ...

(e.g., '' Cyanocystis, Pleurocapsa'') :* Order

Oscillatoriales The Oscillatoriales are an order of cyanobacteria. References

Oscillatoriales, Bacteria orders {{cyanobacteria-stub ...

(e.g., ''

Oscillatoria ''Oscillatoria'' is a genus of filamentous cyanobacteria. It is often found in freshwater environments. Its name refers to the oscillating motion of its filaments as they slide against each other to position the colony to face a light source. ...

Lyngbya ''Lyngbya'' is a genus of cyanobacteria, unicellular autotrophs that form the basis of the oceanic food chain. As a result of recent genetic analyses, several new genera were erected from this genus: ''e.g.'', '' Moorea'', '' Limnoraphis'', '' O ...

, Microcoleus'') :* Order

Nostocales The Nostocales are an order of cyanobacteria Cyanobacteria ( ) are a group of autotrophic gram-negative bacteria that can obtain biological energy via oxygenic photosynthesis. The name "cyanobacteria" () refers to their bluish green (c ...

(e.g., ''

Nostoc ''Nostoc'', also known as star jelly, troll's butter, spit of moon, fallen star, witch's butter (not to be confused with the fungi commonly known as witches' butter), and witch's jelly, is the most common genus of cyanobacteria found in a variety ...

Anabaena ''Anabaena'' is a genus of filamentous cyanobacteria that exist as plankton. They are known for nitrogen-fixing abilities, and they form symbiotic relationships with certain plants, such as the mosquito fern. They are one of four genera of cyan ...

, Aphanizomenon, Scytonema, Rivularia'') :* Order

Stigonematales The Rivulariaceae are a family of cyanobacteria within the Nostocales in which the filaments (trichomes) are tapered from wider at the base to narrower at the tip. The type species is '' Rivularia haematites'' (Dc) C. A. Agardh. Genera , WoR ...

(e.g., '' Stigonema'')

Division Prochlorophyta

* Class Prochlorophyceae (e.g., ''

Prochloron ''Prochloron'' (from the Greek ''pro'' (before) and the Greek ''chloros'' (green) ) is a genus of unicellular oxygenic photosynthetic prokaryotes commonly found as an extracellular symbiont on coral reefs, particularly in didemnid ascidians (sea ...

Prochlorococcus ''Prochlorococcus'' is a genus of very small (0.6 μm) marine cyanobacteria with an unusual pigmentation ( chlorophyll ''a2'' and ''b2''). These bacteria belong to the photosynthetic picoplankton and are probably the most abundant photosyn ...

Prochlorothrix ''Prochlorothrix hollandica'' is a species of cyanobacteria named under the ''Bacteriological Code'' in 1989. It is the only species in genus ''Prochlorothrix'', which is the only species in family Prochlorotrichaceae, which is the only family in ...

'')

Division Glaucophyta

* Class Glaucophyceae (e.g., ''

Cyanophora ''Cyanophora'' is a genus of glaucophytes, a group of rare but evolutionarily significant freshwater microalgae. It includes the following species: * '' Cyanophora biloba'' * '' Cyanophora cuspidata'' * '' Cyanophora kugrensii'' * '' Cyanophora ...

, Glaucocystis'')

Division Rhodophyta

* Class

Bangiophyceae Bangiophyceae is a class of red algae that includes the order Bangiales and possibly Goniotrichales. In some classifications it is merged with the Florideophyceae to form the Rhodophyceae. The Bangiophyceae, as defined traditionally, are para ...

:* Order

Porphyridiales Porphyridiophyceae is a class of red algae. This class includes the monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include ...

(e.g., '' Porphyridium, Chroodactylon'') :* Order

Rhodochaetales Compsopogonophyceae is a class of red algae Red algae, or Rhodophyta (, ; ), make up one of the oldest groups of eukaryotic algae. The Rhodophyta comprises one of the largest Phylum, phyla of algae, containing over 7,000 recognized species wit ...

(e.g., '' Rhodochaete'') :* Order

Erythropeltidales Erythropeltidales is a red algae order in the class Compsopogonophyceae. Species *Erythropeltidales **Erythropeltidaceae **Erythrotrichiaceae ***''Chlidophyllon'' ***''Erythrocladia'' ***''Erythropeltis'' ***''Erythrotrichia'' ***''Porphyropsis'' ...

(e.g., ''

Erythrotrichia ''Erythrotrichia'' is a red algae genus in the family Erythrotrichiaceae. In Iceland, ''E. carnea'' is red listed as a vulnerable species A vulnerable species is a species which has been Conservation status, categorized by the International U ...

'') :* Order Compsogonales :* Order

Bangiales Bangiales is an order of multicellular red algae of the class Bangiophyceae containing the families Bangiaceae, Granufilaceae, and possibly the extinct genus ''Rafatazmia'' with one species, ''Rafatazmia chitrakootensis''. They are one of the ...

(e.g., ''

Porphyra ''Porphyra'' is a genus of coldwater seaweeds that grow in cold, shallow seawater. More specifically, it belongs to red algae phylum of laver species (from which comes laverbread), comprising approximately 70 species.Brodie, J.A. and Irvine, L ...

Bangia ''Bangia'' is an extant genus of division Rhodophyta that grows in marine or freshwater habitats. ''Bangia'' has small thalli with rapid growth and high reproductive output, and exhibits behavior characteristic of r-selected species. The plants ...

'') * Class

Florideophyceae Florideophyceae is a class of exclusively multicellular red algae. They were once thought to be the only algae to bear pit connections, but these have since been found in the filamentous stage of the Bangiaceae. They were also thought only to ex ...

:* Order Acrochaetiales (e.g., ''

Audouinella ''Audouinella'', also known as black algae, is a widespread genus of red algae, found in marine and freshwater environments. The form known as "''black brush algae''" (or "''black beard algae''", ''BBA'' for short) is a particular nuisance in ...

'') :* Order

Palmariales Palmariales is an order of marine algae. It includes the edible seaweed dulse ('' Palmaria palmata''). References {{Authority control Florideophyceae Red algae orders ...

(e.g., '' Palmaria, Rhodophysema'') :* Order

Nemaliales Nemaliales is an order of red algae. It holds approximately 286 species. Families As accepted by AlgaeBase (with amount of species per genus); * Suborder Galaxaurineae (117) **Galaxauraceae - 58 spp. **Scinaiaceae Scinaiaceae is a family ...

(e.g., '' Nemalion,

Galaxaura ''Galaxaura'' is a genus of thalloid red algae. Dichotomous branches are formed; the medulla has a filamentous construction. It may be related to the fossil Gymnocodiaceae. The genus has cosmopolitan distribution. Species As accepted by WoRMS ...

'') :* Order

Batrachospermales Batrachospermales is an order of red algae Red algae, or Rhodophyta (, ; ), make up one of the oldest groups of eukaryotic algae. The Rhodophyta comprises one of the largest Phylum, phyla of algae, containing over 7,000 recognized species with ...

(e.g., ''

Lemanea ''Lemanea'' is a genus of freshwater red algae, in the order Batrachospermales. Both species are considered to be widespread in the northern hemisphere. Although placed in the Rhodophyta (red algae) it in fact is green in colour. Description '' ...

Batrachospermum ''Batrachospermum'' is a genus of red algae from the family ''Batrachospermaceae''. Due to its complex biological life cycle, descriptions of the taxon typically focus on gametophytes, while sporophytes, i.e., carposporophytes, are filamentous st ...

'') :* Order

Corallinales Coralline algae are red algae in the order Corallinales. They are characterized by a thallus that is hard because of calcareous deposits contained within the cell walls. The colors of these algae are most typically pink, or some other shade of re ...

(e.g., '' Lithophyllum, Jania'') :* Order Hildebrandiales :* Order

Bonnemaisoniales Bonnemaisoniales is an order of red algae in the class Florideophyceae. It includes 2 families; * Bonnemaisoniaceae - 25 spp. * Naccariaceae - 7 spp. The order has cosmopolitan distribution In biogeography, a cosmopolitan distribution i ...

:* Order Gelidiales (e.g., ''

Gelidium ''Gelidium'' is a genus of thalloid red algae comprising 134 species. Its members are known by a number of common names.Recorded common names are tengusa, makusa, genso, niu mau tsai, japansche scheleiachtige mos, steen-or klipbloem, hay tsay, ol ...

'') :* Order

Gigartinales Gigartinales is a red algae order in the class Florideophyceae Florideophyceae is a class of exclusively multicellular red algae. They were once thought to be the only algae to bear pit connections, but these have since been found in the fila ...

(e.g., '' Acrosymphyton, Dumontia,

Chondrus ''Chondrus'' is a genus of red algae containing 11 accepted species: *'' Chondrus armatus'' (Harvey) Okamura *''Chondrus canaliculatus'' (C.Agardh) Greville *''Chondrus crispus'' Stackhouse *''Chondrus elatus ''Chondrus'' is a genus of red a ...

, Mastocarpus'') :* Order

Gracilariales Gracilariales is an order of red algae. References Red algae orders {{Rhodophyta-stub ...

:* Order

Ahnfeltiales Ahnfeltiales is an order of red algae belonging to the class Florideophyceae Florideophyceae is a class of exclusively multicellular red algae. They were once thought to be the only algae to bear pit connections, but these have since been fou ...

:* Order Rhodymeniales (e.g., '' Chylocladia'') :* Order

Ceramiales Ceramiales is an order of red algae. It was established by Friedrich Oltmanns in 1904. Families * Callithamniaceae Kützing, 1843 * Ceramiaceae Dumortier, 1822 * Choreocolacaceae Sturch * Dasyaceae Kützing, 1843 * Delesseriaceae Bory, 1828 * ...

(e.g., ''

Polysiphonia ''Polysiphonia'', known as red hair algae, is a genus of filamentous red algae with about 19 species on the coasts of the British Isles and about 200 species worldwide, including Crete in Greece, Antarctica and Greenland. Its members are known by ...

, Callithamnion, Ceramium, Hypoglossum'')

Division Heterokontophyta

* Class

Chrysophyceae The Chrysophyceae, usually called chrysophytes, chrysomonads, golden-brown algae, or golden algae, are a large group of algae, found mostly in freshwater. Golden algae is also commonly used to refer to a single species, '' Prymnesium parvum'', wh ...

:* Order

Ochromonadales Ochromonadales is an order of single-celled algae belonging to the class Chrysophyceae, also known as golden algae. Initially it contained numerous groups of flagellates that were not closely related. During the late 20th century, advancements i ...

(e.g., ''

Ochromonas ''Ochromonas'' is a genus of algae belonging to the family Ochromonadaceae. The genus has cosmopolitan distribution. Chlorosulfolipids, a class of biologically active compounds, was first discovered in some ''Ochromonas'' species. Species Ac ...

, Pseudokephyrion,

Dinobryon ''Dinobryon'' is a type of microscopic algae. It is one of the 22 genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In ...

'') :* Order Mallomonadales (= Class

Synurophyceae The synurids (order Synurales) are a small group of heterokont algae, found mostly in freshwater environments, characterized by cells covered in silica scales. Characteristics They are covered in silicate scales and spines. In ''Synura'', thes ...

, e.g., ''

Mallomonas ''Mallomonas'' is a genus comprising unicellular Algae, algal eukaryotes and characterized by their intricate cell coverings made of silica scales and bristles. The group was first named and classified by Dr. Maximilian Perty in 1852. These organ ...

Synura ''Synura'' is a genus of Colony (biology), colonial chrysomonad algae covered with silica scales. It is the most conspicuous genus of the order Synurales. Description Species of ''Synura'' form microscopic, spherical colonial organism, colonies, ...

'') :* Order

Pedinellales Pedinellales ( ICN) or Pedinellida (ICZN) is a group of single-celled algae found in both marine environments and freshwater. These are found in both freshwater and marine environments, and most genera are sessile, attached by posterior stalks. ...

(= Class Pedinellophyceae, e.g., '' Pedinella'') :* Order Chrysamoebidales (e.g., '' Rhizochrysis, Chrysarachnion'') :* Order Chrysocapsales (e.g., '' Chrysocapsa,

Hydrurus ''Hydrurus'' is a genus of algae belonging to the family Hydruraceae. The genus has almost cosmopolitan distribution In biogeography, a cosmopolitan distribution is the range of a taxon that extends across most or all of the surface of the ...

'') :* Order

Chrysosphaerales Chrysosphaerales is an order of Chrysophyceae The Chrysophyceae, usually called chrysophytes, chrysomonads, golden-brown algae, or golden algae, are a large group of algae, found mostly in freshwater. Golden algae is also commonly used to refe ...

(e.g., '' Chrysosphaera'') :* Order

Phaeothamniales Phaeothamniales is an order of alga in the Ochrophyta Ochrophytes, also known as heterokontophytes or stramenochromes, are a phylum of algae. They are the photosynthetic stramenopiles, a group of eukaryotes, organisms with a cell nucleus, cha ...

(e.g., '' Phaeothamnion, Thallochrysis'') * Class Parmophyceae :* Order

Parmales The Parmales are an order of marine microalgae within the Bolidophyceae class. They are found worldwide and characterized by a cell wall composed of 5-8 interlocking silica plates with distinct forms. They were initially thought to be loricate ch ...

(e.g., '' Pentalamina'') * Class Sarcinochrysidophyceae :* Order Sarcinochrysidales (e.g., '' Ankylochrysis, Sarcinochrysis, Nematochrysis'') * Genus '' Pelagococcus'' (relative of the Chrysophyceae) * Class

Xanthophyceae Yellow-green algae or the Xanthophyceae (xanthophytes) are an important group of heterokont algae. Most live in fresh water, but some are found in marine and soil habitats. They vary from single-celled flagellates to simple colonial and filamen ...

:* Order Chloramoebales (e.g., '' Chloromeson'') :* Order Rhizochloridales (e.g., '' Rhizochloris, Myxochloris'') :* Order Heterogloeales (e.g., '' Gloeochloris'') :* Order Mischococcales (e.g., '' Chloridella, Botrydiopsis, Characiopsis, Ophiocytium'') :* Order Tribonematales (e.g., '' Tribonema, Heterococcus, Heterodendron'') :* Order Botrydiales (e.g., '' Botrydium'') :* Order Vaucheriales (e.g., ''

Vaucheria ''Vaucheria'' is a genus of Xanthophyceae or yellow-green algae known as water felt. It is one of only two genera in the family Vaucheriaceae. The type species of the genus is '' Vaucheria disperma''. The genus was circumscribed by Augustin Py ...

'') * Class

Eustigmatophyceae Eustigmatophytes are a small group (17 genera; ~107 species) of eukaryotic forms of algae that includes marine, freshwater and soil-living species. All eustigmatophytes are unicellular, with coccoid cells and polysaccharide cell walls. Eus ...

(e.g., '' Ellipsoidion, Eustigmatos Pleurochloris">Pleurochloris.html" ;"title=" Pleurochloris"> Pleurochloris Polyedriella, Vischeria, Chlorobotrys, Nannochloropsis'') * Class Bacillariophyceae (= Diatomophyceae) :* Order Pennales (e.g., ''Navicula, Gyrosigma, Achnanthes, Tabellaria, Nitzchia, Surirella'') :* Order

Centrales The Coscinodiscophyceae are a proposed class(s) of diatoms. They are similar to the Centrales, a traditional, paraphyletic subdivision of the heterokont algae known as diatoms. The order is named for the shape of the cell walls (or valves or fr ...

(e.g., '' Coscinodiscus,

Thalassiosira ''Thalassiosira'' is a genus of centric diatoms, comprising over 100 marine and freshwater species. It is a diverse group of photosynthetic eukaryotes that make up a vital part of marine and freshwater ecosystems, in which they are key primary pr ...

, Stephanodiscus, Cerataulus, Triceratium, Odontella, Rhizosolenia'') * Class

Raphidophyceae The raphidophytes, formally known as Raphidophycidae or Raphidophyceae (formerly referred to as Chloromonadophyceae and Chloromonadineae), are a small group of eukaryotic algae that includes both marine and freshwater species. All raphidophyte ...

(e.g., '' Chatonella, Gonyostomum, Merotrichia, Vacuolaria, Fibrocapsa'') * Class

Dictyochophyceae Dictyochophyceae sensu lato is a photosynthetic lineage of heterokont The stramenopiles, also called heterokonts, are protists distinguished by the presence of stiff tripartite external hairs. In most species, the hairs are attached to flage ...

(e.g., ''

Dictyocha ''Dictyocha'' is a genus of silicoflagellates, marine photosynthetic unicellular protists that take the form of either flagellates or axopodial amoebae. Described by Ehrenberg in 1837, ''Dictyocha'' contains many important species of the marine ...

'') * Class

Phaeophyceae Brown algae (: alga) are a large group of multicellular algae comprising the class Phaeophyceae. They include many seaweeds located in colder waters of the Northern Hemisphere. Brown algae are the major seaweeds of the temperate and polar regio ...

:* Order

Ectocarpales Ectocarpales is a very large order (biology), order in the brown algae (class Phaeophyceae). The order includes families with pseudoparenchymatous (Splachnidiaceae) or true parenchymatous (Scytosiphonaceae) tissue. Pseudoparenchymatous refers t ...

(e.g., '' Phaeostroma, Spongonema,

Ectocarpus ''Ectocarpus'' is a genus of filamentous brown alga that includes a model organism for the genomics of multicellularity. Among possible model organisms in the brown algae, ''Ectocarpus'' was selected for the relatively small size of its mature th ...

'') :* Order

Sphacelariales Sphacelariales is an order of brown algae Brown algae (: alga) are a large group of multicellular algae comprising the class (biology), class Phaeophyceae. They include many seaweeds located in colder waters of the Northern Hemisphere. Brown ...

(e.g., ''

Sphacelaria ''Sphacelaria'' is a genus of brown macroalgae (or seaweed) in the family Sphacelariaceae. Taxonomy and nomenclature The genus and its type species (''Sphacelaria reticulata'') were briefly described by Hans Christian Lyngbye in Florae Danicae ...

'') :* Order Syringodermatales :* Order

Dictyotales Dictyotaceae is large family of brown algae (class Phaeophyceae). It is the only family in the monotypic order Dictyotales (). Members of this family generally prefer warmer waters than other brown algae and are prevalent in tropical and subtro ...

(e.g., ''

Dictyota ''Dictyota'' is a genus of brown seaweed in the family Dictyotaceae. Species are predominantly found in tropical and subtropical seas, and are known to contain numerous chemicals (diterpenes) which have potential medicinal value. As at the end ...

'') :* Order Scytosiphonales (e.g., '' Scytosiphon'') :* Order Cutleriales (e.g., '' Cutleria'') :* Order Dictyosiphonales (e.g., '' Dictyosiphon'') :* Order Chordariales (e.g., '' Sphaerotrichia'', '' Liebmania'', ''

Elachista ''Elachista'' is a genus of gelechioid moths described by Georg Friedrich Treitschke in 1833. It is the type genus of the grass-miner moth family (Elachistidae). This family is sometimes (in particular in older sources) circumscribed very loos ...

'') :* Order Sporochnales :* Order

Desmarestiales Desmarestiales is an order in the brown algae (Phaeophyceae). Members of this order have terete or ligulate (flat) pinnately branched thalli attached by discoid holdfasts. They have a sporophytic thallus usually aggregated to form a pseud ...

(e.g., ''

Desmarestia ''Desmarestia'' is a genus of brown algae found worldwide. It is also called acid weed, acid kelp, acidweed, ', sea sorrel, (), ', mermaid's hair, landlady's wig, or '. However, 'sea sorrel' can also specifically refer to ''Desmarestia virid ...

'') :* Order

Laminariales Kelps are large brown algae or seaweeds that make up the order Laminariales. There are about 30 different genera. Despite its appearance and use of photosynthesis in chloroplasts, kelp is technically not a plant but a stramenopile (a group conta ...

(e.g., ''

Laminaria ''Laminaria'' is a genus of brown algae, brown seaweed in the order Kelp, Laminariales (kelp), comprising 31 species native to the north Atlantic and northern Pacific Oceans. This economically important genus is characterized by long, leathery L ...

, Chorda'') :* Order

Fucales The Fucales (fucoids) are an order in the brown algae (class Phaeophyceae). The list of families in the Fucales, as well as additional taxonomic information on algae, is publicly accessible at Algaebase. The class Phaeophyceae is included wit ...

(e.g., ''

Fucus ''Fucus'' is a genus of brown algae found in the intertidal zones of rocky seashores almost throughout the world. Description and life cycle The thallus is perennial with an irregular or disc-shaped holdfast or with haptera. The erect portion ...

, Hormosira'') :* Order Durvillaeales (e.g., ''

Durvillaea ''Durvillaea'' is a genus of large brown algae in the monotypic family Durvillaeaceae. All members of the genus are found in the southern hemisphere, including Australia, New Zealand, South America, and various subantarctic islands. ''Durvillaea ...

'') :* Order Ascoseirales * Class Bicocoecida (e.g., '' Pseudobodo,

Cafeteria A cafeteria, called canteen outside the U.S., is a type of food service location in which there is little or no waiting staff table service, whether in a restaurant or within an institution such as a large office building or school; a scho ...

'') * Class

Oomycetes The Oomycetes (), or Oomycota, form a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms within the Stramenopiles. They are filamentous and heterotrophic, and can reproduce both sexually and asexually. Sexual reproduction o ...

(e.g., ''

Phytophthora ''Phytophthora'' (from Greek (''phytón''), "plant" and (), "destruction"; "the plant-destroyer") is a genus of plant-damaging oomycetes (water molds), whose member species cause economic losses on crops worldwide, as well as environmental dam ...

'') * Class Hyphochytridiomycetes * Class

Labyrinthulomycetes Labyrinthulomycetes (ICNafp) or Labyrinthulea (ICZN) is a class of protists that produce a network of filaments or tubes, which serve as tracks for the cells to glide along and absorb nutrients for them. The two main groups are the labyrinthul ...

Division Haptophyta (= Prymnesiophyta)

* Class

Haptophyceae The haptophytes, classified either as the Haptophyta, Haptophytina or Prymnesiophyta (named for ''Prymnesium''), are a clade of algae. The names Haptophyceae or Prymnesiophyceae are sometimes used instead. This ending implies classification at t ...

:* Order

Prymnesiales Prymnesiales is an order of Haptophyceae. It currently consists of three families: * Prymnesiaceae * Chrysochromulinaceae * Chrysoculteraceae References

Haptophyte orders Haptista orders {{Haptophyte-stub ...

(e.g., ''

Chrysochromulina ''Chrysochromulina'' is a genus of haptophytes. This phytoplankton is distributed globally in brackish and marine waters across approximately 60 known species. All ''Chrysochromulina'' species are phototrophic, however some have been shown to b ...

Prymnesium ''Prymnesium'' is a genus of haptophytes, including the species '' Prymnesium parvum''. The genus is a unicellular motile alga. It is ellipsoidal in shape one flagellum is straight and there are two longer ones which enable movement. The name L ...

, Corymbellus,

Phaeocystis ''Phaeocystis'' is a genus of algae belonging to the Prymnesiophyte class and to the larger division of Haptophyta. It is a widespread marine phytoplankton and can function at a wide range of temperatures ( eurythermal) and salinities (euryhali ...

'') :* Order

Isochrysidales Isochrysidales is an order of Haptophyceae The haptophytes, classified either as the Haptophyta, Haptophytina or Prymnesiophyta (named for ''Prymnesium''), are a clade of algae. The names Haptophyceae or Prymnesiophyceae are sometimes used i ...

(e.g., '' Chrysotila, Pleurochrysis'' ''Hymenomonas''">Hymenomonas.html" ;"title=" ''Hymenomonas"> ''Hymenomonas'' :* Order Coccolithophorales (e.g., ''Emiliania (coccolithophore), Emiliania, Syracosphaera, Discosphaera'') :* Order Pavlovales (e.g., ''Pavlova (alga), Pavlova'')

Division Cryptophyta

* Class

Cryptophyceae The cryptophyceae are a class of algae, most of which have plastids. About 230 species are known, and they are common in freshwater, and also occur in marine and brackish habitats. Each cell is around 10–50 μm in size and flattened in shape ...

(e.g., ''

Cryptomonas ''Cryptomonas'' is the name-giving genus of the Cryptomonads established by German biologist Christian Gottfried Ehrenberg in 1831. The algae are common in freshwater habitats and brackish water worldwide and often form blooms in greater depths o ...

Chilomonas ''Chilomonas'' is a genus of cryptophytes, including the species '' Chilomonas paramecium''. ''Chilomonas'' is a protozoan (heterotroph). ''Chilomonas'' is golden brown and has two flagella A flagellum (; : flagella) (Latin for 'whip' or ' ...

, Bjornbergiella'')

Division Dinophyta

* Class

Dinophyceae Dinophyceae is a class of dinoflagellates. Taxonomy * Class Dinophyceae Pascher 1914 eridinea Ehrenberg 1830 stat. nov. Wettstein; Blastodiniphyceae Fensome et al. 1993 orthog. emend.** Order Haplozoonales aplozooidea Poche 1913*** Famil ...

:* Order

Gymnodiniales The Gymnodiniales are an order (biology), order of dinoflagellates, of the class (biology), class Dinophyceae. Members of the order are known as gymnodinioid or gymnodinoid (terms that can also refer to any organism of similar morphology). They a ...

(e.g., ''

Gymnodinium ''Gymnodinium'' is a genus of dinoflagellates, a type of marine and freshwater plankton. It is one of the few naked dinoflagellates, or species lacking armor known as cellulosic plates. Since 2000, the species which had been considered to be part ...

Symbiodinium ''Symbiodinium'' is a genus of dinoflagellates that encompasses the largest and most prevalent group of endosymbiotic dinoflagellates known and have photosymbiotic relationships with many species. These unicellular microalgae commonly reside in ...

Polykrikos ''Polykrikos'' (from Greek “poly” - many, and “krikos” – ring or circle) is one of the genera of family Polykrikaceae that includes athecate pseudocolony-forming dinoflagellates. ''Polykrikos'' are characterized by a sophisticated bal ...

'') :* Order Gloeodiniales (e.g., '' Gloeodinium'') :* Order Thoracosphaerales (e.g., '' Thoracosphaera'') :* Order Phytodiniales (= Dinococcales, e.g., '' Phytodinium'') :* Order Dinotrichales (e.g., '' Dinoclonium'') :* Order Dinamoebidales (e.g., '' Stylodinium, Dinamoebidium'') :* Order

Noctilucales The Noctilucales are an order of marine dinoflagellates. They differ from most others in that the mature cell is diploid and its nucleus does not show a dinokaryotic organization. They show gametic meiosis. Characteristics These cells are ver ...

(e.g., ''

Noctiluca ''Noctiluca scintillans'' is a marine species of dinoflagellate that can exist in a green or red form, depending on the pigmentation in its vacuoles. It can be found worldwide, but its geographical distribution varies depending on whether it ...

'') :* Order

Blastodiniales Blastodiniales is an order of dinoflagellates belonging to the class Dinophyceae Dinophyceae is a class of dinoflagellates. Taxonomy * Class Dinophyceae Pascher 1914 eridinea Ehrenberg 1830 stat. nov. Wettstein; Blastodiniphyceae Fensome e ...

(e.g., '' Blastodinium'') :* Order

Syndiniales The Syndiniales are an order of early branching dinoflagellates (also known as Marine Alveolates, "MALVs"), found as parasites of crustaceans, fish, algae, cnidarians, and protists (ciliates, radiolarians, other dinoflagellates). The trophic f ...

:* Order

Peridiniales Peridiniales is an order of dinoflagellates. Families Species accepted by the World Register of Marine Species The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive cata ...

(e.g., ''

Peridinium ''Peridinium'' is a genus of motile, marine and freshwater dinoflagellates. Their morphology is considered typical of the armoured dinoflagellates, and their form is commonly used in diagrams of a dinoflagellate's structure. ''Peridinium'' can r ...

, Protoperidinium,

Ceratium The genus ''Ceratium'' is restricted to a small number (about 7) of freshwater dinoflagellate species. Previously the genus contained also a large number of marine dinoflagellate species. However, these marine species have now been assigned to a ...

Gonyaulax ''Gonyaulax'' is a genus of dinoflagellates with the type species ''Gonyaulax spinifera'' (Claparède et Lachmann) Diesing. ''Gonyaulax'' belongs to red dinoflagellates and commonly causes red tides. It can produce yesotoxins: for example, strai ...

'') :* Order Dynophysiales (e.g., ''

Dinophysis ''Dinophysis'' is a genus of dinoflagellatesAlgaeBase''Dinophysis'' Ehrenberg, 1839/ref> common in tropical, temperate, coastal and oceanic waters.Hallegraeff, G.M., Lucas, I.A.N. 1988: The marine dinoflagellate genus Dinophysis (Dinophyceae): ph ...

, Triposolenia, Amphisolenia, Ornithocercus, Histioneis'') :* Order

Prorocentrales The Prorocentrales are a small order of dinoflagellates. They are distinguished by having their two flagella inserted apically, rather than ventrally as in other groups. One flagellum extends forward and the other circles its base, and there a ...

(e.g., ''

Prorocentrum The Prorocentrales are a small order of dinoflagellates. They are distinguished by having their two flagella inserted apically, rather than ventrally as in other groups. One flagellum extends forward and the other circles its base, and there are ...

'')

Division Euglenophyta

* Class

Euglenophyceae Euglenophyceae (ICNafp, proposed as a class) or Euglenea (ICZN, proposed as a class) is an unranked clade of single-celled algae belonging to the phylum Euglenozoa. They have chloroplasts originated from an event of secondary endosymbiosis with ...

:* Order

Euglenales Euglenales (also known as Euglenida) is an order of flagellates in the phylum Euglenozoa. The family includes the most well-known euglenoid genus, '' Euglena'', as well as other common genera like '' Phacus'' and '' Lepocinclis''. Nomenclature ...

(e.g., ''

Euglena ''Euglena'' is a genus of Unicellular organism, single-celled, flagellate eukaryotes. It is the best-known and most widely studied member of the class Euglenoidea, a diverse group containing some 54 genera and at least 200 species. Species of '' ...

Astasia Astasis is a lack of motor coordination marked by an inability to stand, walk or even sit without assistance due to disruption of muscle coordination. The term ''astasia'' is interchangeable with ''astasis'' and is most commonly referred to as '' ...

'') :* Order

Eutreptiales Eutreptiaceae ( ICN) or Eutreptiidae (ICZN) is a family of algae in the class Euglenophyceae. It is the only family within the monotypic order Eutreptiales (ICN) or Eutreptiida (ICZN). It contains predominantly marine single-celled flagellates wi ...

:* Order Euglenamorphales :* Order Rhabdomonadales :* Order Sphenomonadales :* Order Heteronematales

Division Chlorarachniophyta

* Class Chlorarachniophyceae (e.g., '' Chlorarachnion'')

Division Chlorophyta

* Class

Prasinophyceae The prasinophytes are a group of unicellular green algae. Prasinophytes mainly include marine planktonic species, as well as some freshwater representatives.Sym, S. D. and Pienaar, R. N. 1993. The class Prasinophyceae. In Round, F. E. and Chapman ...

:* Order

Mamiellales Mamiellales are an order of green algae in the class Mamiellophyceae Mamiellophyceae is a class of green algae in the division Chlorophyta. The class contains three orders containing 25 species. * Order Dolichomastigales Marin & Melkoni ...

(e.g., '' Mamiella,

Bathycoccus ''Bathycoccus'' is a genus of green algae in the order Mamiellales Mamiellales are an order of green algae in the class Mamiellophyceae Mamiellophyceae is a class of green algae in the division Chlorophyta. The class contains three or ...

'') :* Order

Pseudoscourfieldiales Pseudoscourfieldiales is an order of green algae in the class Pyramimonadophyceae Pyramimonadophyceae is a class of green algae in the division Chlorophyta Chlorophyta is a division of green algae informally called chlorophytes. Descri ...

(e.g., ''

Nephroselmis ''Nephroselmis'' is a genus of green algae. It has been placed in the family Nephroselmidaceae, although a 2009 study suggests that it should be separated into its own class, Nephroselmidophyceae. One species can be an endosymbiont of ''Hatena ar ...

'') :* Order

Pyramimonadales Pyramimonadales are an order of green algae in the Chlorophyta. The chloroplasts of phototrophic euglenids probably came from endosymbiosis with a member of this order. Taxonomy * Family Polyblepharidaceae Dangeard 1888 ** Genus '' Amphoraemona ...

(e.g., ''

Pyramimonas ''Pyramimonas'' is a genus of green algae in the order Pyramimonadales. Phototropic euglenids inherited their plastids from a close relative of ''Pyramimonas'' which was an endosymbiont inside phagotrophic eukaryovorous euglenids. References

, Halosphaera, Pachysphaera'' '' Pterosperma'' ''

Mesostigma ''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. It is the only known genus in the class Mesostig ...

'' :* Genus ''

Pedinomonas ''Pedinomonas'' is a genus of green algae in the family Pedinomonadaceae.See the NCBIbr>webpage on Pedinomonas Data extracted from the The genus has also had species classified in ''Micromonas ''Micromonas'' is a genus of green algae in th ...

'' (sometimes classified in the class

Pedinophyceae Pedinophyceae is a class of green algae in the division Chlorophyta Chlorophyta is a division of green algae informally called chlorophytes. Description Chlorophytes are eukaryotic organisms composed of cells with a variety of coverings ...

, or Loxophyceae) :* Order

Chlorodendrales Chlorodendrales are an order of green, flagellated, thecate, unicellular eukaryotes, within the green algae class Chlorodendrophyceae.See the NCBIbr>webpage on Chlorodendrales Data extracted from the Prasinophyceae are defined by their cellula ...

(e.g., ''

Tetraselmis ''Tetraselmis'' is a genus of phytoplankton. ''Tetraselmis'' is a green algal genus within the order Chlorodendrales, and they are characterized by their green chloroplast, their four-flagellate cell bodies, the presence of a pyrenoid within the ...

'') * Class

Chlorophyceae The Chlorophyceae, also known as chlorophycean algae, are one of the classes of green algae, within the phylum Chlorophyta. They are a large assemblage of mostly freshwater and terrestrial organisms; many members are important primary producers i ...

:* Order

Volvocales Chlamydomonadales, also known as Volvocales, are an order of flagellated or pseudociliated green algae, specifically of the Chlorophyceae.See the NCBIbr>webpage on Chlamydomonadales Data extracted from the Chlamydomonadales can form planar or ...

ncluding the Tetrasporales">Tetrasporales.html" ;"title="ncluding the Tetrasporales">ncluding the Tetrasporales(e.g., ''Chlamydomonas, Chlorogonium, Hyalogonium, Gloeomonas, Diplostauron, Polytoma, Carteria, Brachiomonas, Lobomonas, Sphaerellopsis, Haematococcus, Phacotus, Pteromonas, Stephanosphaera,

Gonium ''Gonium'' (Greek: γωνία ''gonia'', "angle" or "corner") is a genus of colonial green algae, a member of the order Chlamydomonadales. The genus was first described by Otto Friedrich Müller in 1773, and is among the most common types of alg ...

Pandorina ''Pandorina'' is a genus of green algae in the family Volvocaceae. It is a common freshwater genus, and has a cosmopolitan distribution. Along with other algae such as '' Volvox'', '' Eudorina'' and ''Chlamydomonas'', it is a model organism for s ...

Eudorina ''Eudorina'' is a genus of green algae in the family Volvocaceae, containing about seven species. It has a cosmopolitan distribution in freshwater habitats. Description ''Eudorina'' colonies typically consist of 16, 32 or 64 cells, each of wh ...

Volvox ''Volvox'' is a polyphyletic genus of chlorophyte green algae in the family Volvocaceae. ''Volvox'' species form spherical colonies of up to 50,000 cells, and for this reason they are sometimes called globe algae. First reported by Antonie van L ...

, Pseudosphaerocystis'') :* Order

Chlorococcales Chlorococcales is a formerly recognized Order (biology), order of green algae in the Class (biology), class Chlorophyceae. , the type family Chlorococcaceae was placed in the order Chlamydomonadales. Conventionally, many groups of coccoid green ...

(e.g., '' Chlorococcum, Golenkinia,

Chlorella ''Chlorella'' is a genus of about thirteen species of single- celled or colonial green algae of the division Chlorophyta. The cells are spherical in shape, about 2 to 10 μm in diameter, and are without flagella. Their chloroplasts contain t ...

, Chodatella,

Oocystis ''Oocystis'' is a planktonic genus of mostly freshwater green algae of the Family (biology), family Oocystaceae. It is the type genus of its family. ''Oocystis'' is mostly found in freshwater habitats and has a cosmopolitan distribution. A few sp ...

Kirchneriella ''Kirchneriella'' is a genus of green algae in the family Selenastraceae. It is found in freshwater habitats, as phytoplankton or metaphyton. The genus name of ''Kirchneriella'' is in honour of Emil Otto Oskar von Kirchner (1851–1925), w ...

, Nephrocytium,

Actinastrum ''Actinastrum'' is a genus of freshwater green algae. It was first described by Gustaf Lagerheim in 1882. Members of the genus are commonly found in eutrophic freshwater ponds and lakes, and have a cosmopolitan distribution. Traditionally, ''Ac ...

, Crucigenia, Sphaerocystis,

Coccomyxa ''Coccomyxa'' is a genus of green algae in the family Coccomyxaceae. This genus is defined by their small, elliptical to spherical shape, and the presence of a simple parietal chloroplast. These features, along with their occurrence in various l ...

Scenedesmus ''Scenedesmus'' is a genus of green algae, in the class Chlorophyceae. They are colonial and non-motile. They are one of the most common components of phytoplankton in freshwater habitats worldwide. Taxonomy The starting point of ''Scenedesmus'' ...

Hydrodictyon The water net (genus ''Hydrodictyon'') is a taxon of freshwater green algae in the family Hydrodictyaceae. ''Hydrodictyon'' does well in clean, eutrophic water, and has become a nuisance in New Zealand, where it has been recently introduced. The ...

Pediastrum ''Pediastrum'' is a genus of green algae, in the family Hydrodictyaceae. It is a photoautotrophic, nonmotile coenobial green alga that inhabits freshwater environments. The name ''Pediastrum'' comes from the Greek root words ''pedion'', meaning ...

, Chlorosarcinopsis,

Cylindrocapsa ''Cylindrocapsa'' is a genus of green algae, specifically of the Chlorophyceae. It is commonly found in freshwater habitats. Virus-like particles have been found in a strain of one species, '' Cylindrocapsa geminella''. Description ''Cylindrocap ...

, Geminella, Binuclearia,

Radiofilum ''Radiofilum'' is a genus of green algae in the class Chlorophyceae. It is a freshwater genus; they are often found in soft, boggy or acidic waters. ''Radiofilum'' consists of unbranched filaments of cells, surrounded by a very thin mucilage lay ...

Sphaeroplea ''Sphaeroplea'' is a genus of green algae in the family Sphaeropleaceae. It was first circumscribed by the Swedish botanist Carl Adolph Agardh in 1824. Description ''Sphaeroplea'' consists of unbranched filaments of cells, one cell thick. Cell ...

Characiosiphon ''Characiosiphon'' is a genus of green algae in the family Characiosiphonaceae. It contains a single species, ''Characiosiphon rivularis''. ''Characiosiphon rivularis'' was first described by the Indian phycologist M. O. P. Iyengar in 1936. M ...

, Atractomorpha'') :* Order

Chaetophorales Chaetophorales is an order of green algae in the class Chlorophyceae. Algae in the order Chaetophorales consist of filamentous, branched algae. The thalli have two parts, a prostrate and upright section and the filaments are variously branched. T ...

(e.g., '' Uronema, Stigeoclonium,

Draparnaldia ''Draparnaldia'' is a genus of freshwater green algae in the family Chaetophoraceae. It forms branched chains of cells, termed filaments, surrounded by mucilage. It is a cosmopolitan distribution, cosmopolitan genus with wide distribution and it ...

, Schizomeris'') :* Order Oedogoniales (e.g., ''

Oedogonium ''Oedogonium'' is a genus of filamentous, free-living green algae. It was first discovered in the fresh waters of Poland in 1860 by W. Hilse, and later given its name by German scientist Karl Engelbrecht Hirn, K. E. Hirn. The morphology of ''Oed ...

'') * Class

Ulvophyceae The Ulvophyceae or ulvophytes are a class of green algae, distinguished mainly on the basis of Ultrastructure, ultrastructural morphology, Biological life cycle, life cycle and molecular phylogenetics, molecular phylogenetic data. The sea lettu ...

:* Order Codiolales (e.g., '' Chlorocystis,

Ulothrix ''Ulothrix'' is a genus of green algae in the family Ulotrichaceae. It is a common in fresh to marine habitats, particularly colder and temperate waters. It has a cosmopolitan distribution. The genus includes: * '' Ulothrix aequalis'' Guiry, ...

, Spongomorpha, Urospora,

Acrosiphonia ''Acrosiphonia'' is a genus of green algae in the family Ulotrichaceae.See the NCBI The National Center for Biotechnology Information (NCBI) is part of the National Library of Medicine (NLM), a branch of the National Institutes of Health ( ...

Monostroma ''Monostroma'' is a genus of marine green algae (seaweed) in the family Monostromataceae. As the name suggests, algae of this genus are monostromatic (single cell layered). '' Monostroma kuroshiense'', an algae of this genus, is commercially cu ...

'') :* Order

Ulvales Ulvales is an order of green alga The green algae (: green alga) are a group of chlorophyll-containing autotrophic eukaryotes consisting of the phylum Prasinodermophyta and its unnamed sister group that contains the Chlorophyta and Charoph ...

(e.g., ''

Ulva Ulva (; ) is a small island in the Inner Hebrides of Scotland, off the west coast of Mull. It is separated from Mull by a narrow strait, and connected to the neighbouring island of Gometra by a bridge. Much of the island is formed from Cen ...

Enteromorpha The sea lettuces comprise the genus ''Ulva'', a group of edible green algae that is widely distributed along the coasts of the world's oceans. The type species within the genus ''Ulva'' is ''Ulva lactuca'', ''lactuca'' being Latin for "lettuce ...

, Ulvaria, Acrochaete'') * Class Cladophorophyceae :* Order

Cladophorales Cladophorales are an order of green algae, in the class Ulvophyceae. The earliest known representative is ''Proterocladus antiquus'' from the Mesoproterozoic-Neoproterozoic boundary in North China. The order Cladophorales consists of filamentou ...

(e.g., ''

Cladophora ''Cladophora'' is a genus of reticulated filamentous green algae in the class Ulvophyceae. They may be referred to as reticulated algae, branching algae, or blanket weed. The genus has a worldwide distribution and is harvested for use as a food a ...

Chaetomorpha ''Chaetomorpha'' is a genus of green algae in the family Cladophoraceae.Guiry, M. D. (2004)''Chaetomorpha''.''In:'' Guiry, M. D. & Guiry, G. M. (2017). AlgaeBase. Accessed through: World Register of Marine Species on 9 August 2017. Members of thi ...

Rhizoclonium ''Rhizoclonium'' is a genus of green algae in the family Cladophoraceae Cladophoraceae are a family (biology), family of green algae in the order the Cladophorales.See the National Center for Biotechnology Information, NCBI]webpage on Cladopho ...

, Struvea, Valonia,

Siphonocladus ''Siphonocladus'' is a small genus of green algae in the family Siphonocladaceae. The algal body (thallus) is composed of long, club-shaped cells that divide by segregative cell division, followed by the formation of branches that break through ...

Dictyosphaeria ''Dictyosphaeria'' is a genus of green algae (class Ulvophyceae) in the family Siphonocladaceae. Taxonomy and nomenclature The genus ''Dictyosphaeria'' belongs to the order of Cladophorales and family Siphonocladaceae. It comprises a total of ...

'') * Class Bryopsidophyceae :* Order

Bryopsidales Bryopsidales is an order of green algae, in the class Ulvophyceae. It is a diverse group of mostly marine macroalgae. Characteristics The thallus is filamentous, highly branched, and may be packed into a mass. It is coenocytic, having multi-nu ...

(e.g., ''

Bryopsis ''Bryopsis'', often referred to as hair algae, is a genus of marine green algae in the family Bryopsidaceae. Species in the genus are macroscopic, siphonous marine green algae that are made up of units of single tubular filaments. They can form ...

, Pseudobryopsis,

Derbesia ''Derbesia'' is a genus of green algae in the family Derbesiaceae. The plant was originally known from different names applied to its larger sporophyte, ''Derbesia'', and its less conspicuous gametophyte A gametophyte () is one of the two a ...

Codium ''Codium'' is a genus of edible green macroalgae (or seaweed) under the order Bryopsidales. The genus name is derived from a Greek word that pertains to the soft texture of its thallus. One of the foremost experts on ''Codium'' taxonomy was P ...

'') :* Order Halimedales (e.g., '' Udotea, Penicillus,

Halimeda ''Halimeda'' is a genus of green macroalgae. The algal body (thallus) is composed of calcified green segments. Calcium carbonate is deposited in its tissues, making it inedible to most herbivores. However one species, ''Halimeda tuna'', was desc ...

Caulerpa ''Caulerpa'' is a genus of seaweeds in the family Caulerpaceae (among the green algae). They are unusual because they consist of only one cell with many cell nucleus, nuclei, making them among the biggest single cells in the world. Referring to ...

'') * Class Dasycladophyceae :* Order

Dasycladales Dasycladales is an Order (biology), order of large unicellular green algae in the class Ulvophyceae. It contains two families, the Dasycladaceae and the Polyphysaceae. These single celled algae are from 2 mm to 200 mm long. They liv ...

(e.g., ''

Acetabularia ''Acetabularia'' is a genus of green algae in the family Polyphysaceae. Typically found in subtropical waters, ''Acetabularia'' is a single-celled organism, but gigantic in size and complex in form, making it an excellent model organism for stud ...

Batophora ''Batophora'' is a genus of green algae in the family Dasycladaceae.See the NCBI The National Center for Biotechnology Information (NCBI) is part of the National Library of Medicine (NLM), a branch of the National Institutes of Health (NIH) ...

Dasycladus ''Dasycladus'' is a genus of green algae in the family '' Dasycladaceae''. ''Dasycladus'' is a marine species. References Ulvophyceae genera Dasycladaceae {{Ulvophyceae-stub ...

, Neomeris,

Cymopolia ''Cymopolia'' is a genus of green algae in the family Dasycladaceae.See the National Center for Biotechnology Information, NCBI]webpage on Cymopolia Data extracted from the References

Ulvophyceae genera Dasycladaceae {{Ulvophyceae-s ...

'') * Class Trentepohliophyceae :* Order

Trentepohliales Trentepohliaceae are a family (biology), family of green algae, and the only family in the order Trentepohliales. It is a member of the Ulvophyceaen green algae. The family is characterized by traits like net-like chloroplasts without pyrenoids, ...

(e.g., '' Trentepohlia,

Cephaleuros ''Cephaleuros'' is a genus of thalloid green algae comprising approximately 14 species. Its common name is red rust. ''Cephaleuros'' species are parasitic algae which grow within vascular plants, typically within the subtropics or tropics. Desc ...

'') * Class

Pleurastrophyceae The Pleurastrophyceae were a formerly recognized class of green algae, in the division Chlorophyta. It was created by Mattox and Stewart in 1984, containing four genera. More recent classifications tend to split the group. On the one hand, ''Te ...

:* Order Pleurastrales (e.g., ''

Trebouxia ''Trebouxia'' is a unicellular green alga. It is a photosynthetic organism that can exist in almost all habitats found in polar, tropical, and temperate regions.Erokhina, L. G., Shatilovich, A. V., Kaminskaya, O. P., & Gilichinskii, D. A. (2004 ...

Myrmecia Myrmecia can refer to: * ''Myrmecia'' (alga), genus of algae associated with lichens * ''Myrmecia'' (ant), genus of ants called bulldog ants * Myrmecia (skin), a kind of deep wart on the human hands or feet See also * '' Copromorpha myrmecias'' ...

, Friedmannia, Pleurastrosarcina,

Pleurastrum ''Pleurastrum'' is a genus of green algae, specifically of the Chlorophyceae. , it was the only genus in the family Pleurastraceae. Species , AlgaeBase AlgaeBase is a global species database of information on all groups of algae, both seaweed ...

Microthamnion ''Microthamnion'' is a genus of green algae in the family Microthamniaceae. It is found in freshwater habitats around the world, preferably with low levels of pollution; it is typically attached to solid substrates. Description ''Microthamnion' ...

'') * Position uncertain: :* Order

Prasiolales Prasiolales is an order (biology), order of green algae in the Class (biology), class Trebouxiophyceae. Members of this order are ecologically widespread and are found in freshwater, marine, and terrestrial habitats from the Arctic to the Antarct ...

(e.g., ''

Prasiola ''Prasiola'' is a genus of macroscopic green algae, found in a variety of habitats ranging from terrestrial, freshwater, to marine. The genus has a cosmopolitan distribution, ranging from the Arctic to the Antarctic. Plants belonging to the genu ...

'') * Class

Klebsormidiophyceae Klebsormidiales is an order of charophyte algae. Until Bierenbroodspot et al.'s phylogeny, it was the only order in the class Klebsormidiophyceae, sister of the Phragmoplastophyta. , AlgaeBase AlgaeBase is a global species database of infor ...

:* Order Klebsormidiales (e.g., ''

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

, Raphidonema,

Klebsormidium ''Klebsormidium'' is a genus of filamentous charophyte green algae comprising 20 species. The name was proposed in 1972 to resolve confusion in application and status of ''Hormidium'' and was given for the German botanist Georg Klebs, Georg Albre ...

'') :* Order

Coleochaetales Coleochaetaceae is a family of algae. It is the only family in the Coleochaetales, an order of parenchymous charophyte algae, within the class Coleochaetophyceae. It includes some of the closest multicellular relatives of land plants. It cont ...

(e.g., ''

Chaetosphaeridium ''Chaetosphaeridium'' is a genus of green algae. Several classifications have been proposed. Its traditional classification is in the order Coleochaetales, related to the genus '' Coleochaete''. AlgaeBase places it in the order Chaetosphaeridial ...

Coleochaete ''Coleochaete'' is a genus of parenchymatous charophyte green algae in the order Coleochaetales. They are haploid, reproduce both sexually and asexually, and have true multicellular organisation, with plasmodesmata communicating between adjacen ...

'') * Class

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. The Zygnematophyceae are the sister clade of the Embryophyta (l ...

:* Order

Zygnematales The Zygnematales ( (''zygós'') and νῆμα (''nḗma'') ( nom.), νήματος (''nḗmatos'') ( gen.)), also called the Conjugatales, are an order of green algae, comprising several thousand different species in two families. The larger fam ...

(e.g., ''

Spirogyra ''Spirogyra'' (common names include water silk, mermaid's tresses, and blanket weed) is a genus of filamentous charophyte green algae of the order Zygnematales, named for the helical or spiral arrangement of the chloroplasts that is charact ...

Mougeotia ''Mougeotia'' is a genus of filamentous charophyte green algae of the order Zygnematales. It is a common component of freshwater aquatic habitats around the world. Described in 1824 by Carl Adolph Agardh, its name honors the French botanist Jean- ...

Zygnema ''Zygnema'' is a genus of freshwater filamentous thalloid alga comprising about 100 species. A terrestrial species, ''Z. terrestre'', is known from India. ''Zygnema'' grows as a free-floating mass of filaments, although young plants may be found ...

Spirotaenia ''Spirotaenia'' is a genus of basal unicellular green algae that may be sister to the Chlorokybophyceae. It was previously considered to be part of the Zygnemataceae. It is sexually Isogamy#Conjugation, conjugating, a mode of reproduction that ...

Cylindrocystis ''Cylindrocystis'' is a genus of algae belonging to the family Mesotaeniaceae. The species of this genus are found in Europe and America. Species: *''Cylindrocystis angulatum'' *''Cylindrocystis cylindrospora'' *''Cylindrocystis diplospora'' ...

Netrium ''Netrium'' is a genus of algae belonging to the family Mesotaeniaceae The Mesotaeniaceae are a small family of unicellular green algae known as the "saccoderm desmids". The Mesotaeniaceae appear to be sister or ancestral to the Zygnemataceae. ...

'') :* Order

Desmidiales Desmidiales, commonly called the desmids (''Gr.'' ''desmos'', bond or chain), are an order in the Charophyta, a division of green algae in which the land plants ( Embryophyta) emerged. Desmids consist of single-celled (sometimes filamentous or ...

(e.g., ''

Cosmarium ''Cosmarium'' is a large genus of desmids (Desmidiaceae), a group of green algae closely related to the land plants (Embryophyta). Members of this genus are microscopic and found in freshwater habitats around the world. The name ''Cosmarium'' co ...

Gonatozygon ''Gonatozygon'' is a genus of green algae in the family Gonatozygaceae.See the NCBI The National Center for Biotechnology Information (NCBI) is part of the National Library of Medicine (NLM), a branch of the National Institutes of Health (N ...

Closterium ''Closterium'' is a genus of desmid, a group of charophyte green algae.See the NCBIbr>webpage on Closterium Data extracted from the It is placed in the family Closteriaceae. Species of ''Closterium'' are a common component of freshwater microal ...

, Pleurotaenium, Tetmemorus,

Euastrum ''Euastrum'' is a genus of green algae of the Desmidiaceae family.See the National Center for Biotechnology Information, NCBIbr>webpage on Euastrum Data extracted from the It lives in acidic waters. Description It is made of two, symmetrical ...

Micrasterias ''Micrasterias'' is a Cell (biology), unicellular green alga of the order Desmidiales. Its species vary in size reaching up to hundreds of microns. ''Micrasterias'' displays a bilateral symmetry, with two mirror image semi-cells joined by a narr ...

Cosmocladium ''Cosmocladium'' is a genus of freshwater green algae, specifically of the Desmidiaceae. Currently there are 7 accepted species, though there are 11 described. The holotype is '' Cosmocladium pulchellum'' Brébisson described in 1856. ''Cosmoclad ...

, Xanthidium,

Staurastrum ''Staurastrum'' is a large genus of desmids (Desmidiaceae), a group of green algae closely related to the land plants (Embryophyta). Members of this genus are microscopic and found in freshwater habitats around the world. The name ''Staurastrum'' ...

Desmidium ''Desmidium'' is a genus of green algae,See the NCBIbr>webpage on Desmidium Data extracted from the the type genus of the family Desmidiaceae. It has a cosmopolitan distribution in acidic, oligotrophic freshwater lakes and bogs. The genus name ...

, Hyalotheca, Spondylosium, Sphaerozosma, Onychonema'') * Class

Charophyceae Charophyceae is a class of charophyte green algae. AlgaeBase places it in division Charophyta. Extant (living) species are placed in a single order Charales, commonly known as "stoneworts" and "brittleworts". Fossil members of the class may be p ...

:* Order

Charales Charales is an order of freshwater green algae in the division Charophyta, class Charophyceae, commonly known as stoneworts. Depending on the treatment of the genus '' Nitellopsis'', living (extant) species are placed into either one family ( ...

(e.g., '' Chara, Lamprothamnium, Nitellopsis,

Nitella ''Nitella'' is a genus of charophyte green algae in the family Characeae. Species The species in the genus include: *'' Nitella abyssinica'' A. Braun * '' Nitella acuminata'' A. Braun ex Wallman *'' Nitella aemula'' A. Braun * '' Nitella ann ...

Tolypella ''Tolypella'' is a genus of green algae belonging to the family Characeae. The genus was described in 1857 by Alexander Braun. The genus has cosmopolitan distribution. Species: * ''Tolypella antarctica'' (A. Braun) R. Corillion, 1982 * ''Tolyp ...

'')

Note added in proof

In a note added in proof, an alternative classification is presented for the class Chlorophyceae: * Class Chlamydophyceae :*Order

:*Order

(e.g., '' Chlorococcum, Chlorosarcinopsis,

'' * Class

:* Order

Chlorellales The Chlorellales are an order of green algae in the class Trebouxiophyceae. The Chlorellales include mostly freshwater or terrestrial (rarely marine), coccoid algae. Molecular phylogenetic studies mostly tend to find Chlorellales to consist of t ...

(e.g., ''

, Atractomorpha'') * Class Oedogoniophyceae :*Order Oedogoniales (e.g., ''

'') Many examples of genus given in the book could not be assigned to one of these classes, because the

ultrastructural Ultrastructure (or ultra-structure) is the architecture of cells and biomaterials that is visible at higher magnifications than found on a standard optical light microscope. This traditionally meant the resolution and magnification range of a c ...

characteristics needed for their classification have not yet been studied.

References

External links

* {{Cite book , last=van den Hoek , first=C. , title=Algae: An Introduction to Phycology , last2=Mann , first2=D. G. , last3=Jahns , first3=Hans Martin , publisher=Cambridge University Press , year=1995 , isbn=9780521304191 Systems of algal taxonomy