List of C₄ plants

The following list presents known C₄ lineages by family, based on the overview by Sage (2016).[1] They correspond to single species or clades thought to have acquired the C₄ pathway independently. In some lineages that also include C₃ and C₃–C₄ intermediate species, the C₄ pathway may have evolved more than once.^[1]

Acanthaceae

The large acanthus family Acanthaceae includes one genus with C₄ species, found in dry habitats from Africa to Asia.^[8]

• Blepharis – 15 C₄ species, 1–4 origins

Aizoaceae

While many species in the ice plant family

The amaranth family Amaranthaceae (including the former goosefoot family Chenopodiaceae) contains around 800 known C₄ species, which belong to 14 distinct lineages in seven subfamilies. This makes Amaranthaceae the family with most C₄ species and lineages among the eudicots.^[1] Suaeda aralocaspica and species of the genus Bienertia use a particular, single-cell type of C₄ carbon fixation.^[1][10]

• Aerva (Amaranthoideae) – 4 C₄ species^[11]
• Alternanthera (Gomphrenoideae) – 17 C₄ species (also includes C₃–C₄ intermediates)^[11]
• Amaranthus (Amaranthoideae) – 90 C₄ species^[11]
• Atriplex (Chenopodioideae) – around 180 C₄ species^[12]
• Camphorosmoideae) – 24 C₄ species (also includes one C₃–C₄ intermediate), 1–2 origins^[13]
• Bienertia (Suaedoideae) – 3 C₄ species^[10][14]
• Caroxyleae (syn. Caroxyloneae, Salsoloideae) – 157 C₄ species^[15][16]
• Gomphrenoids (Gomphrenoideae) – 138 C₄ species^[11]
• Salsoleae (Salsoloideae) – 158 C₄ species, 2–4 origins^[15][16]
• Suaeda aralocaspica (Suaedoideae)^[10]
• Suaeda sect. Salsina – 30 C₄ species^[10]
• Suaeda sect. Schoberia – 9 C₄ species^[10]
• Tecticornia – (Salicornioideae) 2 C₄ species^[17]
• Tidestromia (Gomphrenoideae) – 8 C₄ species^[11]

Asteraceae

The composite family Asteraceae contains three C₄ lineages, in two different tribes of subfamily Asteroideae.^[1][18] They include the model genus Flaveria with closely related C₃, C₄, and intermediate species.^[1]

• Flaveria (Tageteae) – 7 C₄ species, 2–3 origins (also includes C₃ and intermediate)^[1][19][20]
• Coreopsideae – 41 C₄ species^[18]
• Pectis (Tageteae) – 90 C₄ species^[21]

Boraginaceae

The borage family Boraginaceae contains one widespread C₄ genus, Euploca, which has also been treated as part of a distinct family Heliotropiaceae.^[22]

• Euploca (also includes C₃–C₄ intermediates^[23]) – 130 C₄ species, 1–3 origins^[1]

Cleomaceae

The Cleomaceae, formerly included in the caper family Capparaceae, contains three C₄ species in genus Cleome. These three species independently acquired the C₄ pathway; the genus also contains numerous C₃ as well as C₃–C₄ intermediate species.^[1][24][25]

• Cleome angustifolia
• C. gynandra
• C. oxalidea

Caryophyllaceae

In the carnation family Caryophyllaceae, the C₄ pathway evolved once, in a clade within the polyphyletic genus Polycarpaea.^[1][26]

• Polycarpaea – 20 C₄ species

Cyperaceae

The sedge family Cyperaceae is second only to the grasses in number of C₄ species. Prominent C₄ sedges include culturally important species such as papyrus (Cyperus papyrus) and chufa (C. esculentus) but also purple nutsedge (C. rotundus), one of the world's major weeds. Eleocharis vivipara uses C₃ carbon fixation in underwater leaves and C₄ carbon fixation in aerial leaves.^[1]

• Bulbostylis – 211 C₄ species
• Cyperus – 757 C₄ species
• Eleocharis ser. Tenuissimae – 10 C₄ species
• Eleocharis vivipara
• Fimbristylis – 303 C₄ species
• Rhynchospora – 40 C₄ species

Euphorbiaceae

The spurge family Euphorbiaceae contains the largest single C₄ lineage among eudicots. The C₄ spurges are diverse and widespread; they range from weedy herbs to the only known C₄ trees – four species from Hawaii, including Euphorbia olowaluana (up to 10 m) and E. herbstii (up to 8 m).^[1][6]

• Euphorbia subgenus Chamaesyce section Anisophyllum (also treated as genus Chamaesyce) – 350 C₄ species (also including C₃ and C₃–C₄ intermediate species)

Gisekiaceae

Contains a C₄ genus with a single species.

• Gisekia pharnaceoides^[27]

Hydrocharitaceae

Includes the only known aquatic C₄ plants.^[1]

• Egeria densa
• Hydrilla verticillata

Molluginaceae

The two C₄ species within the same genus have acquired the pathway independently.

• Mollugo – 2 C₄ species, 2 origins

Nyctaginaceae

• Allionia – 2 C₄ species
• Boerhavia – 42 C₄ species

Polygonaceae

• Calligonum – 80 C₄ species

Portulacaceae

The single genus of this family forms one C₄ lineage.

• Portulaca – 100 C₄ species, 1–2 origins

Poaceae

The grass family includes most of the known C₄ species – around 5000. They are only found in subfamilies of the

• Aristida – 288 C₄ species
• Stipagrostis – 56 C₄ species
• Chloridoideae (without Centropodieae) – 1596 C₄ species
• Centropodia – 4 C₄ species
• Eriachne – 50 C₄ species
• Tristachyideae – 87 C₄ species
• Andropogoneae – 1228 C₄ species (incl. maize, sugarcane, sorghum)
• Reynaudia filiformis
• Axonopus – 90 C₄ species
• Paspalum – 379 C₄ species
• Anthaenantia – 4 C₄ species
• Arthropoginae/Mesosetum clade – 35 C₄ species, 1–2 origins
• Arthropoginae/Onchorachis clade – 2 C₄ species
• Arthropoginae/Colaeteania clade – 7 C₄ species, 1–2 origins
• Anthephorinae – 286 C₄ species
• Echinochloa – 35 C₄ species
• Neurachne–Paraneurachne – 2 C₄ species, 2 origins
• Melinidinae–Panicinae–Cenchrinae – 889 C₄ species
• Alloteropsis – 5 C₄ species, 1–2 origins (incl. C₃ and intermediate)

Scrophulariaceae

• Anticharis – 4 C₄ species

Zygophyllaceae

• Tribuloideae – 37 C₄ species, 1–2 origins
• Tetraena simplex

References