Gomphrenoideae

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Ordo: Caryophyllales

Familia: Amaranthaceae s.l.
Cladus: Amaranthaceae s.str.
Subfamilia: Gomphrenoideae

Genera: Alternanthera – Blutaparon – Froelichia – Froelichiella – Gomphrena – Gossypianthus – Guilleminea – Hebanthe – Hebanthodes – Iresine – Lithophila – Pedersenia – Pfaffia – Pseudogomphrena – Pseudoplantago – Quaternella – Tidestromia – Xerosiphon

Names in synonymy: Irenella – Woehleria
Name

Gomphrenoideae Schinz, 1893

Type: Gomphrena L.

References
Primary references

Schinz, H. 1893. Amarantaceae. pp. 91–118. In: Engler, A. & Prantl, K. (eds.), Die natürlichen Pflanzenfamilien, III Teil, Abteilung 1a. Leipzig: Wilhelm Engelmann. BHL Reference page. : 97.

Additional references

Hernández-Ledesma, P., Berendsohn, W. G., Borsch, T., Mering, S. v., Akhani, H., Arias, S., Castañeda-Noa, I., Eggli, U., Eriksson, R., Flores-Olvera, H., Fuentes-Bazán, S., Kadereit, G., Klak, C., Korotkova, N., Nyffeler R., Ocampo G., Ochoterena, H., Oxelman, B., Rabeler, R. K., Sanchez, A., Schlumpberger, B. O. & Uotila, P. 2015. A taxonomic backbone for the global synthesis of species diversity in the angiosperm order Caryophyllales. Willdenowia 45(3): 281–383. DOI: 10.3372/wi.45.45301 Open access Reference page.
Sánchez del-Pino, I., Borsch, T & Motley, T.J. 2009. trnL-F and rpl16 Sequence Data and Dense Taxon Sampling Reveal Monophyly of Unilocular Anthered Gomphrenoideae (Amaranthaceae) and an Improved Picture of Their Internal Relationships. Systematic Botany 34(1): 57-67. DOI: 10.1600/036364409787602401 Reference page.
Borsch, T., Flores‐Olvera, H., Zumaya, S. & Müller, K. 2018. Pollen characters and DNA sequence data converge on a monophyletic genus Iresine (Amaranthaceae, Caryophyllales) and help to elucidate its species diversity. Taxon 67(5): 944–976. DOI: 10.12705/675.7 Reference page.

The Gomphrenoideae are a subfamily of the Amaranthaceae.

The stamens have anthers with only one lobe (locule) and two pollen sacs. Many species show C4-photosynthesis pathway.[1]

The center of diversity lies in Central America, Mexico and the dry forests and thorn bush savannas of South America.[2]

Systematics

The subfamily Gomphrenoideae was first published in 1893 by Hans Schinz (in: Engler und Prantl (Eds.): Die Natürlichen Pflanzenfamilien vol. 3, 1a, p. 97).

According to phylogenetic research by Sanchez Del-Pino (2009), the subfamily Gomphrenoideae Schinz is regarded as a monophyletic taxon with 19 genera and about 300-400 species. The traditional classification with two tribes (Gomphreneae and Pseudoplantageae) does not reflect the phylogenetic relationship in this group. Three clades can be recognized.:[1]
Iresinoids

Irenella Suess., with only one species:
Irenella chrysotricha Suess., in rain forests of Ecuador. Phylogenetically, it falls within Iresine.
Iresine P.Browne (Syn.: Dicraurus Hook. f.): with about 45 species in North and South America.
Woehleria Griseb.: with only one species
Woehleria serpyllifolia Griseb., on mountain coasts of Cuba. Phylogenetically, it falls within Iresine.

This is the sister clade of the two other clades.
Alternantheroids

Alternanthera Forssk. (Syn.: Brandesia Mart.): with about 100-200 species, mainly in America, also in Africa and Australia.
Pedersenia Holub: with about 10 species in tropical America.
Tidestromia Standl.: with about 6 species in deserts of southern North America.

C4 carbon fixation evolved independently in the genera Alternathera, which also contains C3 and C3–C4 intermediate species, and Tidestromia.[3][4]
Gomphrenoids

Blutaparon Raf. (Syn.: Philoxerus R.Br.): with about 5 species at shores of North and Middle America, West Africa, Micronesia and Japan, for example:
Blutaparon rigidum
Froelichia Moench: with about 12 species in America.
Froelichiella R.E.Fr., with only one species:
Froelichiella grisea R.E.Fr. in Brasília.
Gomphrena L. (Syn.: Bragantia Vand.): with about 90 species in America and about 30 species in Australia. This genus is polyphyletic, so taxonomical changes have to be expected.[1]
Gomphrena pulchella
Gomphrena decumbens
Gomphrena globosa
Gossypianthus Hook.: with 2 species in southern North America.
Guilleminea Kunth (Syn.: Brayulinea Small)
Hebanthe Mart.: with about 7 species in tropical America.
Hebanthodes Pedersen, with only one species:
Hebanthodes peruviana Pedersen in Peru.
Lithophila Sw., with 2 species on Galapagos and the Caribic
Pfaffia Mart.: with about 35 species in tropical America.
Pseudogomphrena R.E.Fr.,with only one species:
Pseudogomphrena scandens R.E.Fr. in Brasília.
Pseudoplantago Suess.: with one species in Venezuela and one in Argentina.
Quaternella Pedersen: with 3 species in Brasília.
Xerosiphon Turcz.: with about 2 species in Brasília.

One large clade within this group, containing the genera Froelichia, Guilleminea, Blutaparon, some Gomphrena species, and probably Gossypianthus and Lithophila, has acquired the C4 carbon fixation pathway.[3][4] Some of these C4 species occur at unusually high altitudes in the Andes, in cooler conditions than their C3 relatives.[5]

References

Ivonne Sánchez del-Pino, Thomas Borsch & Timothy J. Motley (2009): trnL-F and rpl16 Sequence Data and Dense Taxon Sampling Reveal Monophyly of Unilocular Anthered Gomphrenoideae (Amaranthaceae) and an Improved Picture of Their Internal Relationships, In: Systematic Botany, Volume 34 (1), p. 57-67. doi:10.1600/036364409787602401
Kai Müller & Thomas Borsch (2005): Phylogenetics of Amaranthaceae using matK/trnK sequence data – evidence from parsimony, likelihood and Bayesian approaches, In: Annals of the Missouri Botanical Garden, 92, p. 66-102.
Sage, R.F. (2016). "A portrait of the C4 photosynthetic family on the 50th anniversary of its discovery: species number, evolutionary lineages, and Hall of Fame". Journal of Experimental Botany. 67 (14): 4039–4056. doi:10.1093/jxb/erw156. ISSN 0022-0957. PMID 27053721. open access
Sage, R.F.; Sage, T.L.; Pearcy, R.W.; Borsch, T. (2007). "The taxonomic distribution of C4 photosynthesis in Amaranthaceae sensu stricto". American Journal of Botany. 94 (12): 1992–2003. doi:10.3732/ajb.94.12.1992. ISSN 0002-9122. PMID 21636394. open access
Bena, M.J.; Acosta, J.M.; Aagesen, Lone (2017). "Macroclimatic niche limits and the evolution of C4 photosynthesis in Gomphrenoideae (Amaranthaceae)". Botanical Journal of the Linnean Society. 184 (3): 283–297. doi:10.1093/botlinnean/box031. ISSN 0024-4074.