Chenopodioideae

The Chenopodioideae are annual or perennial herbs, subshrubs, shrub or small trees. The leaves are usually alternate and flat. The flowers are often unisexual. Many species are monoecious or have mixed inflorescences of bisexual and unisexual flowers. Some species are dioecious, like Spinacia, Grayia, Exomis microphylla, and Atriplex. In several species of tribe Atripliceae, the female flowers are without perianth, but enclosed by two bracts. The species with a perianth have up to five tepals. The seed is horizontal or vertical, with annular or horseshoe-shaped embryo. == Distribution ==

The subfamily Chenopodioideae is distributed worldwide, but originates from Eurasia. == Systematics ==

''), tribe Anserineae '', tribe Atripliceae '', tribe Atripliceae '', tribe Atripliceae '', tribe Axyrideae '', tribe Dysphanieae The genera of this subfamily were formerly classified in family Chenopodiaceae in the Cronquist system. According to Fuentes-Bazan et al. (2012) and based on molecular genetic research, the subfamily comprises four tribes and includes about twenty-six genera: • Tribus Anserineae Dumort. (Syn. Spinacieae), with two genera: • Spinacia L.: with three species in Western Asia and North Africa: • Spinach (Spinacia oleracea) • Blitum, with 12 species nearly worldwide, for example: • Blitum capitatum – Strawberry Blite (Syn. Chenopodium capitatum) • Blitum bonus-henricus – Good King Henry (Syn. Chenopodium bonus-henricus) • Blitum virgatum – leafy goosefoot (Syn. Chenopodium foliosum) • Tribus Atripliceae C. A. Mey. (Syn. Chenopodieae Dumort.): Fuentes-Bazan et al. (2012) include here also Chenopodium and related genera, as Chenopodiastrum, Lipandra and Oxybasis. • Archiatriplex G.L.Chu, with only one species: • Archiatriplex nanpinensis G.L.Chu: endemic in the Chinese province Sichuan. • Atriplex L. - saltbush, orache (Syn.: Blackiella, Cremnophyton, Haloxanthium, Neopreissia, Obione, Pachypharynx, Senniella, Theleophyton), with about 300 species worldwide • Baolia H.W.Kung & G.L.Chu, with only one species: • Baolia bracteata H.W.Kung & G.L.Chu, endemic in the Chinese province Gansu. • Chenopodiastrum S. Fuentes, Uotila & Borsch: with five species, for example: • Chenopodiastrum hybridum (L.) S. Fuentes, Uotila & Borsch (Syn. Chenopodium hybridum L.) • Chenopodiastrum murale (L.) S. Fuentes, Uotila & Borsch – Sowbane, nettle-leaf goosefoot (Syn. Chenopodium murale L.) • Chenopodiastrum simplex (Torrey) S.Fuentes, Uotila & Borsch – Maple-leaf goosefoot (Syn.: Chenopodium simplex (Torrey) Raf.) • Chenopodium L. – goosefoot (sensu stricto, incl. Einadia Raf. and Rhagodia R.Br. • Dysphania R.Br., with about 42 species worldwide, for example: • Dysphania ambrosioides – epazote • Dysphania anthelmintica – wormseed • Neomonolepis , with one species, Neomonolepis spathulata, from western North America. • Suckleya A.Gray, with only one species: • Suckleya suckleyana (Torr.) Rydb., a succulent annual from western North America. • Teloxys Moq.: with only one species: • Teloxys aristata (L.) Moq. (Syn.: Chenopodium aristatum L., Dysphania aristata): from Eastern Europe to temperate Asia, naturalized elsewhere. ==Fossil record==

The oldest fossil records for Chenopodioideae are pollen grains recovered from Maastrichtian sediments of the Edmonton Formation in Canada. ==References==