Ephedra (plant)


Ephedra is a genus of gymnosperm shrubs., 74 species, and two hybrids, are accepted. The species of Ephedra are widespread in many arid regions of the world, ranging across southwestern North America, southern Europe, northern Africa, southwest and central Asia, northern China, and western South America. It is the only extant genus in its family, Ephedraceae, and order, Ephedrales, and one of the three extant genera of the division Gnetophyta together with Gnetum and Welwitschia.
In temperate climates, most Ephedra species grow on shores or in sandy soils with direct sun exposure. Common names in English include joint-pine, jointfir, Mormon-tea, or Brigham tea. The Chinese name for Ephedra species is mahuang. Ephedra is the origin of the name of the stimulant ephedrine, which the plants contain in significant concentration.

Description

The family Ephedraceae, of which Ephedra is the only extant genus, are gymnosperms, and generally shrubs, sometimes clambering vines, and rarely, small trees. Members of the genus frequently spread by the use of rhizomes.
The stems are green and photosynthetic. The leaves are opposite or whorled. The typical scalelike leaves are fused into a sheath at the base and is often shed soon after development. There are no resin canals. Most species have rudimentary leaves without chlorophyll or photosynthesis, but a few, like E. altissima, develop normal, slender leaf-like leaves up to long and also as adults.
The plants are mostly dioecious, with the pollen strobili in whorls of 1–10, each consisting of a series of decussate bracts. The pollen is furrowed. The female strobili also occur in whorls, with bracts which fuse around a single ovule. Fleshy bracts are white or red. There are generally 1–2 yellow to dark brown seeds per strobilus.

Taxonomy

The genus Ephedra was first described in 1753 by Carl Linnaeus. The type species is E. distachya. The family, Ephedraceae, was first described in 1829 by Barthélemy Charles Joseph Dumortier.

Evolutionary history

The oldest known members of the genus are from the Early Cretaceous around 125 million years ago, with records being known from the Aptian-Albian of Argentina, China, Portugal and the United States. The fossil record of Ephedra outside of pollen disappears after the Early Cretaceous. Molecular clock estimates have suggested that last common ancestor of living Ephedra species lived much more recently, during the Early Oligocene around 30 million years ago. However, pollen modified from the ancestral condition of the genus with branched pseudosulci, which evolved in parallel in the living North American and Asian lineages is known from the Late Cretaceous, suggesting that the last common ancestor is at least this old.

Species

, Plants of the World Online accepts the following 74 species, and two hybrids:
  • Ephedra alata Decne. – North Africa, Arabian Peninsula
  • Ephedra altissima Desf. non-Bové, non-Delile, non-Buch – high-climbing jointfir – North Africa, Canary Islands
  • Ephedra americana Humb. & Bonpl. ex Willd. – Bolivia, Ecuador, Peru, Argentina, Chile
  • Ephedra antisyphilitica Berland ex C.A.Mey. – clapweed, erect ephedra – Texas, Oklahoma, New Mexico, Nuevo León, Coahuila, Chihuahua
  • Ephedra aphylla Forssk. – eastern Mediterranean from Libya and Cyprus to the Persian Gulf
  • Ephedra × arenicola H.C.Cutler – Arizona, Utah
  • Ephedra aspera Engelm. ex S.Watson – boundary ephedra, pitamoreal – Texas, New Mexico, Arizona, Utah, Nevada, California, Chihuahua, Durango, Zacatecas, Sinaloa, Sonora, Baja California
  • Ephedra aurantiaca Takht. & Pachom. – Caucasus, Kazakhstan, Turkmenistan
  • Ephedra aurea Brullo et al.
  • Ephedra boelckei F.A.Roig – Argentina
  • Ephedra botschantzevii Pachom. – Kazakhstan, Tuva region of Siberia
  • Ephedra breana Phil. – frutilla de campo – Peru, Bolivia, Chile, Argentina
  • Ephedra brevifoliata Ghahr. – Iran
  • Ephedra californica S.Watson – California ephedra, California jointfir – California, western Arizona, Baja California
  • Ephedra chengiae Yang & Ferguson
  • Ephedra chilensis C.Presl – pingo-pingo - Chile, Argentina
  • Ephedra ciliata Fisch. & C.A.Mey. – North Africa, Middle East, India
  • Ephedra compacta Rose – widespread in much of Mexico
  • Ephedra coryi E.L.Reed – Cory's ephedra – Texas, New Mexico
  • Ephedra cutleri Peebles – Navajo ephedra, Cutler's ephedra, Cutler Mormon-tea, Cutler's jointfir – Colorado, Utah, Arizona, New Mexico, Wyoming
  • Ephedra dahurica Turcz. – Siberia, Mongolia
  • Ephedra dawuensis Y.Yang – Sichuan
  • Ephedra distachya L. – joint-pine, jointfir – southern Europe and central Asia from Portugal to Kazakhstan
  • Ephedra × eleutherolepis V.A.Nikitin – Tajikistan
  • Ephedra equisetina Bunge – ma huang – Caucasus, Central Asia, Siberia, Mongolia, Gansu, Hebei, Inner Mongolia, Ningxia, Qinghai, Shanxi, Xinjiang
  • Ephedra fasciculata A.Nelson – Arizona ephedra, Arizona jointfir, desert Mormon-tea – Arizona, California, Nevada, Utah
  • Ephedra fedtschenkoae Paulsen – Central Asia, Siberia, Mongolia, Xinjiang
  • Ephedra foeminea Forssk. – North Africa, Somalia, Balkans, Italy, Middle East; naturalized in Santa Barbara County of California
  • Ephedra fragilis Desf. – joint pine – Mediterranean, Canary Islands, Madeira
  • Ephedra frustillata Miers – Patagonian ephedra – Chile, Argentina
  • Ephedra funerea Coville & C.V.Morton – Death Valley ephedra, Death Valley jointfir – California, Arizona, Nevada
  • Ephedra gerardiana Wall. ex Klotzsch & Garcke – Gerard's jointfir, shan ling ma huang – Himalayas, Tibet, Yunnan, Siberia, Central Asia
  • Ephedra glauca Regel – Iran east to Mongolia and northern China
  • Ephedra gracilis Phil. ex Stapf
  • Ephedra holoptera Riedl – Iran
  • Ephedra intermedia Schrenk & C.A.Mey. – zhong ma huang – China, Siberia, Central Asia, Himalayas, Iran, Pakistan
  • Ephedra kardangensis P.Sharma & P.L.Uniyal – western Himalayas
  • Ephedra karumanchiana S.K.Patel, S.M.Patil, Raole & K.S.Rajput – Northwest India
  • Ephedra laristanica Assadi – Iran
  • Ephedra likiangensis Florin – Guizhou, Sichuan, Tibet, Yunnan
  • Ephedra lomatolepis Schrenk – Kazakhstan, Tuva region of Siberia
  • Ephedra milleri Freitag & Maier-St. – Oman, Yemen
  • Ephedra minuta Florin – Qinghai, Sichuan
  • Ephedra monosperma J.G.Gmel. ex C.A.Mey. – dan zi ma huang – Siberia, Mongolia, much of China including Tibet and Xinjiang
  • Ephedra multiflora Phil. ex Stapf – Chile, Argentina
  • Ephedra nebrodensis Tineo - Mediterranean region except northeast Africa
  • Ephedra nevadensis S.Watson – Nevada ephedra, Nevada jointfir, Nevada Mormon-tea – Baja California, California, Arizona, Nevada, Utah, Oregon
  • Ephedra nutans Miau & Xiao L.Pan – Xinjiang
  • Ephedra ochreata Miers – Argentina
  • Ephedra oxyphylla Riedl – Afghanistan
  • Ephedra pachyclada Boiss. – Middle East from Sinai and Yemen to Pakistan
  • Ephedra pedunculata Engelm. ex S.Watson – vine ephedra, vine jointfir – Texas, Chihuahua, Coahuila, Durango, San Luis Potosí, Nuevo León, Zacatecas
  • Ephedra pentandra Pachom. – Iran
  • Ephedra procera Fisch. & C.A.Mey. − Iran, Caucasus
  • Ephedra przewalskii Stapf – Central Asia, Mongolia, Pakistan, Gansu, Inner Mongolia, Ningxia, Qinghai, Tibet
  • Ephedra pseudodistachya Pachom. – Siberia, Mongolia
  • Ephedra regeliana Florin – xi zi ma huang – Central Asia, Siberia, Pakistan, Xinjiang
  • Ephedra rhytidosperma Pachom., syn. E. lepidosperma C.Y.Cheng – Gansu, Inner Mongolia, Ningxia, Mongolia
  • Ephedra rituensis Y.Yang, D.Z.Fu & G.H.Zhu – Qinghai, Xinjiang, Tibet
  • Ephedra rupestris Benth. – Ecuador, Peru, Bolivia, Argentina
  • Ephedra sarcocarpa Aitch. & Hemsl. – Pakistan, Afghanistan
  • Ephedra saxatilis Royle ex Florin
  • Ephedra sinica Stapf – cao ma huang, Chinese ephedra – Mongolia, Siberia, Primorye, Manchuria
  • Ephedra somalensis Freitag & Maier-St. – Somalia, Eritrea
  • Ephedra stipitata Biswas & Rita Singh
  • Ephedra strobilacea Bunge – Iran, Central Asia
  • Ephedra strongylensis Brullo et al.
  • Ephedra tilhoana Maire – Chad
  • Ephedra torreyana S.Watson – Torrey's ephedra, Torrey's jointfir, Torrey's Mormon-tea, cañutillo – Nevada, Utah, Colorado, Arizona, New Mexico, Texas, Chihuahua
  • Ephedra transitoria Riedl – Iraq, Syria, Palestine, Saudi Arabia
  • Ephedra triandra Tul. − Bolivia, Argentina
  • Ephedra trifurca Torrey ex S.Watson – longleaf ephedra, longleaf jointfir, longleaf Mormon-tea, popotilla, teposote – California, Arizona, New Mexico, Texas, Chihuahua, Sonora, Baja California
  • Ephedra trifurcata Zöllner
  • Ephedra tweedieana C.A.Mey. – Brazil, Argentina, Uruguay
  • Ephedra viridis Coville – green ephedra, green Mormon-tea – California, Nevada, Utah, Arizona, New Mexico, Colorado, Wyoming, South Dakota, Oregon
  • Ephedra vvedenskyi Pachom. – Iran, Caucasus, Turkmenistan

    Distribution

The genus is found in dry and desert regions worldwide, except for Australia.

Ecology

Ephedraceae are adapted to extremely arid regions, growing often in high sunny habitats, and occur as high as above sea level in both the Andes and the Himalayas. They make up a significant part of the North American Great Basin sage brush ecosystem.
Today, Ephedra plants are found no further south than 3°N in the Saharo-Arabian region. However, researchers have discovered evidence of this drought-resistant plant living over further south at Oldupai Gorge around one million years ago, based on fossil pollen, preserved tap roots, and supporting indicators of arid conditions.