Sisyrinchium

Not to be confused with Sisyrinchium Mill., illegitimate homonym, a synonym of Moraea

Sisyrinchium is a large genus of annual to perennial flowering plants in the family Iridaceae. Native to the New World, the species are known as blue-eyed grasses. Although they are not true grasses (Poaceae), they are monocots.

Sisyrinchium
Sisyrinchium bermudiana L. (type species)
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Monocots
Order:	Asparagales
Family:	Iridaceae
Subfamily:	Iridoideae
Tribe:	Sisyrinchieae
Genus:	Sisyrinchium L.
Species
Main article: List of Sisyrinchium species
Synonyms
Bermudiana Mill. Hydastylus Dryand. ex Salisb. Souza Vell. Paneguia Raf. Pogadelpha Raf. Echthronema Herb. Eriphilema Herb. Glumosia Herb. Oreolirion E.P.Bicknell

Several species in the eastern United States are threatened or endangered. This may be due to niche species emerging from their unique tendency toward rapid speciation which helps them adapt to specialized arenic habitats.

Description

Sisyrinchium angustifolium

Sisyrinchium californicum

Sisyrinchium albidum

These are not true grasses, but many species have the general appearance of grasses, as they are low-growing plants with long, thin leaves. They often grow on grasslands. Many species resemble irises, to which they are more closely related. Most species grow as perennial plants, from a rhizome, though some are short-lived (e.g. Sisyrinchium striatum), and some are annuals (e.g. Sisyrinchium iridifolium).

The flowers are relatively simple and often grow in clusters.

Many species, particularly the South American ones, are not blue, despite the common name. The genus includes species with blue, white, yellow, and purple petals, often with a contrasting centre. Of the species in the United States, the Western Blue-eyed Grass (Sisyrinchium bellum) is sometimes found with white flowers, while the California Golden-eyed Grass (Sisyrinchium californicum) has yellow flowers.

Taxonomy

The genus was named by Carl Linnaeus in 1753, based on the species Sisyrinchium bermudiana (commonly called Bermudiana). The taxonomy of this genus is rather perplexing and confusing, as several of these species, such as Sisyrinchium angustifolium, form complexes with many variants named as species. More genetic research and cladistic analysis need to be performed to sort out the relationships between the species. Some species, notably Sisyrinchium douglasii, have been transferred to the separate genus Olsynium.

The greatest diversity for the genus is found in South America.

Approximately one third of the species in the genus have oil producing hairs called elaiophores to attract oil-bees. Nearly all these species are native to South America.

Etymology

Sisyrinchíon is the Greek word, recorded by Pliny and Theophrastus, for the Barbary nut iris (Iris or Moraea sisyrinchium), and refers to the way the corm tunics resemble a shaggy goat's-hair coat, sisýra. Authors as early as 1666 give the dubious etymology of Latin sūs "pig" and Greek rhynchos "nose", referring to pigs grubbing the roots. As Goldblatt and Manning explain, "the reason for applying the name to a genus of New World Iridaceae was apparently arbitrary."

Selected species

Main article: List of Sisyrinchium species

There are up to 200 species, including:

Sisyrinchium albidum Raf. Sisyrinchium angustifolium Mill. – narrow-leaf blue-eyed-grass Sisyrinchium atlanticum E.P.Bicknel - eastern blue-eyed grass Sisyrinchium bellum S.Watson – western blue-eyed grass or Californian blue-eyed grass Sisyrinchium bermudiana – bermudiana Sisyrinchium californicum – golden blue-eyed grass, yellow-eyed-grass, and golden-eyed-grass Sisyrinchium campestre Bickn. Sisyrinchium dichotomum – wishbone blue-eyed grass, white irisette, and reflexed blue-eyed grass Sisyrinchium elmeri – Elmer's blue-eyed grass Sisyrinchium funereum – Funeral Mountain blue-eyed grass and Death Valley blue-eyed-grass Sisyrinchium groenlandicum - Greenland blue-eyed grass Sisyrinchium halophilum – Nevada blue-eyed grass Sisyrinchium idahoense Bickn. – Idaho blue-eyed grass Sisyrinchium longipes – timberland blue-eyed grass Sisyrinchium micranthum – annual blue-eyed grass, blue pigroot, fairy stars, and striped rush-leaf Sisyrinchium montanum Greene – strict blue-eyed grass, American blue-eyed-grass Sisyrinchium platense I.M.Johnst Sisyrinchium pruinosum – spotted blue-eyed grass or dotted blue-eyed grass Sisyrinchium sarmentosum – mountain blue-eyed grass and pale blue-eyed-grass Sisyrinchium septentrionale – northern blue-eyed grass Sisyrinchium striatum – pale yellow-eyed-grass or satin flower

Gallery

• 
  Prairie blue-eyed grass (Sisyrinchium campestre)
• 
  Strict blue-eyed grass (Sisyrinchium montanum var. montanum)
• 
  Needletip blue-eyed grass (Sisyrinchium mucronatum)
• 
  Coastalplain blue-eyed grass (Sisyrinchium fuscatum)

References

• Rudall, P. J., A. Y. Kenton, and T. J. Lawrence. 1986 - An anatomical and chromosomal investigation of Sisyrinchium and allied genera. Bot. Gaz. 147: 466–477 Ajilvsgi, Geyata. 1984 - Wildflowers of Texas. Library of Congress: 84-50025

External links

• Flora of North America
• Sections of the genus