Grayia (plant)

Source: Wikipedia, the free encyclopedia.

Grayia
Grayia spinosa
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Order: Caryophyllales
Family: Amaranthaceae
Subfamily: Chenopodioideae
Tribe: Atripliceae
Genus: Grayia
Arn.
Synonyms[1]

Zuckia Standl.

Grayia is a genus of plants in the subfamily Chenopodioideae of the family Amaranthaceae. Common names are siltbush and hopsage. The four shrubby species occur in arid and semiarid regions of western North America:[2]

Description

The species of Grayia are

leaves of 6–80 × 1.5–42 mm are succulent or coriaceous. They are nearly sessile or basally tapering to short petioles. The green to grayish leaf blades can be elliptic, ovate, obovate, spatulate, or linear-oblanceolate, with entire margins and prominent midveins. Especially at the tips, the leaves are hairy with simple or branched hairs. The leaves have a "normal" (non-Kranz) anatomy.[1]

The plants are

bracteoles, a perianth is lacking, they consist just of an ovary with 2 filiform, exserted stigmas.[1]

In fruit, the bracteoles enclosing the fruit become accrescent, folded along the midribs and connate nearly to the apex, 4–14 × 3–15 mm. Their shape can be orbicular, broadly elliptic, or cordate, their margins are usually entire, but sometimes wavy or extended into two wings, their surface is flat or ribbed, glabrous or hairy. Initially, bracteoles are yellowish-greenish or cream-colored, later they become reddish or pinkish. The orbicular, obovoid or laterally compressed-lenticular fruit (utricle) does not fall at maturity. The membranous

perisperm.[1]

The flowering time is March to June.[1]

The chromosome numbers are 2n = 18 (for the diploid Grayia arizonica and Grayia brandegeei) and 2n = 36 (for the tetraploid Grayia spinosa and Grayia plummeri).[1]

Distribution

The genus Grayia is native in the western United States (

semiarid regions on heavy clay, sandy loams, on alkaline or scarcely alkaline soils. Although overlapping in ranges, the species differ in the preferred soils.[1]

Systematics

The genus Grayia has been first described by

George Arnott Walker-Arnott in 1840 in: The Botany of Captain Beechey's Voyage (p. 387–388).[3] It included just one species, Grayia polygaloides Hook. & Arn. (nom. illeg.) = Chenopodium spinosum Hook. = Grayia spinosa (Hook.) Moq. The genus name was given in honour to the American botanist Asa Gray.[4]

Grayia belongs to the tribe

phylogenetic
research, Zacharias & Baldwin (2010) included here the genus Zuckia. Now Grayia comprises 4 species:

  • Grayia arizonica (Standl.) E.H.Zacharias,[1] (Syn. Zuckia arizonica Standl., Zuckia brandegeei var. arizonica (Standl.) S. L. Welsh) - Arizona siltbush: in Arizona and Utah
  • Grayia brandegeei A. Gray[1] (Syn. Zuckia brandegeei (A. Gray) S. L. Welsh & Stutz) - Brandegee's siltbush: in Colorado, Arizona, Utah
  • Grayia plummeri (Stutz & S.C.Sand.) E.H.Zacharias,[1] (Syn. Grayia brandegeei var. plummeri Stutz & S. C. Sand., Zuckia brandegeei var. plummeri (Stutz & S. C. Sand.) Dorn) - Plummer's siltbush: in Colorado, Wyoming, New Mexico and Utah
  • Grayia spinosa (Hook.) Moq.,[1] spiny hopsage: in Colorado, Idaho, Montana, Oregon, Washington, Wyoming, Arizona, California, Nevada and Utah.

References

  1. ^
    doi:10.1600/036364410X539907
  2. ^ Grayia, Germplasm Resources Information Network - (GRIN) Online Database, accessdate 2013-07-10.
  3. ^ Grayia first description, scanned at BHL
  4. ^ Noel H. Holmgren: Grayia in Flora of North America

External links

Wikimedia Commons has media related to Grayia.
Wikispecies has information related to Grayia (Amaranthaceae).
Retrieved from "https://en.wikipedia.org/w/index.php?title=Grayia_(plant)&oldid=1219360345"