Lasthenia

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Goldfields

Goldfields (Lasthenia glabrata)

Scientific classification

Kingdom:	Plantae
Division:	Magnoliophyta
Class:	Magnoliopsida
Order:	Asterales
Family:	Asteraceae
Genus:	Lasthenia Cass.

Species

See text.

Lasthenia, commonly known as goldfields, is a genus of the botanical family Asteraceae. Etymology of the genus derives from the Ancient Greek word Lasthenia who was a female pupil of Plato who dressed as a man.

1 Morphology
2 Species
3 Line note references
4 General reference

[edit] Morphology

The goldfield genus comprises annual, rarely perennial herbs, that manifest as either glabrous or hairy. Stems are typcially branched and erect, attaining a height of less than 60 centimeters. Their opposite leaves, of length of up to 20 centimeters are entire to pinnate. Inflorescences are characterized by solitary heads (sometimes in cymes), with phyllaries free or partly fused. The receptacle may present as naked and narrowly conic to hemispheric. The normally yellow ray flowers may number four to 21, and the ligules are typically yellow as well. The disk flowers are numerous and generally yellow corollae are typically five-lobed; anther tips manifest as acuminate to triangular, while style tips may be triangular or round, but typically hair-tufted. Fruits are less than five millimeters across, cylindric to obovoid in shape, and black or gray in color. The pappus may present awns or scales, or infrequently neither. The genus is mostly cross-pollinated.^[1]

[edit] Species

There are a total of eighteen species, seventeen are endemic to North America and one is only found in Chile. Of the seventeen species found in North America, most are endemic to California.

Lasthenia burkei, Burke's goldfields, an endangered species
Lasthenia californica, California goldfields, found in northern California, Oregon, and Baja California
Lasthenia chrysantha, akali-sink goldfields, endemic to California
Lasthenia conjugens, Contra Costa goldfields, an endangered species
Lasthenia coronaria, crowned/royal goldfields, found in California and northern Mexico
Lasthenia debilis, Contra Costa goldfields, endemic to California
Lasthenia ferrisiae, Ferris's goldfields, endemic to California
Lasthenia fremontii, Fremont's goldfields, endemic to California
Lasthenia glaberrima, smooth goldfields, found in California, Oregon, Washington, and British Columbia
Lasthenia glabrata, yellow-ray goldfields, endemic to California
Lasthenia gracilis, common goldfields, found in California, Arizona, the Channel Islands of California, and northern Mexico
Lasthenia kunthii, Chilean goldfields, found in vernal pools in Chile
Lasthenia leptalea, Salinas Valley goldfields, endemic to California
Lasthenia maritima, maritime/seaside goldfields, found along the coast and offshore islands/rocks from California to British Columbia
Lasthenia microglossa, Small-ray goldfields, endemic to California
Lasthenia minor, coastal goldfields, endemic to coastal and inland California
Lasthenia ornduffii, Ornduff's goldfields, an endangered species, endemic to Oregon
Lasthenia platycarpha, akali goldfields, commonly in California