Prenanthella
Prenanthella | |
---|---|
Scientific classification | |
Kingdom: | Plantae |
(unranked): | Angiosperms |
(unranked): | Eudicots |
(unranked): | Asterids |
Order: | Asterales |
Family: | Asteraceae |
Genus: | Prenanthella Rydb. |
Species: | P. exigua |
Binomial name | |
Prenanthella exigua (A.Gray) Rydb. | |
Synonyms | |
Lygodesmia exigua |
Prenanthella is a monotypic genus[1] of flowering plants in the daisy family containing the single species Prenanthella exigua, which is known by the common name brightwhite. It is native to the southwestern United States from California to Texas and it is known as far north as Idaho. Its habitat includes desert and woodlands. This annual herb produces a slender, branching stem reaching a maximum height near 40 centimeters. It has a sparse coating of glandular hairs and contains a milky juice. Most of the leaves are located near the base of the stem. They are widely lance-shaped and sometimes divided into segments. Smaller leaves occur higher on the stem; these may be reduced to scale-like structures, leaving the stem mostly bare. The inflorescence is a wide open panicle of several flower heads. Each small head is cylindrical and narrow, its base wrapped in lance-shaped phyllaries. At the tip of the head bloom 3 or 4 flowers, which are ray florets; there are no disc florets. Each floret has is white to pale pink and has a toothed tip. The fruit is a white achene with a pappus of white bristles.
References
- ↑ Ford, V. S., et al. (2006). Species divergence and relationships in Stephanomeria (Compositae): PgiC phylogeny compared to prior biosystematic studies. American Journal of Botany 93: 480-90.