Prenanthella

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Cladus: Asterids
Cladus: Campanulids
Ordo: Asterales

Familia: Asteraceae
Subfamilia: Cichorioideae
Tribus: Cichorieae
Subtribus: Microseridinae
Genus: Prenanthella
Species: P. exigua
Name

Prenanthella Rydb., Bull. Torrey Bot. Club 33: 160. (1906)

monotypic taxon

Note: Sometimes found synonymous with Lygodesmia (Hassler et al., 2018 c.f. Lee et al. 2003 & Tropicos, 2018)
References

Rydberg, P.A. 1906. Bulletin of the Torrey Botanical Club 33: 160.
Hassler, M. 2018. Prenanthella. World Plants: Synonymic Checklists of the Vascular Plants of the World In: Roskovh, Y., Abucay, L., Orrell, T., Nicolson, D., Bailly, N., Kirk, P., Bourgoin, T., DeWalt, R.E., Decock, W., De Wever, A., Nieukerken, E. van, Zarucchi, J. & Penev, L., eds. 2018. Species 2000 & ITIS Catalogue of Life. Published on the internet. Accessed: 2018 Nov. 17. Reference page.
International Plant Names Index. 2018. 17. Published online. Accessed: Nov. 2018.
Lee, J., Baldwin, B.G. & Gottlieb, L.D. 2003. Phylogenetic relationships among the primarily North American genera of Cichorieae (Compositae) based on analysis of 18S-26S nuclear rDNA ITS and ETS sequences. Systematic Botany 28(3): 616–626. JSTOR ResearchGate Reference page.
Tropicos.org 2018. Prenanthella. Missouri Botanical Garden. Published on the internet. Accessed: 2018 Nov. 17.

Prenanthella is a monotypic genus of flowering plants in the daisy family.[1] It contains the single species Prenanthella exigua, which is known by the common name brightwhite.[2] 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.
USDA Plants Profile