''Psorothamnus'' is a genus of plants in the legume family. These are shrubs and small trees. Many are known by the general common name indigo bush. Some are referred to as daleas, as this genus was once included in genus ''

Dalea ''Dalea'' is a genus of flowering plants in the legume family, Fabaceae. Members of the genus are commonly known as prairie clover or indigo bush. Its name honors English apothecary Samuel Dale (1659–1739). They are native to the Western hem ...

''. These are generally thorny, thickly branched, strongly scented bushes. Most species bear

lupin ''Lupinus'', commonly known as lupin, lupine, or regionally bluebonnet etc., is a genus of plants in the legume family Fabaceae. The genus includes over 199 species, with centers of diversity in North and South America. Smaller centers occur ...

like raceme inflorescences of bright purple legume flowers and gland-rich pods. ''Psorothamnus'' species are native to the

southwestern United States The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that generally includes Arizona, New Mexico, and adjacent portions of California, Colorado, Ne ...

and northern

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. The genus is

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

and it has been proposed that the genus ''Psorodendron'' be reinstated to accommodate sections ''Xylodalea'', ''Capnodendron'', and ''Winnemucca''.

Species

''Psorothamnus'' comprises the following species: * ''

Psorothamnus arborescens ''Psorothamnus arborescens'' is a species of flowering plant in the legume family known by the common name Mojave indigo bush. Distribution ''Psorothamnus arborescens'' is native to southwestern North America, where it can be found in many type ...

'' (A. Gray) Barneby—Mojave indigo bush ** var. ''arborescens'' (A. Gray) Barneby ** var. ''minutifolius'' (Parish) Barneby ** var. ''pubescens'' (Parish) Barneby ** var. ''simplicifolius'' (Parish) Barneby * ''

Psorothamnus emoryi ''Psorothamnus emoryi'', common names dyebush, white dalea, or Emory's indigo bush, is a perennial legume shrub or subshrub common to the desert mesas of the southern part of the U.S. states of Arizona and California, and regions of the Mexican ...

'' (A. Gray) Rydb.—dyebush, Emory's indigo bush * ''

Psorothamnus fremontii ''Psorothamnus fremontii'', the Fremont's dalea or Fremont's indigo bush (after John C. Frémont) is a perennial legume shrub. Distribution ''Psorothamnus fremontii'' is common to the Southwestern United States and northwest Mexico - in the stat ...

'' (A. Gray) Barneby—Fremont's indigo bush ** var. ''attenuatus'' Barneby ** var. ''fremontii'' (A. Gray) Barneby * ''

Psorothamnus kingii ''Psorothamnus'' is a genus of plants in the legume family. These are shrubs and small trees. Many are known by the general common name indigo bush. Some are referred to as daleas, as this genus was once included in genus '' Dalea''. These are g ...

'' (S. Watson) Barneby—King's dalea * ''

Psorothamnus nummularius ''Psorothamnus'' is a genus of plants in the legume family. These are shrubs and small trees. Many are known by the general common name indigo bush. Some are referred to as daleas, as this genus was once included in genus '' Dalea''. These are g ...

'' (M.E. Jones) S.L. Welsh * ''

Psorothamnus polydenius ''Psorothamnus polydenius'' is a species of flowering plant in the legume family known by the common names Nevada dalea and Nevada indigobush. It is native to the deserts of the southwestern United States from the Mojave Desert in California to ...

'' (S. Watson) Rydb.—Nevada dalea * ''

Psorothamnus schottii ''Psorothamnus schottii'' is a species of flowering plant in the legume family known by the common name Schott's dalea. It is native to the Sonoran Deserts of northern Mexico and adjacent sections of Arizona and the Colorado Desert in California ...

'' (Torr.) Barneby—Schott's dalea * ''

Psorothamnus scoparius ''Psorothamnus scoparius'' is a thornless bush in the bean family (Fabaceae), native to North America. It is known as broom smokebush and broom dalea. Distribution and habitat ''Psorothamnus scoparius'' is native to the southwestern United State ...

'' (A. Gray) Rydb.—broom dalea * ''

Psorothamnus spinosus ''Psorothamnus spinosus'', or ''Delea spinosa'', is a perennial legume tree of the deserts in North America. Common names include smokethorn, smoketree, smoke tree, smokethorn dalea, and corona de Cristo. Distribution ''P. Spinosus'' is nati ...

'' (A. Gray) Barneby—smoketree, smokethorn * ''

Psorothamnus thompsoniae ''Psorothamnus'' is a genus of plants in the legume family. These are shrubs and small trees. Many are known by the general common name indigo bush. Some are referred to as daleas, as this genus was once included in genus '' Dalea''. These are g ...

'' (Vail) S.L. Welsh & N.D. Atwood—Thompson's dalea

References

External links

CalFlora Database: ''Psorothamnus''Jepson Manual eFlora (TJM2) treatment of ''Psorothamnus''USDA Plants Profile for ''Psorothamnus''
* * {{Taxonbar, from=Q5229140 Fabaceae genera Flora of the California desert regions Flora of the Great Basin Natural history of the Mojave Desert