Purshia
Purshia | |
---|---|
Purshia stansburyana | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Rosids |
Order: | Rosales |
Family: | Rosaceae |
Subfamily: | Dryadoideae |
Genus: | Purshia DC. ex Poir. |
Type species | |
Purshia tridentata | |
Range | |
Synonyms | |
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Purshia (bitterbrush or cliff-rose) is a small genus of 5–8 species of flowering plants in the family Rosaceae which are native to western North America.
Description
[edit]Purshia species form deciduous or evergreen shrubs, typically reaching 0.3–5 metres (1–16+1⁄2 feet) tall. The leaves are 1–3 centimetres (1⁄2–1+1⁄4 inches) long, deeply three- to five-lobed, with revolute margins. The flowers are 1–2 cm in diameter, with five white to pale yellow or pink petals and yellow stamens. The fruit is a cluster of dry, slender, leathery achenes which are 2–6 cm long. The roots have nodules that host nitrogen-fixing Frankia bacterium.[1]
Taxonomy
[edit]Taxonomic history
[edit]The genus was originally placed in the subfamily Rosoideae.[2] In the past, the evergreen species were treated separately in the genus Cowania; this genus is still accepted by some botanists.
Modern classification
[edit]The classification of Purshia within the family Rosaceae has been unclear.[3][4] It is now placed in the subfamily Dryadoideae.[2]
Species
[edit]Purshia comprises the following species:[5][6]
- Purshia ericifolia (Torr. ex A.Gray) Henr. – Heath cliffrose (Texas)
- Purshia glandulosa Curran – Desert bitterbrush (Nevada, Utah, Arizona)
- Purshia mexicana (D.Don) Henr. – Mexican cliffrose (Mexico, Arizona)
- Purshia pinkavae Schaack – Pinkava's cliffrose (Arizona)
- Purshia plicata (D.Don) Henrard (syn. Cowania plicata) – Antelope bush (Nuevo León, Mexico).
- Purshia stansburyana (Torr.) Henr. – Stansbury cliffrose (Idaho south to California, Arizona and New Mexico)
- Purshia tridentata (Pursh) DC. – Antelope bitterbrush (British Columbia south to California and New Mexico)
Hybrids
[edit]The following hybrid has been described:[5]
- Purshia × subintegra (Kearney) Henr. (P. pinkavae × P. stansburyana) – (Arizona)
Species names with uncertain taxonomic status
[edit]The status of the following species and hybrids is unresolved:[5]
- Purshia ciliata Dennst.
- Purshia mollis Lehm.
- Purshia plicata (D.Don) Henr.
- Purshia subintegra (Kearney) Henrickson
Distribution and habitat
[edit]The genus is native to western North America, where the species grow in dry climates from southeast British Columbia, Canada, south throughout the western United States to northern Mexico.
Gallery
[edit]- P. tridentata, Lava Beds National Monument
- P. stansburiana, Red Rock Canyon, Nevada
- P. stansburiana, Red Rock Canyon, Nevada
References
[edit]- ^ Swensen, S.M.; Mullin, B.C. (1997). "The impact of molecular systematics on hypotheses for the evolution of root nodule symbioses and implications for expanding symbioses to new host plant genera". Plant and Soil. 194 (1–2): 185–192. doi:10.1023/A:1004240004063.
- ^ a b Potter, D.; Eriksson, T.; Evans, R.C.; Oh, S.; Smedmark, J.E.E.; Morgan, D.R.; Kerr, M.; Robertson, K.R.; Arsenault, M.; Dickinson, T.A.; Campbell, C.S. (2007). "Phylogeny and classification of Rosaceae". Plant Systematics and Evolution. 266 (1–2): 5–43. Bibcode:2007PSyEv.266....5P. doi:10.1007/s00606-007-0539-9.
- ^ Morgan, D.R.; Soltis, D.E.; Robertson, K.R. (1994). "Systematic and evolutionary implications of rbcL sequence variation in Rosaceae". American Journal of Botany. 81 (7): 890–903. doi:10.1002/j.1537-2197.1994.tb15570.x. JSTOR 2445770.
- ^ Eriksson, T.; Hibbs, M.S.; Yoder, A.D.; Delwiche, C.F.; Donoghue, M.J. (2003). "The phylogeny of Rosoideae (Rosaceae) based on sequences of the internal transcribed spacers (ITS) of nuclear ribosomal DNA and the trnL/F region of chloroplast DNA". International Journal of Plant Sciences. 164 (2): 197–211. doi:10.1086/346163.
- ^ a b c "The Plant List entry for Purshia". The Plant List, v.1.1. Royal Botanic Gardens, Kew and the Missouri Botanical Garden. September 2013. Retrieved 15 December 2020.
- ^ Govaerts R. "Purshia DC. ex Poir". Plants of the World Online. Board of Trustees of the Royal Botanic Gardens, Kew. Retrieved 15 December 2020.
External links
[edit]- Media related to Purshia at Wikimedia Commons
- Jepson Flora Project: Purshia — (click 'taxon' to see treatments of California native species)