Erysimum capitatum var. purshii

(Durand) Rollins

Cruciferae Continental N. Amer., 482. 1993.

Basionym: Erysimum asperum var. purshii Durand Trans. Amer. Philos. Soc., n. s. 11: 159. 1859
Synonyms: Cheiranthus alpestris (Cockerell) A. Heller Cheiranthus argillosus Greene Cheiranthus aridus A. Nelson Cheiranthus asperrimus Greene Cheiranthus bakeri Greene Cheiranthus nivalis Greene Cheiranthus nivalis var. amoenus Greene Cheiranthus oblanceolatus (Rydberg) A. Heller Cheiranthus radicatus (Greene) Rydberg Cheirinia amoena (Greene) Rydberg Cheirinia argillosa (A. Nelson) Rydberg Cheirinia arida (Greene) Rydberg Cheirinia asperrima (Greene) Rydberg Cheirinia bakeri Rydberg Cheirinia brachycarpa (Daniels) Cockerell Cheirinia cockerelliana Wooton & Standley Cheirinia desertorum (Greene) Rydberg Cheirinia nivalis (Rydberg) Rydberg Cheirinia nivalis var. radicata (Rydberg) Cockerell Cheirinia oblanceolata (Greene) Rydberg Cheirinia radicata Rydberg Erysimum amoenum (Greene) Rydberg Erysimum angustatum (A. Nelson) A. Nelson Erysimum argillosum (Greene) Rydberg Erysimum aridum (Greene) Rydberg Erysimum asperrimum Daniels Erysimum asperum var. amoenum (Greene) Reveal Erysimum asperum var. angustatum (Rydberg) B. Boivin Erysimum asperum var. pumilum S. Watson Erysimum bakeri Rydberg Erysimum capitatum var. amoenum (Greene) R. J. Davis Erysimum capitatum var. argillosum (Greene) R. J. Davis Erysimum capitatum var. nivale (Greene) N. H. Holmgren Erysimum cockerellianum Erysimum desertorum Erysimum nivale Erysimum oblanceolatum Erysimum radicatum
Treatment appears in FNA Volume 7. Treatment on page 538. Mentioned on page 537.

Proximal leaves with mostly 2- or 3-rayed trichomes adaxially. Flowers: petals usually yellow, rarely lavender or purplish. Fruits usually 4-angled, rarely latiseptate. Seeds 1.5–2(–2.4) × 0.7–1.2 mm; not winged. 2n = 36.


Phenology: Flowering Apr–Sep.
Habitat: Meadows, dry slopes, hillsides
Elevation: 1000-3800 m

Distribution

V7 851-distribution-map.gif

Yukon, Alaska, Ariz., Calif., Colo., Idaho, Mont., Nev., N.Mex., Tex., Utah, Wyo., Mexico (Chihuahua, Michoacán, Sonora, Zacatecas).

Discussion

Plants of var. purshii were placed by G. B. Rossbach (1958) in three species (Erysimum angustatum, E. argillosum, E. desertorum) and by R. C. Rollins (1993) in two species (E. angustatum, E. capitatum). The considerable overlap in morphology and the frequent hybridization between vars. capitatum and purshii in areas where their geographical ranges meet argue against such delimitation. Forms with linear leaves to 3 mm wide, which are restricted to eastern Alaska and western Yukon, were recognized by Rossbach and Rollins as E. angustatum, but these hardly differ from typical var. purshii in all other characters.

Selected References

None.

Lower Taxa

None.
Ihsan A. Al-Shehbaz +
(Durand) Rollins +
Erysimum asperum var. purshii +
Yukon +, Alaska +, Ariz. +, Calif. +, Colo. +, Idaho +, Mont. +, Nev. +, N.Mex. +, Tex. +, Utah +, Wyo. +, Mexico (Chihuahua +, Michoacán +, Sonora +  and Zacatecas). +
1000-3800 m +
Meadows, dry slopes, hillsides +
Flowering Apr–Sep. +
Cruciferae Continental N. Amer., +
Cheiranthus alpestris +, Cheiranthus argillosus +, Cheiranthus aridus +, Cheiranthus asperrimus +, Cheiranthus bakeri +, Cheiranthus nivalis +, Cheiranthus nivalis var. amoenus +, Cheiranthus oblanceolatus +, Cheiranthus radicatus +, Cheirinia amoena +, Cheirinia argillosa +, Cheirinia arida +, Cheirinia asperrima +, Cheirinia bakeri +, Cheirinia brachycarpa +, Cheirinia cockerelliana +, Cheirinia desertorum +, Cheirinia nivalis +, Cheirinia nivalis var. radicata +, Cheirinia oblanceolata +, Cheirinia radicata +, Erysimum amoenum +, Erysimum angustatum +, Erysimum argillosum +, Erysimum aridum +, Erysimum asperrimum +, Erysimum asperum var. amoenum +, Erysimum asperum var. angustatum +, Erysimum asperum var. pumilum +, Erysimum bakeri +, Erysimum capitatum var. amoenum +, Erysimum capitatum var. argillosum +, Erysimum capitatum var. nivale +, Erysimum cockerellianum +, Erysimum desertorum +, Erysimum nivale +, Erysimum oblanceolatum +  and Erysimum radicatum +
Erysimum capitatum var. purshii +
Erysimum capitatum +
variety +