Descurainia kenheilii
Author: Al-Shehbaz


Heil's tansy mustard


Brassicaceae (Mustard Family)

Close up of Descurainia kenheilii: not available

Taxonomic Comments

A new species described in 2007 (Al-Shehbaz 2007).

Ranks and Status

Global rank: G1
State rank: S1
Federal protection status: None
State protection status: None

[+] Description and Phenology

Descurainia kenheilii by Ihsan Al-Shehbaz
Click image to enlarge.

General description: Diminutive, short-lived perennial with yellowish flowers. Plants are 0.1-0.15 dm tall, erect, simple or rarely few branched above. Basal and lowermost cauline leaves are pinnate, and oblanceolate in outline. Racemes are not elongated in fruit; fruiting pedicels are erect to ascending. Plants are sparsely pubescent throughout with dendritic trichomes (Al-Shehbaz 2007).

Look Alikes: From D. torulosa, D. kenheilii is easily distinguished by having glabrous (vs. sparsely pubescent) fruit valves and styles, prominently veined (vs. veinless) septa, 4-8 (vs. 10-18) seeds and ovules per fruit, uniseriate (vs. biseriate) seeds, straight (vs. curved outward) and non-appressed (vs. basally appressed) fruits 1.0-1.3 (vs. 0.6-0.8) mm wide, and not elongated (vs. considerably elongated) fruiting racemes (Al-Shehbaz 2007).

Phenology: The one known specimen of this species was collected with flowers and fruit on September 13, 1997 (Colorado Natural Heritage Program 2012).

[+] Habitat

Habitat of Descurainia kenheilii by Peggy Lyon
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The one known location was found in alpine tundra on thin soil and talus slopes, on an andesite porphyry and rhyolite tuff substrate (Al-Shehbaz 2007).

Elevation Range: 12,208 - 12,953 feet (3,721 - 3,948 meters)

[+] Distribution

Distribution of Descurainia kenheilii in Colorado
Click image to enlarge.

Colorado endemic: Yes
Global range: Endemic to Colorado, San Juan County.

[+] Threats and Management Issues

No site-specific threats known. Alipine species may be particularly vulnerable to climate change.

[+] References

    • Ackerfield, J. 2012. The Flora of Colorado. Colorado State University Herbarium. 433 pp.
    • Al-Shehbaz, I.A. 2007. Descurainia kenheilii (Brassicaceae), A new species from the San Juan Mountains, Colorado. Harvard Papers in Botany, 12(2): 395-396.
    • Colorado Natural Heritage Program. 2005. The Second Annual Colorado Rare Plant Symposium: G1 Plants of Colorado. Symposium Minutes. Available on-line http://www.cnhp.colostate.edu/teams/botany.asp#symposia.
    • Colorado Natural Heritage Program. 2010. The Seventh Annual Colorado Rare Plant Symposium: G1 Plants of Colorado. Symposium Minutes. Available on-line http://www.cnhp.colostate.edu/teams/botany.asp#symposia.
    • Colorado Natural Heritage Program. 2012. Biodiversity Tracking and Conservation System. Colorado State University, Fort Collins, CO.
    • Flora of North America Editorial Committee, ed. (FNA). 1993+. Flora of North America North of Mexico. Oxford Univ. Press, New York, Oxford.
    • Heil, K.D., S.L. O'Kane Jr., L.M. Reeves, and A. Clifford, 2013. Flora of the Four Corners Region, Vascular Plants of the San Juan River Drainage; Arizona, Colorado, New Mexico, and Utah. Missouri Botanical Garden Press, St. Louis, Missouri. 1098 pp.
    • Lavender, A.E., M.M. Fink, S.E. Linn, D.M. Theobald. 2011. Colorado Ownership, Management, and Protection v9 Database. Colorado Natural Heritage Program and Geospatial Centroid, Colorado State University, Fort Collins, CO. (30 September).
    • Neely, B., S. Panjabi, E. Lane, P. Lewis, C. Dawson, A. Kratz, B. Kurzel, T. Hogan, J. Handwerk, S. Krishnan, J. Neale, and N. Ripley. 2009. Colorado Rare Plant Conservation Strategy, Developed by the Colorado Rare Plant conservation Initiative. The Nature Conservancy, Boulder, Colorado, 117 pp.
    • Weber, W. A. and R. C. Wittmann. 2012. Colorado Flora, Western Slope, A Field Guide to the Vascular Plants, Fourth Edition. Boulder, Colorado. 532 pp.

Last Updated

2012-11-05