Smelowskia

Plants cespitose, caudex well-developed, thick, often-branched, covered with persistent petiolar remains; not scapose; usually pubescent. Stems erect to decumbent, unbranched or branched distally, densely pubescent. Leaves basal and cauline; petiolate or sessile; basal rosulate, petiolate, blade margins usually 1- or 2-pinnatisect, rarely entire. Racemes (corymbose, several-flowered), often considerably elongated in fruit. Fruiting pedicels ascending, spreading, suberect, or divaricate [recurved], slender. Flowers: sepals (sometimes persistent), oblong [ovate]; petals spatulate to obovate or suborbicular, (longer than sepals), claw differentiated from blade, (apex rounded); stamens slightly tetradynamous; filaments often dilated basally; anthers ovate or oblong, (apex obtuse); nectar glands usually confluent, subtending bases of stamens, median glands present or not. Fruits siliques or silicles, usually sessile, rarely shortly stipitate, linear, oblong, obovoid, ellipsoid, spatulate, oblanceolate, suboblong, or pyriform [fusiform, ovoid, suborbicular], smooth, 4-angled, angustiseptate, terete, or subterete [latiseptate]; valves each with prominent or obscure midvein, usually glabrous; replum rounded; septum complete or perforated; ovules 4–18 per ovary; stigma capitate. Seeds plump, not winged, usually oblong, rarely oblong-lanceolate; seed coat (minutely reticulate), not mucilaginous when wetted; cotyledons incumbent or accumbent.

Distribution

North America, e, c Asia.

Discussion

Species 25 (7 in the flora).

Selected References

Al-Shehbaz, I. A. and S. I. Warwick. 2006. A synopsis of Smelowskia (Brassicaceae). Harvard Pap. Bot. 11: 91–99.

Drury, W. H. Jr. and R. C. Rollins. 1952. The North American representatives of Smelowskia (Cruciferae). Rhodora 54: 85–119.

Velichkin, E. M. 1979. Smelowskia C. A. Mey. (Cruciferae). Critical review and relation to close genera. Bot. Zhurn. (Moscow & Leningrad) 64: 153–171.

Warwick, S. I. et al. 2004b. Phylogeny of Smelowskia and related genera (Brassicaceae) based on nuclear ITS DNA and chloroplast trnL intron DNA sequences. Ann. Missouri Bot. Gard. 91: 99–123.

Lower Taxa

Smelowskia americana, Smelowskia borealis, Smelowskia johnsonii, Smelowskia media, Smelowskia ovalis, Smelowskia porsildii, Smelowskia pyriformis

Key

1	Basal leaves: blade margins entire, apically 3 or 5-toothed or -lobed, or palmately lobed	> 2
1	Basal leaves: blade margins 1- or 2-pinnatisect or pinnatifid	> 4
2	Basal leaves: blade margins deeply palmately (3 or) 5 (or 7)-lobed; fruiting pedicels secund; sepals usually persistent; fruits angustiseptate, (8-)12-28 × 4-8 mm; ovules 10-18 per ovary.	Smelowskia borealis
2	Basal leaves: blade margins entire or apically 3 or 5-toothed or -lobed; fruiting pedicels not secund; sepals caducous; fruits subterete or slightly 4-angled, 5-10 × 1.5-3 mm; ovules 4-8 per ovary	> 3
3	Basal leaf blade surfaces densely silvery villous, trichomes mostly simple, 1-1.8 mm; petals lavender to purplish; fruiting pedicels 11-27 mm; fruit valves each with obscure midvein; ovules 4 per ovary; seeds 2.2-2.7 mm.	Smelowskia johnsonii
3	Basal leaf blade surfaces densely grayish tomentose, trichomes mostly dendritic with fewer simple ones, to 1 mm; petals white or creamy white; fruiting pedicels 4-12 mm; fruit valves each with prominent midvein; ovules 4-8 per ovary; seeds 1.5-2 mm.	Smelowskia porsildii
4	Sepals persistent; fruits 2-6 mm, bases obtuse, valves each with obscure midvein.	Smelowskia ovalis
4	Sepals caducous; fruits 5-13 mm, bases cuneate, valves each with prominent midvein	> 5
5	Fruits pyriform, subterete, apices rounded; ovules 4 per ovary; seeds 2.5-3.2 × 1-1.5 mm.	Smelowskia pyriformis
5	Fruits fusiform, ellipsoid, oblong, or linear, 4-angled, apices cuneate; ovules 8-12 (-14) per ovary; seeds 1.1-2.2 × 0.6-1.1 mm	> 6
6	Fruiting pedicels suberect to ascending, subappressed to rachises, forming less than 40˚ angle; seeds 1.1-1.9 × 0.6-0.9 mm; Alberta, British Columbia, Mountain and Pacific states.	Smelowskia americana
6	Fruiting pedicels usually spreading to divaricate, rarely divaricate-ascending, not appressed to rachises, often forming greater than 40˚ angle; seeds 1.7-2.2 × 0.9-1.1 mm; Alaska, Northwest Territories, Yukon.	Smelowskia media