Flora of North America species comparison

The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Descurainia longepedicellata

Descurainia brevisiliqua

mountain tansymustard, narrow tansymustard, sticky tansymustard, western tansy-mustard
Habit Annuals; usually eglandular, rarely glandular; moderately to sparsely pubescent, often glabrous distally, not canescent, trichomes dendritic. Biennials; eglandular; finely pubescent, often canescent, trichomes dendritic, rarely also mixed with simple ones.
Stems

erect, unbranched or branched proximally, often branched distally, (1.5–)3–6.2(–8.5) dm.

erect, unbranched basally, branched distally, 6–11 dm.
Basal leaves

petiole 0.4–3.5 cm;

blade pinnate, ovate to oblanceolate in outline, 1.5–7 cm, lateral lobes linear or oblong, margins entire or dentate to incised.

petiole 0.5–1.5 cm;

blade pinnate, oblanceolate to obovate or ovate in outline, 1–5 cm, lateral lobes (2–5 pairs), linear, margins entire or serrate to incised (apex obtuse).
Cauline leaves

sessile or shortly petiolate;

blade smaller distally, lobes linear to filiform, margins entire, surfaces usually glabrous, rarely pubescent.

sessile or shortly petiolate;

blade smaller distally, distal lobes often narrower, surfaces densely pubescent.
Racemes

considerably elongated in fruit.

(paniculate, often with short branches), considerably elongated in fruit.
Flowers

sepals ascending, yellow, oblong, 1.5–2 mm, glabrous;

petals narrowly oblanceolate, 1.7–2.6 cm × 0.5–1 mm;

median filaments 1.5–2 mm;

anthers 0.3–0.4 mm.

sepals spreading, yellowish, oblong, 1.4–2 mm, pubescent, (trichomes dendritic, sometimes mixed with simple ones);

petals oblanceolate, 0.7–1 × 0.1–0.2 mm;

median filaments 1.5–2 mm;

anthers 0.2–0.3 mm.
Fruiting pedicels

horizontal to divaricate, straight, (8–)10–15(–20) mm.

divaricate-ascending, straight, 4–7(–11) mm.
Fruits

erect, linear, not torulose, (9–)12–17 × 0.8–1.1 mm, (straight or slightly curved inward);

valves each with obscure midvein;

septum not veined;

ovules 18–32 per ovary;

style 0.1–0.2 mm, glabrous.

divaricate to erect, linear to oblong, not torulose, 3–8(–10) × 1–1.2 mm;

valves each with distinct midvein;

septum not veined;

ovules 10–28 per ovary;

style obsolete to 0.1 mm, glabrous.
Seeds

uniseriate, reddish brown, oblong, 1–1.3 × 0.6–0.7 mm.

biseriate, light brown, ellipsoid, 0.5–0.7 × 0.3–0.4 mm.
2n

= 14.

= 42.

Descurainia longepedicellata

Descurainia brevisiliqua
Phenology Flowering Apr–Jul. Flowering (late Jun-)Jul–Aug(-early Oct).
Habitat Sandy plains and banks, dry washes, open hillsides, sagebrush and juniper or pine communities, grasslands Pine and juniper communities, rocky washes, roadsides, grasslands, gravelly mesa
Elevation 200-2100 m (700-6900 ft) 1900-2500 m (6200-8200 ft)
Distribution
from FNA
AZ; CO; ID; MT; NV; OR; UT; WA; WY; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; NM; TX
[BONAP county map]
Discussion

L. E. Detling (1939) treated Descurainia longepedicellata as subsp. filipes of D. pinnata, whereas R. C. Rollins (1993) and N. H. Holmgren (2005b) treated it as a subspecies and variety, respectively, of D. incisa. Molecular data, both nuclear and plastidic (B. E. Goodson 2007), place the three taxa in different, well-supported clades.

R. C. Rollins (1993) and N. H. Holmgren (2005b) reported 2n = 28 and 42 for Descurainia longepedicellata (as D. pinnata var. filipes), but these counts are not vouchered. Rollins indicated that the taxon range extends into California and New Mexico; we have not seen material from those states.

Descurainia longepedicellata resembles D. incisa subsp. paysonii in having long fruiting pedicels and linear leaf lobes with entire margins. The latter is easily distinguished by being canescent (versus not canescent) and having fruits strongly curved inward (versus straight). Because the two taxa are not closely related (B. E. Goodson 2007), the similarities in fruiting pedicels and distalmost leaf segments represent convergence.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

R. C. Rollins (1993) reduced Descurainia brevisiliqua to synonymy of the diploid D. obtusa. This hexaploid species differs from the latter in having biseriate (versus uniseriate) seeds and glabrous (versus densely to moderately pubescent) fruits. Molecular data (B. E. Goodson 2007) show that it is consistently separate from, and unrelated to, D. obtusa, instead being affiliated with D. incana and D. incisa. Descurainia brevisiliqua differs from the latter two species by having biseriate (versus uniseriate) seeds and oblong, non-torulose fruits that, unlike those of D. incana, are not appressed to rachises. Although the fruits of D. brevisiliqua resemble those of some D. pinnata subspecies, it can be readily distinguished from the latter by its tall, strict growth habit with numerous short branches in the distal part of the plant, more linear leaf segments, stems that are usually purple, and late–summer flowering period.

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Source FNA vol. 7, p. 524. FNA vol. 7, p. 521.
Parent taxa Brassicaceae > tribe Descurainieae > Descurainia Brassicaceae > tribe Descurainieae > Descurainia
Sibling taxa
D. adenophora, D. brevisiliqua, D. californica, D. incana, D. incisa, D. kenheilii, D. nelsonii, D. obtusa, D. paradisa, D. pinnata, D. sophia, D. sophioides, D. torulosa
D. adenophora, D. californica, D. incana, D. incisa, D. kenheilii, D. longepedicellata, D. nelsonii, D. obtusa, D. paradisa, D. pinnata, D. sophia, D. sophioides, D. torulosa
Synonyms Sisymbrium longepedicellatum, D. brachycarpa var. eglandulosa, D. incisa subsp. filipes, D. incisa var. filipes, D. longepedicellata var. glandulosa, D. pinnata subsp. filipes, D. pinnata var. filipes, D. rydbergii var. eglandulosa, Hesperis longepedicellata, Sisymbrium brachycarpum var. filipes, Sisymbrium incisum var. filipes, Sisymbrium incisum var. xerophilum, Sisymbrium longepedicellatum var. glandulosum, Sophia filipes, Sophia glandifera, Sophia gracilis, Sophia longepedicellata D. obtusa subsp. brevisiliqua
Name authority (E. Fournier) O. E. Schulz: in H. G. A. Engler, Pflanzenr. 86[IV,105]: 324. (1924) (Detling) Al-Shehbaz & Goodson: Harvard Pap. Bot. 12: 421. (2007)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Fabaceae, Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America, OregonFlora, UW Burke Herbarium

The species comparison tool is brought to you by:
Northwest Wildflowers