Mentzelia decapetala |
Mentzelia lagarosa |
|
---|---|---|
10-petal western star, evening starflower, gumbo-lily, tenpetal blazingstar |
slender-lobed blazingstar |
|
Habit | Plants biennial or perennial, bushlike, perennials with ground-level caudices. | Plants biennial, candelabra-form. |
Stems | solitary, erect, straight; branches distal or along entire stem, proximal or distal longest, antrorse, straight to upcurved; hairy. |
solitary, erect, straight; branches distal, distal longest, antrorse, straight; hairy. |
Leaves | blade 72–295 × 14–45 mm, widest intersinus distance 10.1–23.3 mm; proximal oblanceolate or elliptic, margins serrate to pinnate, teeth or lobes 16–26, slightly antrorse, 1–16.5 mm; distal elliptic to lanceolate, base clasping or not, margins serrate to pinnate, teeth or lobes 9–20, slightly antrorse, 5.3–13.7 mm; surfaces with needlelike trichomes. |
blade 11.3–103 × 4.8–20.1 mm, widest intersinus distance 1.2–5.7 mm; proximal oblanceolate to elliptic, margins pinnate to pinnatisect, lobes 8–20, slightly antrorse or perpendicular to leaf axis, 1.4–8.2 mm; distal elliptic to lanceolate, base not clasping, margins pinnatisect, lobes 6–16, slightly antrorse or perpendicular to leaf axis, 1.6–7.5 mm; abaxial surface with simple grappling-hook, complex grappling-hook, and occasionally needlelike trichomes, adaxial surface with simple grappling-hook and needlelike trichomes. |
Bracts | margins pinnate. |
margins usually entire, sometimes toothed or pinnate. |
Flowers | petals white, 47–75 × 13–22.7 mm, apex acute to attenuate, glabrous abaxially; stamens white to yellow, 5 outermost petaloid, filaments spatulate, strongly clawed, 48–75 × 12–23 mm, without anthers, second whorl with anthers; anthers straight after dehiscence, epidermis smooth; styles 36–53 mm. |
petals golden yellow, 8.3–13 × 2.2–5.4 mm, apex acute or rounded, glabrous abaxially; stamens golden yellow, 5 outermost petaloid, filaments narrowly spatulate, slightly clawed, 6.5–10.7 × 1.7–4.3 mm, without anthers, second whorl with anthers; anthers straight after dehiscence, epidermis smooth; styles 6.1–10.2 mm. |
Capsules | cylindric, 30–43 × 12–17 mm, base tapering, not longitudinally ridged. |
cylindric, 12.1–21.2 × 4.9–7.6 mm, base tapering or rounded, not longitudinally ridged. |
Seeds | 2.3–4 mm; coat anticlinal cell walls straight, papillae 4–10 per cell. |
coat anticlinal cell walls wavy, papillae 29–31 per cell. |
2n | = 22. |
= 22. |
Mentzelia decapetala |
Mentzelia lagarosa |
|
Phenology | Flowering Jun–Aug(–Oct). | Flowering Jun–Aug(–Oct). |
Habitat | Rock outcrops, slopes, dry short-grass prairies, riverbanks, roadsides, loam, limestone, sandy, silty, clayey, and gravelly soils. | Sparsely vegetated hills, slopes, knolls, white ash and limestone soils. |
Elevation | 300–2400 m. (1000–7900 ft.) | 1500–2500 m. (4900–8200 ft.) |
Distribution |
CO; IA; IL; KS; MN; MT; NE; NM; OK; SD; TX; UT; WY; AB; MB; SK
|
CO; NV; UT |
Discussion | Mentzelia decapetala is introduced in Grundy County, Illinois. It appears to be native throughout the rest of its distribution. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Mentzelia lagarosa is allopatric with two of the three species most similar to it, namely M. holmgreniorum and M. filifolia, and nearly allopatric with the third, M. laciniata. Where the ranges of M. lagarosa and M. laciniata overlap in western Colorado, they can be distinguished by petal length [8.3–13 mm in M. lagarosa versus 14–23.8(–26) mm in M. laciniata], outermost stamen length (6.5–10.7 mm in M. lagarosa versus 12–20 mm in M. laciniata), and number of seed coat cell papillae (29–31 per cell in M. lagarosa versus 5–14 per cell in M. laciniata); in addition, M. lagarosa bears both simple grappling-hook and needlelike trichomes on its adaxial leaf blade surfaces, whereas leaf blades of M. laciniata bear only needlelike trichomes adaxially. In the Intermountain Flora, N. H. Holmgren et al. (2005) treated M. lagarosa as a synonym of M. multiflora, but J. J. Schenk and L. Hufford (2011) showed not only that M. lagarosa is distinct from M. multiflora, but also that the latter does not occur in the intermountain region. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 504. | FNA vol. 12, p. 516. |
Parent taxa | Loasaceae > Mentzelia > sect. Bartonia | Loasaceae > Mentzelia > sect. Bartonia |
Sibling taxa | ||
Synonyms | Bartonia decapetala | M. pumila var. lagarosa |
Name authority | (Pursh) Urban: Ber. Deutsch. Bot. Ges. 10: 263. (1892) | (K. H. Thorne) J. J. Schenk & L. Hufford: Madroño 57: 247. (2010) |
Web links |