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

wavy-leaf blazingstar

blazing-star mentzelia, common blazing-star, giant blazing-star, smooth-stem blazingstar

Habit Plants biennial, candelabra-form. Plants biennial or perennial (in rosette stage), bushlike.
Stems

solitary, erect, straight;

branches distal, distal longest, antrorse, straight; hairy.

solitary, erect, straight;

branches distal or along entire stem, proximal or distal longest, antrorse, upcurved; hairy or glabrescent.

Leaves

blade 31–92(–157) × 10.5–27.6(–41) mm, widest intersinus distance 5.2–23.3(–29) mm;

proximal lanceolate or elliptic, margins serrate to pinnate, teeth or lobes 8–22, slightly antrorse, 1.8–6 mm;

distal lanceolate, base clasping, margins usually serrate to pinnate, occasionally entire, teeth or lobes (0–)10–20, slightly antrorse, 1.4–7.6 mm;

abaxial surface with simple grappling-hook, complex grappling-hook, and needlelike trichomes, adaxial surface with simple grappling-hook and needlelike trichomes.

blade 17.4–196 × 6.7–40.4 mm, widest intersinus distance 2.4–24.6 mm;

proximal oblanceolate, lanceolate, or elliptic, margins pinnate, lobes 14–44, slightly antrorse, 2.5–8.9 mm;

distal lanceolate, base clasping or not, margins pinnate, lobes 6–42, slightly antrorse, 2.1–13.8 mm;

abaxial surface with simple grappling-hook, complex grappling-hook, and needlelike trichomes, adaxial surface with needlelike trichomes.

Bracts

margins entire.

margins entire or pinnate.

Flowers

petals golden yellow, 5.7–9.2 × 1.3–3 mm, apex usually acute, occasionally rounded, glabrous abaxially;

stamens golden yellow, 5 outermost petaloid, filaments narrowly spatulate, slightly clawed, 4.7–8.4 × 1–2.4 mm, without anthers, second whorl with anthers;

anthers straight after dehiscence, epidermis smooth;

styles 3.5–5.4 mm.

petals golden yellow, 23.5–70 × 3–17.3 mm, apex acute, glabrous abaxially;

stamens golden yellow, 5 outermost not petaloid, filaments linear to narrowly elliptic, not clawed, 17.7–55 × 0.5–2(–2.5) mm, with anthers, second whorl with anthers;

anthers straight after dehiscence, epidermis smooth;

styles 20.4–57 mm.

Capsules

cylindric, 13.6–23.5 × 5.1–7.8 mm, base tapering, not or slightly longitudinally ridged.

cup-shaped to cylindric, 10.6–43 × 6.3–11.1 mm, base tapering or rounded, not longitudinally ridged.

Seeds

coat anticlinal cell walls straight, papillae 4–17 per cell.

coat anticlinal cell walls straight, papillae 4–11 per cell.

2n

= 22.

= 22.

Mentzelia albescens

Mentzelia laevicaulis

Phenology Flowering May–Nov.
Habitat Dry grasslands, xeric habitats of arroyos, roadsides, roadcuts, washes, chat piles, slopes.
Elevation 200–1600 m. (700–5200 ft.)
Distribution
from FNA
KS; MO; OK; TX; South America (Argentina, Chile)
[BONAP county map]
from FNA
AZ; CA; ID; MT; NV; OR; UT; WA; WY; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

Phylogenetic analyses (J. J. Schenk and L. Hufford 2011) recovered representative populations of Mentzelia albescens from Texas and South America in a monophyletic group. Phylogenetic placement of these populations among lineages in sect. Bartonia, as well as a lack of morphological differentiation among North American and South American populations, suggests a recent dispersal to South America. In the flora area, this species is native to central and western Texas, and introduced in Kansas, Missouri, and Oklahoma.

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

Varieties 2 (2 in the flora).

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

Key
1. Petals 43–70 mm; 5 outermost stamens 39–55 mm.
var. laevicaulis
1. Petals 23.5–40 mm; 5 outermost stamens 17.7–29 mm.
var. parviflora
Source FNA vol. 12, p. 518. FNA vol. 12, p. 514.
Parent taxa Loasaceae > Mentzelia > sect. Bartonia Loasaceae > Mentzelia > sect. Bartonia
Sibling taxa
M. affinis, M. albicaulis, M. argillicola, M. argillosa, M. aspera, M. asperula, M. candelariae, M. canyonensis, M. chrysantha, M. collomiae, M. congesta, M. conspicua, M. crocea, M. cronquistii, M. decapetala, M. densa, M. desertorum, M. dispersa, M. eremophila, M. filifolia, M. floridana, M. flumensevera, M. goodrichii, M. gracilenta, M. hirsutissima, M. holmgreniorum, M. hualapaiensis, M. humilis, M. integra, M. involucrata, M. inyoensis, M. isolata, M. jonesii, M. laciniata, M. laevicaulis, M. lagarosa, M. leucophylla, M. librina, M. lindheimeri, M. lindleyi, M. longiloba, M. marginata, M. memorabilis, M. mexicana, M. micrantha, M. mollis, M. monoensis, M. montana, M. multicaulis, M. multiflora, M. nitens, M. nuda, M. obscura, M. oligosperma, M. oreophila, M. pachyrhiza, M. packardiae, M. paradoxensis, M. pectinata, M. perennis, M. polita, M. procera, M. pterosperma, M. puberula, M. pumila, M. ravenii, M. reflexa, M. reverchonii, M. rhizomata, M. rusbyi, M. saxicola, M. shultziorum, M. sivinskii, M. speciosa, M. springeri, M. strictissima, M. thompsonii, M. tiehmii, M. todiltoensis, M. torreyi, M. tricuspis, M. tridentata, M. uintahensis, M. veatchiana
M. affinis, M. albescens, M. albicaulis, M. argillicola, M. argillosa, M. aspera, M. asperula, M. candelariae, M. canyonensis, M. chrysantha, M. collomiae, M. congesta, M. conspicua, M. crocea, M. cronquistii, M. decapetala, M. densa, M. desertorum, M. dispersa, M. eremophila, M. filifolia, M. floridana, M. flumensevera, M. goodrichii, M. gracilenta, M. hirsutissima, M. holmgreniorum, M. hualapaiensis, M. humilis, M. integra, M. involucrata, M. inyoensis, M. isolata, M. jonesii, M. laciniata, M. lagarosa, M. leucophylla, M. librina, M. lindheimeri, M. lindleyi, M. longiloba, M. marginata, M. memorabilis, M. mexicana, M. micrantha, M. mollis, M. monoensis, M. montana, M. multicaulis, M. multiflora, M. nitens, M. nuda, M. obscura, M. oligosperma, M. oreophila, M. pachyrhiza, M. packardiae, M. paradoxensis, M. pectinata, M. perennis, M. polita, M. procera, M. pterosperma, M. puberula, M. pumila, M. ravenii, M. reflexa, M. reverchonii, M. rhizomata, M. rusbyi, M. saxicola, M. shultziorum, M. sivinskii, M. speciosa, M. springeri, M. strictissima, M. thompsonii, M. tiehmii, M. todiltoensis, M. torreyi, M. tricuspis, M. tridentata, M. uintahensis, M. veatchiana
Subordinate taxa
M. laevicaulis var. laevicaulis, M. laevicaulis var. parviflora
Synonyms Bartonia albescens, B. wrightii Bartonia laevicaulis
Name authority (Gillies ex Arnott) Bentham & Hooker f. ex Grisebach: Abh. Königl. Ges. Wiss. Göttingen 19: 150. (1874) (Douglas) Torrey & A. Gray: Fl. N. Amer. 1: 535. (1840)
Web links