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

dal-pega, rough stickleaf, tropical blazingstar, tropical stickleaf

Torrey's blazing star

Habit Plants annual, without caudices or tubers. Plants with ground-level or subterranean caudices.
Stems

erect to decumbent, to 30 cm.

5–25 cm.

Leaves

petiole 10–65 mm;

blade hastate to ovate, usually basally lobed, sometimes unlobed, to 18 × 10 cm, base cuneate to truncate, margins serrate to crenate, apex acute.

petiole absent;

blade ovate or obovate, to 45 × 35 mm, intersinus distance 2–4 mm.

Pedicels

(fruiting) 1–3 × 2 mm (often appearing absent because thick and continuous with capsule).

0(–1.5) mm.

Flowers

petals orange or yellow, 5–15 × 3–7 mm, apex cuspidate, hairy abaxially at apex;

stamens 20–30, 5 mm, filaments heteromorphic, 5 outermost narrowly spatulate, inner filiform;

style 5 mm.

petals yellow to orange, narrowly spatulate to obovate, 4.5–17 × 1.2–5 mm, apex rounded;

stamens 25–45, 7–21 mm;

styles 7–18 mm.

Capsules

subcylindric to clavate, 9–30 × 3–3.5 mm, base tapering gradually, capsule and pedicel not well-differentiated.

3–7 × 3–4.5 mm.

Seeds

5–9 per capsule, pyriform to oblong, without transverse folds.

3–9 per capsule, edges prominently to inconspicuously ridged.

2n

= 20.

= 28.

Mentzelia aspera

Mentzelia torreyi

Phenology Flowering Aug–Oct.
Habitat Arroyo and canyon bottoms, grasslands, desert scrub, riparian cottonwood and willow vegetation.
Elevation 100–2000 m. (300–6600 ft.)
Distribution
from FNA
AZ; Mexico; Central America; South America; West Indies [Introduced in Atlantic Islands (Cape Verde Islands)]
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; ID; NV
[WildflowerSearch map]
[BONAP county map]
Discussion

Mentzelia aspera is uncommon in southern Arizona. It is the most widespread species of the genus and is regarded as weedy by some authors (H. J. Thompson and A. M. Powell 1981).

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

Varieties 2 (2 in flora).

In the phylogenetic study by L. Hufford et al. (2003), Mentzelia torreyi was recovered as the sister to the rest of the genus.

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

Key
1. Petals 8–17 mm, yellow; longest stamens to 1 mm longer than petals.
var. torreyi
1. Petals 4.5–8 mm, orangish yellow, orange, or burnt orange; longest stamens usually much more than 1 mm longer than petals.
var. acerosa
Source FNA vol. 12, p. 528. FNA vol. 12, p. 530.
Parent taxa Loasaceae > Mentzelia > sect. Mentzelia Loasaceae > Mentzelia > sect. Micromentzelia
Sibling taxa
M. affinis, M. albescens, M. albicaulis, M. argillicola, M. argillosa, 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. 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. tricuspis, M. tridentata, M. uintahensis, M. veatchiana
Subordinate taxa
M. torreyi var. acerosa, M. torreyi var. torreyi
Name authority Linnaeus: Sp. Pl. 1: 516. (1753) A. Gray: Proc. Amer. Acad. Arts 10: 72. (1874)
Web links