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

10-petal western star, evening starflower, gumbo-lily, tenpetal blazingstar

grass blazingstar, Raven's blazingstar

Habit Plants biennial or perennial, bushlike, perennials with ground-level caudices. Plants candelabra-form, (5–)20–45 cm.
Stems

solitary, erect, straight;

branches distal or along entire stem, proximal or distal longest, antrorse, straight to upcurved; 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.

Basal leaves

persisting;

petiole present or absent;

blade linear-lanceolate, margins deeply to shallowly lobed.

Cauline leaves

petiole absent;

blade ovate-lanceolate to lanceolate, to 18 cm, margins deeply lobed to dentate.

Bracts

margins pinnate.

green with prominent white base usually conspicuously extending outwards from midvein, ovate, 5.6–8.4 × 1.8–3.9 mm, width 1/5–2/3 length, not concealing capsule, margins 3–5-lobed.

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.

sepals 2–6 mm;

petals orange proximally, yellow distally, 5–11(–13) mm, apex retuse;

stamens 20+, 3–7 mm, filaments monomorphic, filiform, unlobed;

styles 3.5–8 mm.

Capsules

cylindric, 30–43 × 12–17 mm, base tapering, not longitudinally ridged.

clavate, 8–23 × 2–3 mm, axillary curved to 45° at maturity, usually inconspicuously longitudinally ribbed.

Seeds

2.3–4 mm;

coat anticlinal cell walls straight, papillae 4–10 per cell.

15–30, in 2+ rows distal to mid fruit, tan, dark-mottled, usually irregularly polygonal, occasionally triangular prisms proximal to mid fruit, surface tuberculate under 10x magnification; recurved flap over hilum absent;

seed coat cell outer periclinal wall domed, domes on seed edges more than or equal to 1/2 as tall as wide at maturity.

2n

= 22.

= 36.

Mentzelia decapetala

Mentzelia ravenii

Phenology Flowering Jun–Aug(–Oct). Flowering Mar–May.
Habitat Rock outcrops, slopes, dry short-grass prairies, riverbanks, roadsides, loam, limestone, sandy, silty, clayey, and gravelly soils. Sandy desert foothills, roadsides, desert scrub, Joshua-tree woodlands.
Elevation 300–2400 m. (1000–7900 ft.) 300–1200 m. (1000–3900 ft.)
Distribution
from FNA
CO; IA; IL; KS; MN; MT; NE; NM; OK; SD; TX; UT; WY; AB; MB; SK
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
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 ravenii is narrowly distributed, with most populations limited to desert foothills on the northern edge of the San Gabriel Mountains in northeastern Los Angeles County. Populations of M. ravenii with relatively large flowers with yellow petals are often found growing under desert shrubs in mixed populations with M. veatchiana, which has relatively small flowers with orange petals in this area. A few tetraploid populations from western Riverside County have also been called M. ravenii (J. E. Zavortink 1966); further work is needed to confirm that these represent the same species. See 72. M. gracilenta for discussion of similarities it shares with M. ravenii.

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

Source FNA vol. 12, p. 504. FNA vol. 12, p. 541.
Parent taxa Loasaceae > Mentzelia > sect. Bartonia Loasaceae > Mentzelia > sect. Trachyphytum
Sibling taxa
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. 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. 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
Synonyms Bartonia decapetala
Name authority (Pursh) Urban: Ber. Deutsch. Bot. Ges. 10: 263. (1892) H. J. Thompson & J. E. Roberts: Phytologia 21: 285. (1971)
Web links