Mentzelia albescens
Mentzelia speciosa
wavy-leaf blazingstar
jeweled blazingstar, showy western star
solitary, erect, straight;
branches distal, distal longest, antrorse, straight; hairy.
solitary, erect, straight;
branches distal or along entire stem, distal or proximal longest, antrorse, upcurved; hairy.
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 43.6–233 × 9.2–34.7 mm, always some longer than 146 mm, widest intersinus distance 5.2–17 mm;
proximal oblanceolate to elliptic, margins serrate to pinnate, teeth or lobes 10–38, slightly antrorse, 1.5–9.4 mm;
distal lanceolate, base not clasping, margins serrate to pinnate, teeth or lobes 8–24, slightly antrorse, 2.9–10.3 mm;
abaxial surface with simple grappling-hook, complex grappling-hook, and needlelike trichomes, adaxial surface with simple grappling-hook and needlelike trichomes.
margins entire.
margins entire.
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, 14.4–28.6 × 3.8–8 mm, apex acute to rounded, glabrous abaxially;
stamens golden yellow, 5 outermost petaloid, filaments narrowly spatulate, slightly clawed, 13–21.3 × 2.9–6.8 mm, without anthers, second whorl with anthers;
anthers straight after dehiscence, epidermis smooth;
styles 8.9–15.2 mm.
cylindric, 13.6–23.5 × 5.1–7.8 mm, base tapering, not or slightly longitudinally ridged.
cylindric, 13.1–31.1 × 5.7–9.4 mm, base tapering to rounded, not longitudinally ridged.
coat anticlinal cell walls straight, papillae 4–17 per cell.
coat anticlinal cell walls wavy, papillae 4–13 per cell.
= 22.
= 18, 20.
Mentzelia albescens
Mentzelia speciosa
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.)
Mentzelia sinuata is treated here as a synonym of M. speciosa. The morphological characters previously used to differentiate these taxa are much more variable and overlapping than previous authors have identified, including within material from type populations. Although typical morphological forms of each taxon can be found, intermediate forms are found throughout the putative species’ highly overlapping ranges, often in a single population. The main character used to differentiate the two species has been chromosome number, with M. sinuata having 2n = 18 and M. speciosa having 2n = 20. Until a cytological study is conducted on populations throughout the range, M. speciosa is regarded as a single species that contains two chromosomal lineages.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
KS Wildflowers
MO Plants
WildflowerSearch
iNaturalist
USDA Plants Database
