Mentzelia albescens
Mentzelia ravenii
wavy-leaf blazingstar
grass blazingstar, Raven's blazingstar
solitary, erect, straight;
branches distal, distal longest, antrorse, straight; 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.
persisting;
petiole present or absent;
blade linear-lanceolate, margins deeply to shallowly lobed.
petiole absent;
blade ovate-lanceolate to lanceolate, to 18 cm, margins deeply lobed to dentate.
margins entire.
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.
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.
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.
cylindric, 13.6–23.5 × 5.1–7.8 mm, base tapering, not or slightly longitudinally ridged.
clavate, 8–23 × 2–3 mm, axillary curved to 45° at maturity, usually inconspicuously longitudinally ribbed.
coat anticlinal cell walls straight, papillae 4–17 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.
= 22.
= 36.
Mentzelia albescens
Mentzelia ravenii
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 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.)
KS Wildflowers
MO Plants
WildflowerSearch
iNaturalist
USDA Plants Database
CA
