Mentzelia filifolia

Plants biennial, candelabra-form. Stems solitary, erect, straight; branches distal, distal longest, antrorse, straight; hairy. Leaves: blade 43–94(–115) × (4.3–)7.5–36 mm, widest intersinus distance 1–2.4 mm; proximal oblanceolate to elliptic, margins pinnatisect, lobes 8–20, perpendicular to leaf axis, 3.2–12(–15.7) mm; distal oblanceolate to elliptic, base not clasping, margins pinnatisect, lobes 8–20, perpendicular to leaf axis, 5.6–17.1 mm; abaxial surface with simple grappling-hook, complex grappling-hook, and occasionally needlelike trichomes, adaxial surface with needlelike trichomes. Bracts: margins entire or pinnate. Flowers: petals golden yellow, 13–18.5 × 3.7–6.1 mm, apex acute, glabrous abaxially; stamens golden yellow, 5 outermost petaloid, filaments narrowly spatulate, slightly clawed, 10.2–14.7(–18) × (1.3–)2.5–4.4 mm, without anthers, second whorl with anthers; anthers straight after dehiscence, epidermis smooth; styles 10–12.5(–14) mm. Capsules cylindric, 11–19 × 5–7.5 mm, base tapering, not or diminutively longitudinally ridged. Seeds: coat anticlinal cell walls sinuous, papillae 42–48 per cell. 2n = 20.

Phenology: Flowering Jul–Aug.
Habitat: Roadcuts, slopes, dark loam, rocky soils.
Elevation: 2100–2200 m.

Distribution

• Generated Map
• Legacy Map

Ariz., N.Mex.

Discussion

Mentzelia filifolia is known from the Chuska Mountains of Apache County, Arizona, and McKinley and San Juan counties, New Mexico.

Selected References

None.

Lower Taxa

None.