Mentzelia aspera |
Mentzelia asperula |
|
---|---|---|
dal-pega, rough stickleaf, tropical blazingstar, tropical stickleaf |
mountain stickleaf, Organ Mountain blazingstar |
|
Habit | Plants annual, without caudices or tubers. | Plants annual, without caudices or tubers. |
Stems | erect to decumbent, to 30 cm. |
erect, to 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 to 12 mm (proximal leaves), absent (distal leaves); blade usually ovate to hastate, or smallest distal elliptic or lanceolate, basally lobed or unlobed, to 4.5 × 3.5 cm, base cuneate or obtuse to truncate, margins serrate, apex acute. |
Pedicels | (fruiting) 1–3 × 2 mm (often appearing absent because thick and continuous with capsule). |
(fruiting) 1–3 × 2 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 orange, 5–8 × 3–5 mm, apex cuspidate, hairy abaxially at apex; stamens 10–20, 5–8 mm, filaments monomorphic, filiform; style 3–5 mm. |
Capsules | subcylindric to clavate, 9–30 × 3–3.5 mm, base tapering gradually, capsule and pedicel not well-differentiated. |
subcylindric to clavate, 12–25 × 3–5 mm, base tapering gradually, capsule and pedicel not well-differentiated. |
Seeds | 5–9 per capsule, pyriform to oblong, without transverse folds. |
(7–)8–10(–12) per capsule, pyriform, without transverse folds. |
2n | = 20. |
= 20, 40. |
Mentzelia aspera |
Mentzelia asperula |
|
Phenology | Flowering Aug–Oct. | Flowering Aug–Oct. |
Habitat | Arroyo and canyon bottoms, grasslands, desert scrub, riparian cottonwood and willow vegetation. | Rocky limestone or igneous slopes, arroyo bottoms, grasslands, oak woodlands. |
Elevation | 100–2000 m. (300–6600 ft.) | 0–1800 m. (0–5900 ft.) |
Distribution |
AZ; Mexico; Central America; South America; West Indies [Introduced in Atlantic Islands (Cape Verde Islands)]
|
AZ; NM; TX; n Mexico; c Mexico
|
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.) |
Populations consistent with the form and geographic region of the type specimen of Mentzelia asperula (collected in southwestern New Mexico) have been recovered in two clades of sect. Mentzelia. In one clade, M. asperula is closely related to M. isolata; in the second clade, it is closely related to M. gypsophila B. L. Turner of northern Mexico (J. Grissom 2014). The polyphyly of M. asperula likely represents convergence on rapid developmental times and small, self-fertilizing flowers. In southeastern Arizona, M. asperula can be difficult to distinguish from M. isolata; see the discussion of the latter for more information. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 528. | FNA vol. 12, p. 528. |
Parent taxa | Loasaceae > Mentzelia > sect. Mentzelia | Loasaceae > Mentzelia > sect. Mentzelia |
Sibling taxa | ||
Name authority | Linnaeus: Sp. Pl. 1: 516. (1753) | Wooton & Standley: Contr. U.S. Natl. Herb. 16: 148. (1913) |
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