Astragalus lentiginosus var. wahweapensis |
Astragalus lentiginosus var. mokiacensis |
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wahweap freckled milkvetch |
mokiak milkvetch |
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Habit | Plants perennial (short-lived, sometimes flowering first year), 10–25(–35) cm. | Plants perennial, 20–60 cm, herbage green or subglabrescent. |
Stems | diffuse and incurved-ascending. |
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Leaves | (2.5–)4–11 cm; leaflets 13–23, blades elliptic-oblanceolate, broadly oblong-oblanceolate, or obovate, (3–)5–17(–20) mm, apex obtuse or emarginate. |
3–10(–13) cm; leaflets (7 or)9–17(–21), blades broadly obovate-obcordate, lanceolate, elliptic, or suborbiculate-obcordate, 5–13(–19) mm, apex emarginate or retuse to truncate, adaxial surface glabrous. |
Racemes | 10–20-flowered, flowering from middle and distally, compact to loose in fruit; axis 1.5–5.5(–7) cm in fruit. |
loosely 12–20-flowered; axis elongating, 3.5–18(–22) cm in fruit. |
Peduncles | 2.5–6(–7.5) cm. |
4–11(–14) cm. |
Flowers | (12.5–)15–18.2 mm; calyx (6.2–)7.5–10.5 mm, tube (4.6–)5.2–6.7 mm, lobes 1.4–3.8 mm; corolla usually bright pink-purple with pale, striate eye, rarely white (concolorous). |
(10–)14–18(–19) mm; calyx 5–8(–9.2) mm, tube (3.5–)4–6.5 mm, lobes 1–2(–2.7) mm; corolla pink- to red-purple, usually with pale or white wing tips. |
Legumes | green, sometimes stramineous or purple-mottled, almost always very strongly incurved, very obliquely ovoid-acuminate, moderately or greatly inflated, 15–30(–40) × (7–)9–15 mm, bilocular, thinly papery, semitranslucent, seeds visible, to almost leathery, opaque, usually glabrous, rarely puberulent; beak well-defined, triangular or deltoid, 6–15 mm, unilocular. |
dehiscent on plant, usually ascending-erect to ascending, rarely spreading, green becoming stramineous, usually ± straight to incurved, rarely decurved, oblong-ellipsoid, not or scarcely inflated, slightly turgid, 14–28(–32) × 4.5–6.5 mm, ± bilocular, somewhat fleshy becoming leathery or stiffly papery, glabrous or minutely pubescent; beak 3–4 mm, unilocular. |
Seeds | (20–)24–28. |
(22–)25–36. |
2n | = 22. |
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Astragalus lentiginosus var. wahweapensis |
Astragalus lentiginosus var. mokiacensis |
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Phenology | Flowering Apr–Jul. | Flowering Mar–Jun. |
Habitat | Pinyon-juniper, sagebrush, and mixed desert shrub communities. | Limestone on outcrops and gravel, on basaltic or granitic gravel and/or outcrops, with Hymenoclea, bursage, Joshua tree, Larrea, and Ferocactus. |
Elevation | 1400–1900 m. (4600–6200 ft.) | 700–1800 m. (2300–5900 ft.) |
Distribution |
AZ; UT |
AZ; NV; UT |
Discussion | Variety wahweapensis may be very abundant in wetter years, filling the interspaces in pinyon-juniper woodland much like an alfalfa field. It is found on the plateaus and drainages affluent to Lake Powell in eastern Kane and Garfield counties in Utah, and in northern Arizona. Variety wahweapensis grades into the slender-podded var. palans to the east and the ovoid-fruited var. diphysus southward. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
The placement of var. mokiacensis has challenged generations of botanists. R. C. Barneby (1945) regarded var. mokiacensis as part of the lentiginosus complex but later (Barneby 1964) recognized it as a species within sect. Preussiani. In Washington County in Utah, var. mokiacensis has been consistently confused with var. palans. S. L. Welsh (2007) extensively discussed problems revolving around interpretation and distinction of var. mokiacensis. J. A. Alexander (2005) considered the taxon to be best recognized at the species level, as A. mokiacensis, the persistent fruit being otherwise unknown in A. lentiginosus. Alexander also presented a key to similar taxa and to minor variants within A. mokiacensis. As recognized here, the variety is found in Washington County in southwestern Utah, northwestern Mohave County in Arizona, and eastern Clark County in Nevada. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 11. | FNA vol. 11. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | A. mokiacensis, A. lentiginosus var. ursinus | |
Name authority | S. L. Welsh: Great Basin Naturalist 38: 286. (1978) | (A. Gray) M. E. Jones: Rev. N.-Amer. Astragalus, 126. (1923) |
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