Trifolium barbigerum |
Trifolium sonorense |
|
---|---|---|
bearded clover |
Sonoran clover |
|
Habit | Herbs annual, 7–20 cm, puberulent or glabrous. | Herbs perennial, 25–38+ cm, pubescent. |
Stems | decumbent or erect, branched. |
prostrate, branched. |
Leaves | palmate; stipules ovate-lanceolate, 0.5–1.1 cm, margins toothed or lacerate, apex acute-acuminate; petiole 1–10 cm; petiolules to 0.5 mm; leaflets 3, blades oblanceolate or obovate, 1.5–2.5 × 0.4–0.7 cm, base cuneate, veins fine, thickened distally, margins ± serrate or entire, apex rounded or retuse, surfaces pubescent or glabrous. |
palmate; stipules narrowly triangular, 0.7–1.7 cm, margins entire or finely serrulate, apex usually acute or acuminate, sometimes 2-fid; petiole 0.3–5 cm; petiolules to 1 mm; leaflets 3, blades obovate to obcordate, 0.9–1.6 × 0.7–1.2 cm, base cuneate, veins moderately thickened, margins serrate to weakly so, apex rounded or emarginate, mucronulate, surfaces slightly hairy abaxially, glabrous adaxially. |
Inflorescences | axillary or terminal, 5–20-flowered, subglobose or globose, 0.6–1.5 × 1–1.5 cm; involucres bowl-shaped, 5–15 mm, lobes 6–10, sharply setaceous-toothed, sinuses shallow. |
axillary, 10–20-flowered, depressed-globose or globose, 0.8–1.6 × 0.9–1.6 cm, rachis prolonged beyond flowers; involucres a narrow rim, or slightly proximally connate bracteoles of proximal flowers, 0.1–0.5 mm. |
Peduncles | 5–10 cm. |
2.8–5 cm. |
Pedicels | straight, 0.2 mm; bracteoles absent. |
reflexed in fruit, 1–3 mm; bracteoles linear-triangular, 0.5 mm. |
Flowers | 4–6 mm; calyx campanulate, 5–9 mm, usually pubescent, rarely glabrous, veins 5, tube 2–3 mm, lobes ± equal, setaceous, often exceeding banner, orifice open; corolla usually lavender to purple, usually with white tips, rarely wholly white, 5–8 mm, banner broadly oblong, proximally inflated in fruit, distally narrowed into twisted tip, 6–8 × 6–8 mm, apex broadly acute. |
5.7–6.7 mm; calyx tubular, 3.3–6.5 mm, pubescent, veins 10, tube 0.8–1 mm, lobes subequal, narrowly triangular, orifice open; corolla white or pink, 5.3–6.5 mm, banner obovate, 5.3–6.5 × 2.8–3.8 mm, apex broadly rounded or broadly acute. |
Legumes | ovoid-ellipsoid, 2–3 mm. |
obovoid, 4.3–4.4 mm. |
Seeds | 1 or 2, brown, ellipsoid to subglobose, 1–1.5 mm, slightly roughened. |
2, brownish orange or olive-brown, globose or broadly reniform, 1.2–1.7 mm, smooth. |
2n | = 16. |
= 16. |
Trifolium barbigerum |
Trifolium sonorense |
|
Phenology | Flowering Apr–Jun. | Flowering Aug–Oct. |
Habitat | Vernal pools, stream banks, meadows, lawns. | Dry stream banks, grassy places. |
Elevation | 0–1300 m. (0–4300 ft.) | 1500–1800 m. (4900–5900 ft.) |
Distribution |
CA; OR
|
AZ; Mexico (Chihuahua, Jalisco, Sinaloa, Sonora) |
Discussion | Trifolium barbigerum is relatively common and widespread in California, and extends northward into Coos, Curry, and Jackson counties in Oregon. It is morphologically similar to T. physanthum of Chile, to which it is a sister species in phylogenetic studies (N. W. Ellison et al. 2006). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Trifolium sonorense has long been equated with T. amabile Kunth, from which T. K. Ahlquist (2012) and also Ahlquist & M. A. Vincent have shown it to be distinct by longer sepal lobes (more than 3 mm), keel petal claws (more than 1.7 mm), and filament tubes (more than 3.6 mm). Trifolium sonorense is known from western Mexico and southernmost Arizona (Cochise County), largely in the Sonoran Desert region, and in mountainous Jalisco. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 11. | FNA vol. 11. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | T. minutissimum | |
Name authority | Torrey in War Department [U.S.]: Pacif. Railr. Rep. 4(5): 79. (1857) | T. K. Ahlquist & Vincent: Phytoneuron 2018-1: 1, fig. 1. (2018) |
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