Flora of North America species comparison

erect to ascending, branched.

pinnate;

stipules ovate-lanceolate, 0.5–0.8 cm, margins entire, glandular, apex acuminate;

petiole 0.3–2 cm;

lateral leaflet petiolules 0.5–0.6 mm, terminal leaflet stalk 3–5 mm;

leaflets 3, blades rhombic to obovate, 0.4–1.5 × 0.4–0.8 cm, base cuneate, lateral veins prominent, ± parallel, ascending, margins denticulate distally, apex truncate or retuse, surfaces strigose adaxially.

axillary, 30–60-flowered, globose or broadly ovoid, 0.8–1.5 × 0.7–1 cm;

involucres absent.

1.5–3.5 cm.

reflexed, 0.7–1.2 mm;

bracteoles a fringe of red setae.

4.3–5 mm;

calyx campanulate, strongly bilabiate, 1.3–1.5 mm, glabrous, veins 5, tube 0.3–0.6 mm, lobes unequal, adaxial deltate, very short, lateral and abaxial linear-subulate, each tipped with 1 or 2 stiff hairs, orifice open;

corolla yellow becoming brown, 3.5–6 mm, ribbed, banner persistent, obovate, enveloping other petals, boat-shaped, 4.3–5 × 2.8–3.2 mm, apex broad, acute.

stipitate, oblong, 2–2.5 mm.

1 or 2, yellow, ellipsoid, 1–1.5 mm, smooth, lustrous.

difficulty of distinguishing Trifolium mucronatum from T. wormskioldii is discussed under 33. T. wormskioldii.

in the United States represent T. mucronatum subsp. lacerum; in Mexico, subsp. lacerum is found in the north, subsp. mucronatum (petals pink or reddish, flowers 1.5–1.7 cm, inflorescences 2.5–3.5 cm diam.) is widespread, and subsp. vaughanae J.

.;

m .

(petals lavender or white, flowers 1.2–1.4 cm, inflorescences 1.5–2 cm diam.) is restricted to central Mexico (Guanajuato, San Luis Potosí) (J.; gillett 1980).

= 14.