Trifolium retusum L.
Annual; stems glabrous, procumbent or ascending, not rooting at nodes. Lvs glabrous; petioles c. 10-40 mm long; leaflets obovate, mostly acute and mucronate, cuneate at base, finely serrate, c. 5-15 mm long; lateral veins somewhat recurved and thickened toward leaflet margin; petiolules < 1 mm long, ± equal; stipules ovate, acuminate. Infls axillary, racemose, globose, pedunculate, usually < subtending lf, sometimes ± = lf, the upper often subsessile; peduncles 0.75-1 mm diam.; fls numerous, somewhat recurved at fruiting; pedicel up to 1 mm long but fls usually subsessile; bracts subtending fls free. Calyx ± glabrous or with a few scattered hairs, 10-veined, not inflated at fruiting; throat open, glabrous; calyx teeth unequal, narrowly triangular, recurved at fruiting but not flowering; upper 2 teeth longer, ± = corolla, = or > tube; sinuses acute. Corolla white or pink, persistent, 4-5 mm long. Pod glabrous, straight, < calyx, 2-3 mm long, 2-seeded; seeds c. 1 mm diam.
S.: known from 2 sites only, Wairau Bar (Marlborough) and Bannockburn (Otago).
C. and S.E. Europe to Caucasia, N. Africa 1976
Dry stony areas and sandy soil, pasture.
FL Oct.
T. retusum is similar to T. cernuum, but is distinguished by the more erect habit and denser flowering heads. T. retusum also resembles forms of T. glomeratum with shortly pedunculate heads, but is distinguished by the unequal and longer calyx teeth. The name T. parviflorum is usually regarded as a synonym of T. retusum although in N.Z. it has been misapplied to T. cernuum.
