1. Ammopiptanthus mongolicus (Maximowicz ex Komarov) S. H. Cheng, Bot. Zhurn. (Moscow & Leningrad). 44: 1381. 1959.
沙冬青 sha dong qing
Piptanthus mongolicus Maximowicz ex Komarov, Trudy Glavn. Bot. Sada 34: 33. 1920; Ammopiptanthus nanus (Popov) S. H. Cheng; P. nanus Popov.
Evergreen shrubs, 1.5-2 m tall; bark yellowish brown. Stems terete, weakly ridged, gray puberulent at first, glabrescent. Leaves 1- or 3-foliolate; stipules small, triangular, adnate to petiole, silvery tomentose; petiole 4-15 mm; leaflets rhombic-elliptic or broadly elliptic to broadly ovate, 1.5-4 × 0.6-2.4 cm, densely silvery tomentose on both surfaces, lateral veins inconspicuous, base broadly cuneate to rounded, apex obtuse, often mucronate. Flowers 4-15, in short dense terminal racemes; bracts ovate, 5-6 mm, deciduous; pedicels ca. 1 cm, subglabrous, with 2 bracteoles at midpoint. Calyx 5-7 mm. Corolla yellow, ca. 2 cm, petals long clawed. Ovary stipitate, glabrous. Legume linear-oblong, 3-8 × 1-2 cm, flat, apex acute to obtuse; stipe 8-10 mm. Seeds 2-5, orbicular-reniform, ca. 6 mm in diam. Fl. Apr-Jun, fr. May-Aug.
Sand dunes, gravel slopes, terraces beside ravines. Gansu, Nei Mongol, Ningxia, W Xinjiang (Kashi) [Kazakhstan, Kyrgyzstan, S Mongolia].
Two species have been recognized, but the differences between them are of degree only and do not appear to merit recognition of more than one rather variable species. Many species of arid areas vary considerably in their morphology according to water availability, grazing, and season, and this species appears to be no exception.