5. Nanhaia J.Compton & Schrire gen. nov.

≡ Millettia Sect. Corynecarpae Z.Wei, Acta Phytotax. Sin. 23(4): 281 (1985)

Diagnosis.

Nanhaia, with two species, is readily distinguished from Wisteriopsis by the densely pubescent or sericeous ovaries (glabrous in Wisteriopsis) and the larger flowers frequently 15-35 mm long (vs Wisteriopsis 7-15 mm long). In Nanhaia the stipules arise immediately above the swollen, hardened gibbosities (Fig. 4).

Type species.

Nanhaia speciosa (Champ. ex Benth.) J.Compton & Schrire ≡ Millettia speciosa Champ. ex Benth.

Genus description.

Procumbent or scandent twining vines, 1-5 m high, scrambling among rocks and scrub. Stems green or brown, terete, pubescent. Leaves with 5-17 leaflets, evergreen, glabrous or with a few scattered hairs below, imparipinnate, rachis 3-30 cm long. Stipules 2-4 mm long, linear or deltoid, caducous in N. fordii (persistent N. speciosa). Stipels 1-3 mm long, linear, persistent. Leaflets 3-9 × 1-4 cm, ovate-elliptic or narrowly elliptic, glabrescent or sparsely hairy, apex acuminate or cuspidate, margins entire, base rounded to subcordate. Inflorescence erect or pendant sometimes leafy panicles 4-20 cm long, frequently comprising several leafy lateral racemes, peduncle yellow tomentose or densely brown pubescent. Flowers 16-32 mm long, emerging from June to September. Floral bracts 3-7 mm long, linear or narrowly deltoid, persistent (caducous in N. fordii). Bracteoles at base of calyx 1-5 mm long, narrowly ovate or elliptic, persistent. Pedicels 4-11 mm long, glabrous or pubescent. Calyx 4-6 × 5-9 mm campanulate, oblique, pubescent externally, (densely pubescent internally on N. fordii) five lobed, teeth unequal, 1-3 mm long, acute. Standard 12-18 × 11-18 mm, suborbicular, white, cream or pink, nectar guide pale or dark green, back of standard glabrous, apex acute or obtuse. Callosities of boss type. Wing petals 12-17 × 4-6 mm, glabrous, subequal to the keel, each narrowly semi-pandurate, slightly curved upwards at the apex; free from the keel, apex obtuse, basal claws 2-5 mm long. Keel petals 12-16 × 4-6 mm, glabrous, united into a falcate, navicular cup, apex obtuse, basal claw 4-9 mm long. Stamens diadelphous, nine fused together, the vexillary one free, all curved upwards at apex. Ovary densely sericeous, especially along thickened margins, style ciliate ( N. speciosa) or glabrous ( N. fordii), 2-3 mm long curved upwards at apex, stigma punctate. Pods 10-20 × 1-2 cm, flat, linear, dehiscent, surface pubescent to densely brown tomentose, brown and hard when dry, subseptate. Seeds 2-10, ovoid or ellipsoid, 10-12 × 5-12 × 1-7 mm, hilum terminal or central, elliptic, 2-3 × 1 mm. Fig. 4.

Distribution.

China (Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hunan, Yunnan); Vietnam (north).

Etymology.

Nanhai is the Chinese name for the South China Sea which links southern China with Vietnam.