Nesphostylis Verdc.

Legumes of the World. Edited by G. Lewis, B. Schrire, B. MacKinder & M. Lock. Royal Botanic Gardens, Kew. (2005)

Note

Previous accounts of the Phaseoleae by Baudet (1978) and Lackey (1981) recognised 90 and 84 genera and c. 1540 and 1480 species respectively in the tribe. In an equivalent, i.e. traditionally held view of Phaseoleae, 89 genera and (1554)–1567–(1580) species are treated here (Table 9; Fig. 47). Changes between Baudet (1978) and this treatment are that eleven genera are now in synonymy or have subsequently been placed in Millettieae, two genera have been transferred from Desmodieae and eight new genera have been added. Vigna has traditionally been thought to comprise some 150–200 species, but Vigna sens. strict. may contain fewer than 100.

Recent molecular analyses of the tribe, however, have emphasised both the polyphyletic and paraphyletic nature of Phaseoleae as traditionally circumscribed (Bruneau & Doyle, 1990; Doyle & Doyle, 1993; Delgado Salinas et al., 1993; Bruneau et al., 1995; Doyle et al., 1997, 2000; Kajita et al., 2001; Goel et al., 2001; Lee & Hymowitz, 2001). This has required a radical realignment of elements of the phaseoloids (Table 9; Fig. 47), with at least two major clades being evident: Phaseoleae subtribes Diocleinae and Ophrestiinae which together with tribe Abreae are allied to the core-Millettieae (Fig. 45), and the remaining groups comprising a Phaseoleae sens. lat. clade. The rbcL phylogeny of Kajita et al. (2001) and the ITS analysis of Hu et al. (2002) are equivocal as to which clade subtribe Clitoriinae belongs. Phaseoleae sens. lat. also includes two traditionally independent tribes, the Desmodieae and Psoraleeae. Delimiting a recircumscribed Phaseoleae sens. strict is thus very problematic. A solution may be to recognise a broad tribe Phaseoleae, comprising the subtribes Kennediinae, Cajaninae, Phaseolinae and Glycininae, assorted basally branching genera, and tribes Desmodieae and Psoraleeae (both treated at subtribal level).

Placed in subtribe Phaseolinae, allied to Dolichos (Thulin et al., 2004)

Habit

Herbs

Ecology

Seasonally dry tropical and subtropical woodland, wooded grassland and grassland

Distribution

Africa (Zambezian and Sudanian regions, 2 spp.); SE Asia (Indian subcontinent, Indo-China [Myanmar], 2 spp.)

Leguminosae, B. Mackinder, R. Pasquet, R. Polhill & B. Verdcourt. Flora Zambesiaca 3:5. 2001

Morphology General Habit

Perennial climbing herb.

Morphology Leaves

Leaves pinnately 3-foliolate; stipules small, striate; stipels present.

Morphology Reproductive morphology Inflorescences

Inflorescences axillary; flowers solitary.

Morphology Reproductive morphology Flowers Calyx

Calyx 5-lobed, but the upper lobes connate.

Morphology Reproductive morphology Flowers Corolla

Corolla large, blue or pale purple; standard glabrous, auriculate and with appendages at the base.

Morphology Reproductive morphology Flowers Androecium Stamens

Vexillary stamen free, with a tooth-like appendage at the base; filaments dilated at the apex; anthers similar in size, but 5 basifixed and 5 subdorsifixed.

Morphology Reproductive morphology Flowers Gynoecium Pistil

Ovary linear, many-ovuled; tomentose; style slightly twisted, flattening into a wedge shape at the apex, with a ring of hairs directly below the terminal stigma.

Morphology Reproductive morphology Fruits

Pods linear, compressed, many-seeded.

Morphology Reproductive morphology Seeds

Seeds oblong, with a well developed aril.