Dolichos

Taxonomy

Dolichos C. Linnaeus Nom. cons. Sp. Pl. 725. 1 Mai 1753.

Subfamily: Faboideae.
Phylogenetic Number: 3.10.64.
Tribe: Phaseoleae.
Subtribe: Phaseolinae.
Species Studied - Species in Genus: 12 studied; 60 in genus.

Description

Fruit: A legume; unilocular; 1.5–7 cm long; 0.6–1.4 cm wide; 2–9 times longer than wide; with persistent androecial sheath, or deciduous androecial sheath; with deciduous corolla; with persistent calyx; with calyx shorter than fruit; without orifice formed by curving of fruit or fruit segments; straight; not plicate; not twisted; asymmetrical, or symmetrical; linear, or falcate; with 1 straight and 1 curved suture, or both sutures parallelly curved; widest near middle or D-shaped; not inflated; compressed; with beak; declined; with solid beak the same color and texture as fruit; tapered at apex, or short tapered at apex; aligned with longitudinal axis of fruit, or oblique with longitudinal axis of fruit; short tapered at base, or rounded at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; coriaceous, or leathery; seed chambers externally invisible; margin not constricted; margin without sulcus; margin plain, or embellished; margin with thickened sutural areas; wing(s) absent; nonstipitate; with all layers dehiscing; splitting along suture(s). Dehiscence of valves along both sutures; apical and down; active; with valves twisting. Replum invisible. Epicarp dull; monochrome; brown to tan; with surface texture uniform; glabrous, or pubescent and indurate; with hairs erect; with 1 type of pubescence; pilose, or puberulent; with pubescence golden; with simple hairs; pliable; with hair bases plain; eglandular; without spines; smooth, or not smooth; with elevated features; not veined; not tuberculate; wrinkled; not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; thick, or thin; surface not veined; 1-layered, or 2-layered; without balsamic vesicles; without fibers; without reniform canals; solid; with vitriol layer over solid layer; coriaceous. Endocarp present; visible; dull; opaque; monochrome; brown to tan; smooth; without adhering pieces of testa; septate; with septa thin (tissue paper-like), flexible, or thicker than paper, firm; with septa eglandular; chartaceous; not exfoliating; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) 2–11; length parallel with fruit length, or transverse to fruit length; neither overlapping nor touching; in 1 series. Funiculus 0.5–1 mm long; of 1 length only; flattened; triangular. Aril present; fleshy, or dry; when fleshy hippocrepiform rim-aril; entire; covering less than 1/2 of seed; when dry 2-lipped rim-aril; entire; covering less than 1/2 of seed; with tongues (or flap) on lips of 2-lipped rim-aril; with 1 tongue or flap on 1 lip of 2-lipped rim-aril; cream.

Seed: 3.3–9.5 mm long; 3–6.1 mm wide; 2–5 mm thick; not overgrown; angular, or not angular; symmetrical, or asymmetrical; circular to elliptic to irregular to reniform; terete to compressed; with surface smooth; without visible radicle and cotyledon lobes, or with visible radicle and cotyledon lobes; without external groove between radicle and cotyledon lobes; without hilar sinus; without umbo on seed faces; without medial ridge on each face. Cuticle not exfoliating; not inflated; not wrinkled. Testa present; without pieces of adhering epicarp; not adhering to endocarp; free from endocarp; glossy to dull; not modified by a bloom; colored; monochrome, or mottled; with frequent mottles; black to brown; with brown overlay (darker); glabrous; smooth, or not smooth; with elevated features; wrinkled; chartaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe barely visible, or not visible; from hilum through lens to base of seed and terminating; not bifurcating; darker than testa; dark brown; flush, or raised (slightly). Hilum present; visible, or partially concealed; concealed by aril; with faboid split; with the lips of the faboid split the same color as the rest of the hilum; larger than punctiform; 1.8–5 mm long; with curved outline to straight outline; narrowly elliptic, or oval (narrowly); linear; apical according to radicle tip but marginal according to seed length; flush; within corona, or not within corona, halo, or rim; corona color darker than testa. Lens discernible; 0.5–1.4 mm long; with margins straight; linear; not in groove of raphe, or in groove of raphe; confluent with hilum; flush; similar color as testa; darker than testa; black to brown; within rim, or within corona; corona color darker than testa; rim color of testa. Endosperm apparently absent. Cotyledons smooth, or not smooth; wrinkled; both outer faces convex; both the same thickness; both more or less of equal length; not folded; margin entire 180 degrees from base of radicle; similar at apex; partially concealing radicle, or not concealing radicle; notched at radicle; without lobes; with the interface division terminating at base of radicle; without margins recessed; white to yellow to tan (pale); inner face flat; glabrous on inner face. Embryonic axis oblique, or right angled; oblique to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; bulbose, or triangular; lobe tip straight; oblique to cotyledons; centered between cotyledons; less than 1/2 length of cotyledons. Plumule moderately developed to well developed; glabrous.

Distribution

Africa and eastern Asia.

Old World; Southwest Asia, Japan, Africa, Madagascar, India, Indochina, China, and Macaronesia.

Generic Notes

Dioclea multiflora (J. Torrey & A. Gray) C.T. Mohr has been placed in the genera Dolichos and Galactia (3.10.27) at different times (Maxwell 1979), and Fortunato, de Queiroz and Lewis segrated it as the monotypic genus Lackeya (3.10.27A), L. multiflora (J. Torrey & A. Gray) R.H. Fortunato, L.P. de Queiroz & G.P. Lewis (Fortunato et al., 1996), which we are accepting as a good genus. Few Dolichos fruits were studied.

Tribal Notes

Tribe Phaseoleae

Bruneau et al. (1995) carried out cladistic analyses of tribe Phaseoleae using chloroplast DNA restriction site data. Their results indicated that the tribe is not monophyletic and that the tribal delimitations between Phaseoleae and Desmodieae (11) and between Phaseoleae and Millettieae (7) are problematic.