Subfamily: Faboideae.
Phylogenetic Number: 3.10.71.
Tribe: Phaseoleae.
Subtribe: Phaseolinae.
Species Studied - Species in Genus: 9 studied; 20 in genus.
Fruit: A legume; unilocular; 1.5–13 cm long; 0.3–0.6 cm wide; 0.3–0.5 cm thick; more than 9 times longer than wide; with 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, or curved (slightly); not plicate; not twisted; asymmetrical, or symmetrical; linear, or falcate; with both sutures parallelly curved; not inflated; compressed to terete; without beak; long tapered at apex to tapered at apex; aligned with longitudinal axis of fruit, or oblique with longitudinal axis of fruit; tapered at base to short tapered at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; chartaceous to coriaceous; seed chambers externally invisible; margin not constricted; margin without sulcus; margin plain, or embellished; margin with slightly 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, or green, or tan; with surface texture uniform; pubescent and indurate; with hairs erect, or appressed; with 1 type of pubescence, or 2 types of pubescence; pilose, or puberulent, or villous; with pubescence golden, or gray-brown, or white; with long and short white hairs intermixed; with pubescence uniformly distributed; with simple hairs; pliable; with hair bases plain; eglandular; without spines; smooth; not veined; not tuberculate; not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; thin; surface not veined; 1-layered; without balsamic vesicles; without reniform canals; solid; coriaceous to chartaceous. Endocarp present; visible; dull; opaque; monochrome; white; cobwebby to fibrous; without adhering pieces of testa; septate; with septa thin (tissue paper-like), flexible; with septa eglandular; chartaceous; not exfoliating; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) 1–27; length parallel with fruit length; neither overlapping nor touching; in 1 series. Funiculus 0.5 mm long; of 1 length only; flattened; triangular. Aril present; dry, or fleshy (rarely); when fleshy hippocrepiform rim-aril; crenate; covering 1/2 to nearly all of seed; when dry rim-aril, or 2-lipped rim-aril; entire; covering less than 1/2 of seed; without tongue (or flap) on lips of 2-lipped rim-aril; cream to white.
Seed: 3–7 mm long; 2–4.5 mm wide; 1.5–4 mm thick; not overgrown; angular, or not angular; symmetrical, or asymmetrical; irregular, or oblong, or ovate, or reniform; terete to compressed; with surface smooth; without visible 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, or modified by a bloom; colored; monochrome, or mottled; with frequent mottles; brown to black; with dark brown overlay to black overlay; glabrous; smooth; chartaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe not visible. 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; 1–4.2 mm long; with curved outline; elliptic, or oval; apical according to radicle tip but marginal according to seed length; recessed; within corona, or within corona and within halo; corona color darker than testa; halo lighter than testa. Lens discernible; 0.5–1 mm long; with margins straight; linear; not in groove of raphe; confluent with hilum; mounded; similar color as testa; darker than testa; brown; within rim, or not within corona, halo, or rim; rim color darker than testa. Endosperm absent. Cotyledons smooth; 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; notched at radicle; without lobes; with the interface division terminating at base of radicle; without margins recessed, or with margin(s) recessed; with 1 margin recessed; recessed on same side as radicle; yellowish white to white; inner face flat; glabrous on inner face. Embryonic axis oblique; perpendicular to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; linear; lobe tip curved; with 180 degree turn to oblique to cotyledons; centered between cotyledons; less than 1/2 length of cotyledons. Plumule moderately developed, or well developed; glabrous.
Macroptilium was treated for Brazil by Barbosa Fevereiro (1987). Underground fruits and seeds of M. gracile (E.F. Poeppig ex G. Bentham) I. Urban, M. heterophyllum (C.L. von Willdenow) R. Maréchal & J.C. Baudet, M. panduratum (C.F.P. von Martius ex G. Bentham) R. Maréchal & J.C. Baudet, and M. pedatum (J.N. Rose) R. Maréchal & J.C. Baudet were not available for study. Macroptilium atropurpureum (A. P. de Candolle) I. Urban, Sirato, is one of the most important tropical pasture legumes (Duke, 1981); it is very drought resistant.
Authors: J.H. Kirkbride, Jr., C.R. Gunn, A.L. Weitzman, M.J. Dallwitz, K.R. Thiele
Content last updated April 2003
Released April 2024 on idtools.org
