Galactia

Taxonomy

Galactia P. Browne Civ. Nat. Hist. Jamaica 298. 10 Mar 1756.

Subfamily: Faboideae.
Phylogenetic Number: 3.10.27.
Tribe: Phaseoleae.
Subtribe: Diocleinae.
Species Studied - Species in Genus: 18 studied; 50 in genus.

Description

Fruit: A legume; unilocular; 2.5–8 cm long; 0.4–1.2 cm wide; 0.1–0.3 cm thick; 2–9 times longer than wide; with persistent androecial sheath (with or without the keel), or deciduous androecial sheath; with persistent corolla (with or without androecial sheath), or deciduous corolla; with keel petal; with persistent calyx, or deciduous 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, or flattened; without beak; tapered at apex, or short tapered at apex; aligned with longitudinal axis of fruit, or oblique with longitudinal axis of fruit; tapered at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; chartaceous to coriaceous; seed chambers externally invisible, or visible; seed chambers with the raised seed chambers not torulose; margin not constricted; margin without sulcus; margin plain, or embellished; margin with thickened sutural areas (slightly); 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, or multicolored; mottled; brown; with brown overlay (darker); mottling color combination constant; with mottling over seed chambers; with surface texture uniform; pubescent and indurate, or pubescent but soon deciduous; with hairs erect; with 1 type of pubescence, or 2 types of pubescence; densely tomentose, or velutinous, or sericeous, or tomentose and villous; with pubescence white, or golden; 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 fibers; without reniform canals; solid; coriaceous. Endocarp present; visible; dull; opaque; monochrome; brown to tan; cracked; without adhering pieces of testa; subseptate; with septa thin (tissue paper-like), flexible; with septa eglandular; chartaceous; exfoliating; separating from mesocarp; without wings; entire. Seed(s) 5–10; length parallel with fruit length, or oblique to fruit length; neither overlapping nor touching; in 1 series. Funiculus 0.5–4 mm long; of 1 length only; filiform; curved, or triangular. Aril present; dry; when dry 2-lipped rim-aril; entire; covering less than 1/2 of seed; without tongue (or flap) on lips of 2-lipped rim-aril, or with tongues (or flap) on lips of 2-lipped rim-aril; with 2 tongues or flaps, 1 on each lip of 2-lipped rim-aril; tan.

Seed: 3.5–7.8 mm long; 2.6–4.5 mm wide; 1.7–3.7 mm thick; not overgrown; not angular; symmetrical, or asymmetrical; D-shaped, or elliptic, or ovate, or reniform; terete, or 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; dull; not modified by a bloom; colored; monochrome, or mottled; with frequent mottles, or infrequent mottles; brown, or orange (brownish), or tan; with brown overlay, or tan overlay; glabrous; smooth; chartaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe not visible. Hilum present; visible; with faboid split; with the lips of the faboid split the same color as the rest of the hilum; larger than punctiform; 1–4.5 mm long; with curved outline, or straight outline; elliptic; linear; apical according to radicle tip but marginal according to seed length; raised; within rim; rim color of testa, or darker than testa. Lens discernible; 0.5–0.7 mm long; with margins straight; linear; not in groove of raphe; confluent with hilum; flush; similar color as testa; darker than testa; brown, or red; within halo; halo color of testa, or darker than testa. Endosperm present; trace; not pluglike and not resembling tip of radicle; restricted to region of embryo; adnate to testa. 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, or not entire 180 degrees from base of radicle; slightly notched; similar at apex; partially concealing radicle; split over radicle; without lobes; with the interface division terminating at base of radicle; without margins recessed; white; inner face flat; glabrous on inner face. Embryonic axis right angled; oblique to length of seed, or perpendicular to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; linear, or triangular; lobe tip curved; oblique to cotyledons; centered between cotyledons; less than 1/2 length of cotyledons. Plumule well developed; glabrous.

Distribution

Pantropics, Pansubtropics, and temperate southern United States.

New World and Old World; pantropical to pansubtropical; United States, Mexico, Central America, and South America; Argentina, Peru, Brazil, Ecuador, and the Guianas; China, Japan, Africa, Madagascar, India, Indonesia and the Philippines, and Australia.

Generic Notes

Burkart (1971) monographed the Galactia species of South America.

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.