Cyamopsis

Taxonomy

Cyamopsis A.P. de Candolle Prodr. 2: 215. Nov (med.) 1825; 230. 1 Mar 1826. Nov (med.) 1825.

Subfamily: Faboideae.
Phylogenetic Number: 3.9.06.
Tribe: Indigofereae.
Species Studied - Species in Genus: 3 studied; 4 in genus.

Description

Fruit: A legume; unilocular; 3.5–5 cm long; 0.4–1.8 cm wide; 0.4–0.5 cm thick; 2–9 times longer than wide; with deciduous androecial sheath; with deciduous corolla; with deciduous calyx; without orifice formed by curving of fruit or fruit segments; straight (or nearly so); not plicate; not twisted; symmetrical; linear (to somewhat falcate); not inflated; compressed; with beak; straight; with solid beak the same color and texture as fruit; short tapered at apex; aligned with longitudinal axis of fruit; short tapered at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; coriaceous; seed chambers externally visible, or invisible; seed chambers with the raised seed chambers not torulose; margin not constricted; margin without sulcus; margin plain; wing(s) absent; nonstipitate; with all layers dehiscing; splitting along suture(s). Dehiscence of valves along both sutures; apical and down; passive. Replum invisible. Epicarp dull; monochrome; light to dark brown to tan to black; with surface texture uniform; pubescent and indurate; with hairs erect; with 1 type of pubescence; puberulent; with pubescence gray; with pubescence uniformly distributed; with complex hairs; with T-shaped hairs; pliable; with hair bases plain; eglandular; without spines; not smooth; with elevated features and recessed features; not veined; not tuberculate; wrinkled; longitudinally grooved; 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; tan; smooth; without adhering pieces of testa; septate; with septa thicker than paper, firm; with septa eglandular; chartaceous; not exfoliating; remaining fused to mesocarp and epicarp; without wings. Seed(s) 4–7; length parallel with fruit length; neither overlapping nor touching; in 1 series. Funiculus 0.5–1 mm long; of 1 length only; thick; straight. Aril present, or absent; dry; when dry tongue-aril; entire; tan.

Seed: 3–4 mm long; 3–3.4 mm wide; 1.8–2.8 mm thick; overgrown, 1 seed filling entire fruit cavity; angular to not angular; symmetrical, or asymmetrical; circular, or elliptic, or rectangular; compressed; with surface grooved; longitudinal and transverse (C. seneganlensis J.B.A. Guillemin & G.S. Perrottet); 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; dull; not modified by a bloom; colored, or clear (C. tetragonoloba); monochrome, or bichrome (brown and dark brown); black, or brown (greenish), or cream, or green, or tan, or yellow; glabrous; not smooth; with elevated features, or recessed features; shagreen; grooved (4 parallel grooves on each face of C. seneganlensis); coriaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe not visible. Hilum present; visible, or fully concealed; concealed by aril; with faboid split; with the lips of the faboid split the same color as the rest of the hilum; punctiform; marginal according to radicle tip; flush; not within corona, halo, or rim. Lens discernible, or not discernible; with margins curved; circular; not in groove of raphe; confluent with hilum; mounded; dissimilar color from testa; darker than testa; black; not within corona, halo, or rim. Endosperm present; thick; not pluglike and not resembling tip of radicle; covering entire embryo; adnate to embryo. Cotyledons smooth; both outer faces convex; both the same thickness; both more or less of equal length; with both folded; sufficiently folded for inner face to touch itself, or not sufficiently folded for inner face to touch itself (just base); portions of inner folded face unequal; margin entire 180 degrees from base of radicle; differing at apex (1 concealed by overarching radicle and other auriculate and concealing radicle); partially concealing radicle (depending on the cotyledon), or not concealing radicle (depending on the cotyledon); entire over radicle, or split over radicle; without lobes, or with lobes; with lobes not touching; without basal groin formed by lobes; with the interface division terminating at base of radicle; without margins recessed; tan; inner face flat; glabrous on inner face. Embryonic axis deflexed; oblique to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; linear; lobe tip straight; deflexed and parallel to cotyledon width; not centered between cotyledons (radicle outside 1 cotyledon and inside other, therefore junctions for each cotyledon different); 1/2 to nearly length of cotyledons. Plumule rudimentary; glabrous.

Distribution

Arabia and drier parts of Africa. Cyamopsis tetragonoloba is known only from cultivation, and was possibly Indian in origin.

Old World; Africa and Southwest Asia.

Worldwide crop (C. tetragonoloba).

Generic Notes

Unlike most faboid seeds soaked in Pohlstoffe for less than 24 hours, The testa of Cyamopsis species fragments as it does in Tripodion (19.02B).

Tribal Notes

Tribe Indigofereae

Schrire (1995) carried out extensive cladistic anaylses with Indigofereae genera and infrageneric taxa of Indigofera (9.07).