Afzelia 

Taxonomy

Afzelia J.E. Smith Nom. cons. Trans. Linn. Soc. London 4: 221. 1798.

Subfamily: Caesalpinioideae.
Phylogenetic Number: 1.4.20.
Tribe: Detarieae.
Group: Hymenostegia.
Species Studied - Species in Genus: 10 studied; 13 in genus.

Description

Fruit: A legume; unilocular; 7–30 cm long; 3–13 cm wide; 1–4 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 to curved; not plicate; not twisted; asymmetrical; nearly elliptic to oblong; not inflated; compressed; without beak; long tapered at apex; aligned with longitudinal axis of fruit to right-angled with longitudinal axis of fruit (sometimes with small beak); rounded at base; aligned with longitudinal axis of fruit to right angled with longitudinal axis of fruit; with the apex and base uniform in texture; ligneous; seed chambers externally visible, or invisible; margin constricted, or not constricted; margin slightly constricted along both margins; margin without sulcus; margin plain; wing(s) absent; stipitate; with the stipe 6–8 mm long; with all layers dehiscing; splitting along suture(s). Dehiscence of valves along 1 suture, or both sutures; passive. Replum invisible. Epicarp dull; monochrome; blackish to dirty brown; with surface texture uniform; glabrous; eglandular; without spines; not smooth; with elevated features; not veined; not tuberculate; transversely fibrous to faintly rugose; not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; surface not veined; 2-layered; without balsamic vesicles; with fibers; without reniform canals; with fibers transeverse over spongy tissue, or over solid layer (?); ligneous. Endocarp present; visible; dull; opaque; monochrome; whitish tan to tan; sometimes reddish brown scurfy; without adhering pieces of testa; septate to subseptate; not exfoliating; remaining fused to mesocarp and epicarp; entire. Seed(s) 1–12; length transverse to fruit length; neither overlapping nor touching; in 1 series. Funiculus 0.1–3 mm long; of 1 length only; flattened; straight. Aril present, or absent (orange, yellow, orange red, red yellow, whitish, or brown); fleshy (?); when fleshy caplike; entire; covering up to 1/2 to nearly all of seed.

Seed: 20–25 mm long; 9–29 mm wide; 5–22 mm thick; not overgrown; not angular; symmetrical; elliptic, or circular, or oblong; nearly terete; 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; in some speceis covered by endocarp which is reddish brown, or black; glabrous; not smooth; with elevated features; transversely reticulate; osseous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent (reticulate lines in testa, especially along margins, simulate fracutre lines). Rim absent. Wing(s) absent. Raphe not visible (raphelike depression on the faces of seeds is the depression caused by the junction of the two cotlyledons). Hilum present; fully concealed; concealed by usually aril; without faboid split; larger than punctiform; 0.1–3 mm long; with straight outline (with length at right angles to seed width and parallel to cotyledon junction); apical at apex of radicle tip; flush; not within corona, halo, or rim. Lens discernible, or not discernible; 0.1–1.3 mm long; with margins curved; circular; not in groove of raphe; mounded; same color as testa; not within corona, halo, or rim. 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; completely concealing radicle; notched at radicle and split over radicle (shallowly); with the interface division terminating at base of radicle; without margins recessed; inner face flat; glabrous on inner face. Embryonic axis straight; oblique to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; centered between cotyledons. Plumule rudimentary; glabrous.

Distribution

Burma to China, Malaysia, tropical Africa.

Old World; tropical Africa, Indochina, Indonesia and the Philippines, and China (and Malaysia).

Generic Notes

The transverse reticulation cracks in the testa, Especially along margins, create a type of fracture lines: Not the fracture lines of the Mimosoideae. The raphelike depression on the faces of seeds is the depression caused by the junction of the two cotyledons. Like Cassia (2.16) seeds, the seeds of Afzelia are dorsiventrally compressed, and this type of compression is rare in the Fabaceae. Seeds of fresh fruits are embedded in a white pith. The presence of a discernible lens may vary within a species. Léonard et al. (1952, fig. 30) illustrated seeds of six species. Seeds are often used for ornamental purposes and as a "charm in fight or to dispel evil, and avert injury by weapons, etc." (Dalziel, 1937).

Tribal Notes

Tribe Detarieae

Bruneau et al. (2000) carried out extensive phylogenetic analyses of tribes Amherstieae and Detarieae. They concluded that they form a single monophyletic group. Therefore, they supported Polhill's (1995a, 1995b) decision to unite the two tribes.