Diptychandra

Taxonomy

Diptychandra E.L.R. Tulasne Ann. Sci. Nat. Bot. ser. 2. 20: 139. Sep 1843.

Subfamily: Caesalpinioideae.
Phylogenetic Number: 1.1.05.
Tribe: Caesalpinieae.
Group: Sclerolobium.
Species Studied - Species in Genus: 3 studied; 3 in genus.

Description

Fruit: A legume; unilocular; 7.5–10 cm long; 2.5–3.5 cm wide; 0.3–0.4 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; not plicate; not twisted; symmetrical, or asymmetrical; elliptic; with 1 straight and 1 curved suture; widest near middle or D-shaped; not inflated; compressed; without beak; tapered at apex; aligned with longitudinal axis of fruit; tapered at base; oblique with longitudinal axis of fruit; with the apex and base uniform in texture; coriaceous; seed chambers externally invisible; margin constricted, or not constricted; margin slightly constricted along both margins; margin without sulcus; margin plain; wing(s) absent; substipitate; with all layers dehiscing; splitting along suture(s). Dehiscence of valves along both sutures; passive. Replum invisible. Epicarp dull; monochrome; brown; with surface texture uniform; glabrous; eglandular; without spines; not smooth; with elevated features; veined; reticulately veined; not tuberculate; not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; surface not veined; 1-layered; without balsamic vesicles; without fibers; without reniform canals; solid; coriaceous. Endocarp present; visible; dull; opaque; monochrome; brown; without adhering pieces of testa; nonseptate; not exfoliating; remaining fused to mesocarp and epicarp; entire. Seed(s) 1–3; length parallel with fruit length, or transverse to fruit length (parallel by length but transverse by embryonic axis); neither overlapping nor touching; in 1 series. Funiculus 0.1–1.5 mm long; of 1 length only; filiform; straight. Aril absent.

Seed: 35–65 mm long; 25–30 mm wide; 1–2 mm thick; not overgrown; not angular; symmetrical; oblong; flattened; 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; bichrome; brown (dark); glabrous; smooth, or not smooth; with elevated features; rugose and shagreen; chartaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) present (to 15 mm). Raphe not visible. Hilum present; fully concealed; concealed by funicular remnant; without faboid split; punctiform; apical according to radicle tip but marginal according to seed length; flush; not within corona, halo, or rim. Lens not discernible. 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; 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

Generic Notes

Winged seeds in the Fabaceae are restricted to this subfamily, To Diptychandra and Campsiandra (3.1.12), and to eight genera in the subfamily Mimosoideae. Diptychandra is being revised by de Lima and de Carvalho (Lewis, pers. commun., 1988).