Dinizia

Taxonomy

Dinizia W.A. Ducke Arch. Jard. Bot. Rio de Janeiro 3: 76. 1922.

Subfamily: Mimosoideae.
Phylogenetic Number: 2.3.01.
Tribe: Mimoseae.
Group: Dinizia.
Species Studied - Species in Genus: 1 studied; 1 in genus.

Description

Fruit: A legume; unilocular; 15–35 cm long; 5–7 cm wide; 0.1–0.5 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 to curved; not plicate; not twisted; symmetrical; broadly oblong; not inflated; flattened; without beak; short tapered at apex; aligned with longitudinal axis of fruit; tapered at base to rounded at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; coriaceous; seed chambers externally faintly visible; margin not constricted; margin without sulcus; margin plain; wing(s) absent; stipitate; with the stipe up to 25 mm long; indehiscent. Replum invisible. Epicarp glossy; monochrome; brown (to blackish brown); with surface texture uniform; glabrous; eglandular; without spines; not smooth; with elevated features; faintly veined; reticulately veined; not tuberculate; prominent longitudinally wrinkled (paralleling both margins); not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp absent. Endocarp present; visible; dull; opaque; monochrome; tan; smooth; without adhering pieces of testa; nonseptate (though seed chambers fringed by spongy tissue); not exfoliating; entire. Seed(s) 5–10; length transverse to fruit length; neither overlapping nor touching; in 1 series. Funiculus to 13 mm long; of 1 length only; filiform; S-curved. Aril absent.

Seed: 10–13 mm long; 6–7 mm wide; 1.5 mm thick; not overgrown; not angular; symmetrical; oblong; 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; not modified by a bloom; colored; monochrome; black; glabrous; not smooth; with recessed features; faintly, parallel striate (testa splitting along striations during imbibition); chartaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe not visible. Hilum present; visible, or fully concealed; concealed by funicular remnant; without faboid split; punctiform; apical at apex of radicle tip; recessed; not within corona, halo, or rim. Lens not discernible. Endosperm present; thick; not pluglike and not resembling tip of radicle; covering entire embryo; adnate to embryo (masking true position of radicle). 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; with lobes; with lobes not touching; with the interface division terminating at base of radicle; without margins recessed; inner face flat; glabrous on inner face. Embryonic axis straight; parallel to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; straight with embryonic axis; centered between cotyledons. Plumule rudimentary; glabrous.

Distribution

Brazil and Guyana.

New World; South America (Brazil and Guyana); Brazil and Ecuador.

Generic Notes

More seeds and fruits should be collected and distributed to herbaria, Because mature seeds are seldom found in the collected fruits. Fruit and seed characters confirm the decision of Elias (1981) not to place this genus in the Mimozygantheae.