Haematoxylum

Taxonomy

Haematoxylum C. Linnaeus Sp. Pl. 384. 1 Mai 1753.

Subfamily: Caesalpinioideae.
Phylogenetic Number: 1.1.28.
Tribe: Caesalpinieae.
Group: Caesalpinia.
Species Studied - Species in Genus: 3 studied; 3 in genus.

Description

Fruit: A legume; unilocular; 2–4.5 cm long; 0.8–1.2 cm wide; 0.1 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; lanceolate, or oblong; not inflated; compressed; without beak; long tapered at apex to tapered at apex; aligned with longitudinal axis of fruit; short 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 invisible, or visible; margin constricted, or not constricted (not constricted in 1-seeded fruits); 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 apical and down to basal and up (along facial line and not the suture). Replum invisible. Epicarp dull; monochrome; reddish brown to purple; with surface texture uniform; glabrous, or glabrate (glabrous in American spp.); with hairs erect; glandular; with glandular hairs (in African spp.); 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, or tan; without adhering pieces of testa; nonseptate; not exfoliating; remaining fused to mesocarp and epicarp; entire. Seed(s) 1–3; length parallel with fruit length; neither overlapping nor touching; in 1 series. Funiculus 0.1–4 mm long; of 1 length only; thick; straight, or curved (sharply bent). Aril absent.

Seed: 5–12 mm long; 3–5 mm wide; 1 mm thick; not overgrown; not angular; symmetrical, or asymmetrical; oblong, or reniform; 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; monochrome, or bichrome; yellowish and streaked reddish brown; glabrous; smooth; osseous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. 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; recessed; not within corona, halo, or rim. Lens discernible; 0.5 mm long; with margins straight; triangular; not in groove of raphe; mounded, or flush; similar color as testa (?); reddish brown; not within corona, halo, or rim. Endosperm present; thin; not pluglike and not resembling tip of radicle; adnate to testa. Cotyledons smooth; both outer faces convex; both the same thickness; both more or less of equal length; not folded; margin not 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 S-curved; perpendicular 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

Tropical America, West Indies, Namibia.

New World and Old World; tropical United States, West Indies, Mexico, Central America, and South America; Brazil; Africa (Namibia).

Generic Notes

Britton and Rose (1930) correctly noted that the fruits were "not dehiscent along the sutures, but splitting through the middle of the valves." This character is unique in the subfamily, and perhaps in the family. They as well as Watson and Dallwitz (1983) incorrectly stated that seeds have no endosperm. Polhill and Vidal (1981) noted that there are three species, two in tropical America and the West Indies and one species in Namibia. They did not name which two New World species were recognized and which one was from Africa. Except for data and drawings in Ross (1977b), the African fruits and seeds were not studied.