Hylodendron

Taxonomy

Hylodendron P.H.W. Taubert In Engler et Prantl, Nat. Pflanzenfam. 3(3): 386. 22 Mai 1894.

Subfamily: Caesalpinioideae.
Phylogenetic Number: 1.4.41.
Tribe: Detarieae.
Group: Detarium.
Species Studied - Species in Genus: 1 studied; 1 in genus.

Description

Fruit: A legume; unilocular; 6–12 cm long; 2–3.5 cm wide; 0.5–7 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, or asymmetrical; falcate; with both sutures unequally curved, or both sutures parallelly curved, or 1 straight and 1 curved suture; widest near apex; not inflated; flattened; without beak; long 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 visible; margin not constricted; margin without sulcus; margin embellished; margin with wing(s); wing(s) present; wing(s) 6–12 mm wide; wing(s) samaroid; wing(s) basal (seed apical); substipitate; indehiscent. Replum invisible. Epicarp dull; monochrome; brown; with surface texture uniform; glabrous; eglandular; without spines; not smooth; with elevated features, or recessed features; veined; transversely veined relative to fruit length; not tuberculate; glandularly punctate; 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; with fibers; without reniform canals; solid (fibers embedded in solid layer); coriaceous. Endocarp present; visible; dull; opaque; monochrome; reddish brown; without adhering pieces of testa; nonseptate; not exfoliating; remaining fused to mesocarp and epicarp; entire. Seed(s) 1–3 (4); length transverse to fruit length; touching; in 1 series. Funiculus 0.1–6 mm long; of 1 length only; flattened; curved. Aril absent.

Seed: 10–12 mm long; 7–10 mm wide; 4–5 mm thick; not overgrown; not angular; symmetrical, or asymmetrical; circular, or D-shaped; 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; reddish brown; glabrous; not smooth; with recessed features; striate (from center outwards); osseous. Pleurogram absent. Pseudopleurogram absent. Fracture lines present; fracture line patter not indicated. Rim absent. Wing(s) absent. Raphe not visible. Hilum present; fully concealed; concealed by funicular remnant; without faboid split; punctiform; apical at apex of radicle tip, or marginal according to radicle tip (depending on seed length); flush (in notch); 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; completely concealing radicle; notched at radicle and split over radicle; 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, or perpendicular to length of seed (occasionally); without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; centered between cotyledons. Plumule rudimentary; glabrous.

Distribution

Gulf of Guinea.

Old World; Africa (Gulf of Guinea).

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.