Hardenbergia

Taxonomy

Hardenbergia G. Bentham In Endlicher et al., Enum. Pl. Hügel. 40. Apr 1837.

Subfamily: Faboideae.
Phylogenetic Number: 3.10.48.
Tribe: Phaseoleae.
Subtribe: Kennediinae.
Species Studied - Species in Genus: 2 studied; 2 in genus.

Description

Fruit: A legume; unilocular; 3.5–4.5 cm long (from literature); 0.3–1.1 cm wide (from literature); 0.4 cm thick (from literature); 2–9 times longer than wide; with deciduous androecial sheath; with deciduous corolla; with persistent calyx; with calyx shorter than fruit; without orifice formed by curving of fruit or fruit segments; slightly curved; not plicate; not twisted; asymmetrical; nearly linear; with both sutures parallelly curved; not inflated; compressed to terete; without beak; short tapered at apex; aligned with longitudinal axis of fruit (nearly); tapered at base to short tapered at base; oblique with longitudinal axis of fruit; with the apex and base uniform in texture; coriaceous; seed chambers externally invisible; margin not constricted; margin without sulcus; margin embellished; margin with thickened sutural areas; wing(s) absent; nonstipitate; with all layers dehiscing; splitting along suture(s). Dehiscence of valves along both sutures; apical and down; active; with valves twisting. Replum invisible. Epicarp dull; monochrome; brown (to violet brown in literature); with surface texture uniform; glabrous; eglandular; without spines; not smooth; with elevated features, or recessed features; not veined; not tuberculate; minutely, obliquely rugose; slitted obliquely; not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; thin; surface not veined; 1-layered; without balsamic vesicles; without fibers; without reniform canals; solid; coriaceous. Endocarp present; visible; dull; opaque; monochrome; orangish brown, or tan; smooth, or cracked; without adhering pieces of testa; nonseptate; chartaceous; exfoliating in part; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) 5–6; length transverse to fruit length; neither overlapping nor touching; in 1 series. Funiculus 0.5–2 mm long; of 1 length only; flattened; triangular. Aril present; fleshy; when fleshy annular to 2-lipped rim-aril (with lips fused, but thinner in area of fusion); entire to crenate; covering less than 1/2 of seed; with tongues (or flap) on lips of 2-lipped rim-aril; with 1 tongue or flap on 1 lip of 2-lipped rim-aril, or 2 tongues or flaps, 1 on each lip of 2-lipped rim-aril.

Seed: 5.5–9 mm long; 2.6–4.5 mm wide; 2.5–4 mm thick; not overgrown; not angular; asymmetrical; elliptic to rectangular; 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; brown; glabrous; smooth; chartaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe not visible. Hilum present; partially concealed; concealed by aril; with faboid split; with the lips of the faboid split the same color as the rest of the hilum; larger than punctiform; 2.5–4 mm long; with curved outline; elliptic; marginal according to radicle tip; flush; not within corona, halo, or rim. Lens discernible; 0.5–1.5 mm long; with margins straight; linear; not in groove of raphe; confluent with hilum; flush; similar color as testa; darker than testa; within halo; halo color darker than testa. Endosperm present; thick; covering entire embryo; adnate to embryo. Cotyledons not smooth; sulcate; 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; not concealing radicle; split over radicle; without lobes; with the interface division terminating at base of radicle; without margins recessed; tan; inner face flat; glabrous on inner face. Embryonic axis oblique; oblique to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; bulbose; lobe tip curved; oblique to cotyledons; centered between cotyledons; less than 1/2 length of cotyledons. Plumule well developed; glabrous.

Distribution

Australia.

Old World; Australia.

Generic Notes

Berg (1979) studied the myrmecochorous dispersal of Hardenbergia and Kennedia (10.47) seeds.

Tribal Notes

Tribe Phaseoleae

Bruneau et al. (1995) carried out cladistic analyses of tribe Phaseoleae using chloroplast DNA restriction site data. Their results indicated that the tribe is not monophyletic and that the tribal delimitations between Phaseoleae and Desmodieae (11) and between Phaseoleae and Millettieae (7) are problematic.