Rafnia

Taxonomy

Rafnia C.P. Thunberg Nova Gen. Pl. 144. 3 Jun 1800; 123. 1800. 3 Jun 1800.

Subfamily: Faboideae.
Phylogenetic Number: 3.27.05.
Tribe: Crotalarieae.
Species Studied - Species in Genus: 8 studied; 19 in genus.

Description

Fruit: A legumelegume:
usually dry, dehiscent fruit derived from a single carpel that opens along two longitudinal sutures
; unilocular; 0.9–5.3 cm long; 0.3–1.8 cm wide; 0.2–0.3 cm thick; 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; straight; not plicate; not twisted; asymmetrical; lanceolate (linear), or oblanceolate, or linear, or oblong (narrowly to broadly); with 1 straight and 1 curved suture, or both sutures parallelly curved; widest at base, or widest near apex; not inflated; compressed; without beak; short tapered at apex; aligned with longitudinal axis of fruit; tapered at base; aligned 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 to plain; margin with wing(s); wing(s) present, or absent; wing(s) 1; wing(s) 1–5 mm wide; wing(s) sutural (along upper suture and usually best developed near calyx); wing(s) on 1 suture; stipitate, or substipitate, or nonstipitate; with the stipe 0.1–16 mm long; with all layers dehiscing; splitting along suture(s). Dehiscence of valves along both sutures; apical and down; active; with valves enrolling, or twisting. Replum invisible. Epicarp dull; monochrome; black, or brown (dirty); with surface texture uniform; glabrous; eglandular; without spines; not smooth; with elevated features; veined; reticulately veined; not tuberculate; lenticular (tannish); 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; nearly spongy, or solid; coriaceous. Endocarp present; visible; dull, or glossy; opaque; monochrome; brown (to reddish); reticulate, or hairy (appressed and silver); without adhering pieces of testa; nonseptate; chartaceous; not exfoliating; remaining fused to mesocarp and epicarp; with wing(s) extending into epicarp, or without wings; entire. Seed(s) 1–5; length assumed parallel with fruit length. Funiculus thick; straight. Aril absent.

Seed: 2–6 mm long; 1–5 mm wide; 0.8–2 mm thick; not overgrown; not angular; asymmetrical; reniform to oblong (narrowly to broadly), or circular; compressed; with visible radicle and cotyledon lobes; without external groove between radicle and cotyledon lobes; 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 mottled and streaked; with frequent mottles; with frequent streaks; reddish brown, or tan, or black, or white (grayish), or yellow (pale); with black overlay (grayish); glabrous; smooth, or not smooth; with elevated features, or recessed features (rarely); wrinkled, or tuberculate; longitudinally striate (Rafnia vlokii G.J. Campbell & B.-E. van Wyk); coriaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe not visible. Hilum present; visible; with faboid split; with the lips of the faboid split the same color as the rest of the hilum; larger than punctiform; 0.5–0.7 mm long; with straight outline, or curved outline; elliptic; oblong; between cotyledon and radicle lobe; recessed; within rim; rim color darker than testa (slightly to black), or lighter than testa. Lens discernible; 0.5–1 mm long; with margins straight, or curved; narrowly oblong; narrowly oblong; not in groove of raphe; adjacent to hilum; mounded; dissimilar color from testa; darker than testa; black, or brown (dark to reddish to greenish); not within corona, halo, or rim. Endosperm present; thin; not pluglike and not resembling tip of radicle; covering entire embryo; adnate to testa. 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; not concealing radicle; entire over radicle; without lobes; with the interface division terminating at base of radicle; without margins recessed; brownish red; inner face flat; glabrous on inner face. Embryonic axis deflexed; oblique to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; bulbose; deflexed and parallel to cotyledon width; centered between cotyledons; less than 1/2 length of cotyledons. Plumule rudimentary; glabrous.

Distribution

South Africa (Southwestern Cape Province to Natal).

Old World; Africa (endemic to South Africa).

Generic Notes

Campbell and van Wyk (2001) revised Rafnia, and their species number and distribution were used.

Tribal Notes

Tribe Crotalarieae

Polhill (1981q) broadly defined tribe Crotalarieae with two generic groups. The first group, without a two-lipped calyx, formed a tight cluster around Lebeckia (3.27.10) in southern Africa. The second group, with a two-lipped calyx, had more scattered distributions and uncertain affinities. Van Wyk (1991) followed Polhill (1981q), and transferred Argyrolobium (3.30.03) from Genisteae (3.30) to the second group. Crotalarieae and related tribes are rich in alkaloids which have been extensively studied in the last decade (Hussain et al. 1988; Van Wyk and Verdoorn, 1989a, 1989b, 1989c, 1990, 1991a, 1991b; Van Wyk et al., 1989, 1993; Verdoorn and Van Wyk, 1990, 1991). Polhill (1994a, 1994b) and Van Wyk and Schutte (1995a), using chemical and morphological data, restricted Crotalarieae to the genera without a two-lipped calyx, and transferred those with a two-lipped calyx to Genisteae, Anarthrophyllum (3.30.06), Argyrolobium (3.30.03), Dichilus (3.30.02), Melolobium (3.30.01), and Sellocharis (3.30.07), except Lebeckia. They also more or less inverted the generic order within the first group according to Van Wyk and Schutte's cladistic analysis for the genera of Crotalarieae, in the narrow sense.