Genista

Taxonomy

Genista C. Linnaeus Sp. Pl. 709. 1 Mai 1753.

Subfamily: Faboideae.
Phylogenetic Number: 3.30.22.
Tribe: Genisteae.
Species Studied - Species in Genus: 33 studied; 87 in genus.

Description

Fruit: A legume; unilocular; 0.8–3 cm long; 0.35–0.4 cm wide; 0.15–0.3 cm thick; 2–9 times longer than wide; with deciduous androecial sheath, or persistent androecial sheath; with deciduous corolla; with persistent calyx; with calyx shorter than fruit; without orifice formed by curving of fruit or fruit segments; straight, or curved (or slightly curved); not plicate; not twisted; asymmetrical, or symmetrical; oblong, or linear, or ovate, or rhombic, or falcate; with both sutures parallelly curved; not inflated, or inflated; compressed, or flattened (rarely), or terete; without beak; tapered at apex, or short tapered at apex; aligned with longitudinal axis of fruit, or oblique with longitudinal axis of fruit, or right-angled with longitudinal axis of fruit; tapered at base, or short tapered at base; aligned with longitudinal axis of fruit, or oblique with longitudinal axis of fruit, or right angled with longitudinal axis of fruit; with the apex and base uniform in texture; coriaceous; seed chambers externally visible, or invisible; seed chambers with the raised seed chambers not torulose, or torulose; margin not constricted; margin without sulcus; margin plain; wing(s) absent; substipitate, or nonstipitate; with all layers dehiscing, or indehiscent; splitting along suture(s). Dehiscence of valves along both sutures; apical and down; active; with valves twisting. Replum invisible. Epicarp glossy, or dull; monochrome; dark to light reddish brown; with surface texture uniform; glabrous, or pubescent and indurate; with hairs erect, or appressed; with 1 type of pubescence; tomentose, or villous; with pubescence golden, or gray; with pubescence uniformly distributed, or with apical pubescence different from basal pubescence; with apical 1/3–1/2 pubescent and basal 1/2–2/3 glabrous (G. cephalantha É. Spach); with simple hairs; pliable; with hair bases plain; eglandular; without spines; not smooth; with elevated features; veined, or not veined; obliquely veined relative to fruit length, or reticulately veined; not tuberculate; wrinkled; exfoliating in part, or 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; reddish brown; smooth and scurfy (around seeds), or hairy (rarely, minute except along sutures where much longer); without adhering pieces of testa; with hairs scattered over endocarp (minute except along sutures where much longer); subseptate, or nonseptate; with septa thin (tissue paper-like), flexible; with septa eglandular; chartaceous; not exfoliating; remaining fused to mesocarp and epicarp; without wings; entire. Seed(s) 1–7; length transverse to fruit length, or oblique to fruit length, or parallel with fruit length; neither overlapping nor touching; in 1 series. Funiculus 0.1–1.5 mm long; of 1 length only; filiform, or thick, or triangular; straight, or curved, or S-curved, or hooked. Aril present; dry, or fleshy; when fleshy topknotlike, or cupshaped; entire; covering less than 1/2 of seed; when dry rim-aril, or tongue-aril; entire; reddish brown, or tan, or white, or red (nearly).

Seed: 1.8–4.2 mm long; 1.5–3 mm wide; 1–2 mm thick; not overgrown; not angular, or angular; asymmetrical; oblong, or ovate, or reniform, or circular (more or less), or D-shaped, or irregular (somewhat), or quadrangular, or rhombic, or triangular; compressed, or terete; with surface smooth; with visible radicle and cotyledon lobes, or without visible radicle and cotyledon lobes; without external groove between radicle and cotyledon lobes, or with external groove between radicle and cotyledon lobes; with external groove between radicle and cotyledon lobes same color as testa; 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, or mottled and streaked (sometimes both faint); with frequent mottles; with frequent streaks; brown to yellowish, greenish or reddish brown, or yellow (to brownish to greenish yellow), or green, or olive, or black; with brown overlay, or black overlay; glabrous; smooth; coriaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe not visible. Hilum present; visible, or fully concealed (occasionally); concealed by funiculus, or funicular remnant; with faboid split; with the lips of the faboid split the same color as the rest of the hilum; punctiform, or larger than punctiform; 0.3 mm long; with curved outline; circular; apical at apex of radicle tip, or subapical to radicle tip; recessed; within rim; rim color of testa. Lens discernible, or not discernible; 0.5 mm long; with margins straight, or curved; oblong; elliptic, or oblong; not in groove of raphe; adjacent to hilum, or confluent with hilum; 0.1–0.2 mm from hilum; mounded, or flush; similar color as testa; not within corona, halo, or rim. Endosperm present; thick, or thin; not pluglike and not resembling tip of radicle; covering entire embryo; adnate to embryo, or 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; split over radicle; with lobes; with the interface division terminating at base of radicle; without margins recessed; tan, or yellow, or white; 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; linear, or bulbose; lobe tip straight; deflexed and parallel to cotyledon length; centered between cotyledons; 1/2 to nearly length of cotyledons, or equaling length of cotyledons, or exceeding length of cotyledons. Plumule rudimentary; glabrous.

Distribution

Europe, Canary Islands, northern Africa, and western Asia.

Old World; Europe to Mediterranean to Russia to Africa to Southwest Asia to China to Macaronesia (western, Africa (north and Canary Islands)).

Generic Notes

Gibbs (1966) revised the genus, and Gibbs and Dingwall (1971) revised its segregate Teline F.K. Medikus, now recombined with Genista.

Tribal Notes

Tribe Genisteae

Traditionally this tribe has been called Genisteae. Reveal (1997) reported that the name Cytiseae was published before the name Genisteae. Following the International Code of Botanical Nomenclature (Greuter et al., 1994), the oldest name for a taxon must be used, so Reveal suggested that this tribe should be called Cytiseae. In 1999 Reveal (1999) reversed himself, so that this tribe remains the Genisteae. Bisby (1981) summarized tribe Genisteae, following the excellent study by Polhill (1976). Bisby correctly noted that "many species have been moved from one genus to another several times and the Cytisus-Genista complex has gained a reputation as a critical group." He continued with an indepth analysis of the tribe. Polhill (1994a, 1994b) and Van Wyk and Schutte (1995a), using chemical and morphological characters, transferred five genera from Crotalarieae (27) to Genisteae: Anarthrophyllum (30.06), Argyrolobium (30.03), Dichilus (30.02), Melolobium, and Sellocharis (30.07). Cristofolini (1997) carried out a cladistic study of the tribe's biogeography, and discussed its early evolutionary history. López et al. (2000) studied the species of this tribe occurring in southwestern Spain and presented detailed descriptions for and a key to them.