Cytisus fontanesii Spach
Spartium biflorum Desf., Genista biflora (Desf.) DC, Chronanthus biflorus (Desf.) Frodin & Heywood
Spa.: Bolina, ginestrilla. Ara.: Erka.
Subshrub, up to 0.5(0.8) m in height, unarmed, deciduous, hermaphrodite, with upright stems and hemispherical in shape. Stems and old branches brownish bark, fissured longitudinally. Young branchlets with 5 triangular ribs, acute, green, from glabrescent to hairy. Leaves all trifoliolate, with stipules poorly differentiated. Petiole up to 3mm. Leaflets 3-10 × 1.2-1.7 mm, from elliptic to oblanceolate, with ± involute margins, ± adpressed-hairy on both sides. Flowers solitary or more frequently arranged in dense groups in of 2-12, on a pedicel of 2-5 mm, with a foliaceous bracteole halfway. Calyx 3-8 mm, campanulate, membranous, green at first then brown-blackish, ± hairy, bilabiate, with slightly dentate lips: the upper lip with 2 teeth and the lower lip with 3. Corolla 11-20 mm, papilionoid, yellow, glabrous; with elliptic standard, emarginate, the same length or slightly longer than the wings and keel; the keel with the tip slightly curved upwards. Androecium monadelphous, with 10 stamens. Ovary and syle glabrous, the style curved upwards. Pod 10-16 × 5.5-8 mm, obovate-rhomboid, compressed, semi-enclosed by the calyx and marcescent corolla; at first green, then blackish, ± hairy. Seeds 1-2, ovoid, compressed, smooth, from brownish to black.
Flowering:
February to July.
Fruiting:
April to August.
Habitat:
Fairly open forests and sparse thickets on limestone, chalky and loamy soils; in dry to semiarid environments. With a relatively large altitudinal range, from near sea level to 1,400 m.
Distribution:
Iberian Peninsula, Ibiza and NW Africa.
Observations:
Several subspecies have been recognised. C. fontanesii Spach subsp. fontanesii [incl. C. fontanesii var. incanus Maire, C. fontanesii subsp. incanus (Maire) Tahiri ex Fennane & Ibn Tattou] includes glabrous or glabrescent plants, and if they have hairs they are less than 1 mm and usually applied. It is distributed across eastern and southern Spain, in the Balearic Islands (Ibiza) and in NW Africa. In the latter in central and northern Morocco, and northern Algeria (Tellian Atlas, and NO areas of the high steppic plateaux). In contrast, C. fontanesii subsp. plumosus (Boiss.) Nyman (Genista biflora var. plumosa Boiss.), groups plants with velutinous calyx and leaves, with hairs 1.2-2.5 mm, straight, patent. This subspecies, described from plants in southern Spain, seems also to extend its distribution into NW Morocco (W of the Rif, and Middle Atlas).
Conservation status:
A relatively common and widely distributed species, not considered threatened. Currently, it has not been assessed at a global level in the IUCN Red List of Threatened Species.