Calicotome spinosa (L.) Link
Spartium spinosum L., C. fontanesii Rothm.
Eng.: Thorny broom. Spa.: Jerguén, erguén, cambrón, cambrona, retama espinosa. Fre.: Calicotome épineux. Ara.: Gendul, dar chichaan. Tam.: Uzzu, azezu, agendal.
Shrub up to 2 m in height, spiny, hermaphrodite, deciduous, highly branched —sometimes intricate—, with extended branches. Stems and old branches with greyish bark, slightly or not at all fissured, glabrous. Young branchlets with 10-12 longitudinal ribs with an inverted V-shape, sericeous, greyish, sharp —as well as the old branches— like large spines. Leaves alternate, trifoliolate, without stipules, petiolate, with petiole 4-19 mm and leaflets 5-14 × 2-6 mm, obovate, obtuse, sometimes mucronate or slightly emarginate at the apex, attenuated at the base and briefly petiolulate, entire, with the upper side ± dark green, glabrous, and sericeous on the underside. Flowers solitary or in axillary fascicles of 3-8, or in racemiform inflorescences, terminal, with a sharp main axis, like a spine, pedicellate, pedicel with 3 bracteoles fused into an entire to tripartite structure. Calyx 2-3 mm, subcylindrical, greenish-yellow, sparsely sericeous, bilabiate, upper lip with 2 teeth and the lower lip with 3, very small, transversely circumcise in anthesis. Corolla 10-17 mm, papilionoid, yellow, with an obovate standard, glabrous, and wings and keel as long as the standard or somewhat longer, the keel subacute, slightly falcate. Androecium monadelphous, with 10 stamens. Ovary glabrous, and capitate stigma. Pod 20-52 × 5.8 mm, oblong or oblong-linear, straight or slightly curved, compressed, with 2 wings 1-3 mm wide at the ventral suture, green at first and blackish when mature, glabrous, with 2-9 seeds. Seeds 2.5-3.6 mm, ovoid, somewhat compressed, smooth, yellowish-brown.
Flowering:
February to May.
Fruiting:
May to July.
Habitat:
Thermophilic thickets, on calcareous substrates, from sea level up to 1,200 m in altitude.
Distribution:
Southern France, NW Italy, Corsica, Sardinia, Balearic Islands, eastern and southern Spain and North Africa (northern Algeria and northern Libya). The African plants were segregated into C. fontanesii Rothm., but the differences with C. spinosa, especially in the morphology and size of the bracteoles, are characters of little taxonomic value (this has been extensively debated).
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.