Cytisus Desf.

Key to species

1 Shrub with sharp branches, spiny, usually cushion-shaped 2

1 Shrub unarmed 4

2 Corolla white Cytisus albidus

2 Corolla yellow 3

3 Leaves trifoliolate Cytisus pulvinatus

3 Leaves unifoliolate Cytisus balansae

4 Style slightly longer than the ovary, not inrolled 5

4 Style much longer than the ovary, inrolled and sometimes ±dilated at the apex at anthesis 6

5 Leaflets larger than the leaves, 5-20 mm wide, obovate or oblong-obovate; stems slightly angular, with 5 semicylindrical and distant ribs, with double indumentum, with hairs 0.5-1.5 mm, straight and patent, and crisped or uncinate hairs smaller in size; h Cytisus villosus

5 Leaflets larger than the leaves, 1.2-2 mm wide, narrowly ellipticalor oblanceolate; stems polygonal in cross section, with 5 ribs in an inverted V-shape,without short hairs, uncinate or crisped in the intercostal valleys; glabrous ovary; Pod 10-16 mm Cytisus fontanesii

6 Young stems polygonal in cross section, with 5-7 acute ribs in an inverted V-shape, without short hairs, uncinate or crisped in the intercostal valleys 7

6 Stems rounded, with (5)7-8(9) T-shaped ribs, with numerous short hairs, uncinate or crisped in the intercostal valleys 8

7 Ovary and pod densely villous Cytisus grandiflorus

7 Ovary and pod ciliate only on the margins Cytisus scoparius

8 Lower leaves trifoliolate, upper leaves unifoliolate; acute and falcate keel; style widened at the top; pod densely villous Cytisus striatus

8 Leaves all trifoliolate; keel obtuse; style ± cylindrical throughout its length; pod villous, glabrous or glabrescent Cytisus arboreus