Rhamnus L.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1981, Flora Europaea. Volume 2. Rosaceae to Umbelliferae, Cambridge University Press : 244

3. Rhamnus L. 1

Germination epigeal. Winter buds with scales. Stipules subulate, caducous. Flowers 4-merous or sometimes 5-merous, usually unisexual but monoecious. Styles 3—4; stigmas small. Fruit a drupe with 2-4 pyrenes. Literature: S. Rivas Martinez, Anal. R. Acad. Farm. (Madrid) 28: 363-397 (1962). W. Vent, Feddes Reperì. 65: 3-132 (1962) (Sect. Rhamnastrum). 1 Leaves evergreen

2 Spines present; flowers usually 4-merous, in cymose fascicles or rarely solitary 3. lycioides

2 Spines 0; flowers 5-merous, in racemes, or rarely solitary

3 Leaves entire or remotely denticulate 1. alaternus

3 Leaves strongly and closely spinose-denticulate 2. ludovici-salvatoris

1 Leaves deciduous

4 Leaves all alternate; spines 0

5 Leaves tomentose on both surfaces 13. sibthorpianus

5 Leaves glabrous or somewhat hairy but not tomentose on both surfaces

6 Usually erect, 100-400 cm; leaves with (5-)7-20 pairs of lateral veins 11. alpinus

6 Procumbent, 5-20 cm; leaves with 4—9(—13) pairs of lateral veins 12. pumilus

4 Lower leaves mostly opposite or subopposite; lateral twigs usually spinescent

7 Lamina of leaves on short shoots 1-2| times as long as petiole; petiole 2-3 times as long as stipules

8 Lamina of leaves on short shoots 2 -2 | times as long as petiole, ovate to elliptical 8. catharticus

8 Lamina of leaves on short shoots about as long as petiole, usually orbicular 9. orbiculatus

7 Lamina of leaves on short shoots 3-6 times as long as petiole; petiole not or scarcely longer than stipules

9 Leaves mostly less than 1 cm; lateral veins inconspicuous

10 Leaves oblong or ovate 7. prunifolius

10 Leaves obovate 3. lycioides

9 Leaves 1-6 cm; lateral veins conspicuous

11 Mature leaves pubescent beneath

12 Leaves 3 |-4 | times as long as wide, glabrous above

10. persicifolius

12 Leaves rarely more than 3 times as long as wide, pubescent above 5. rhodopeus

11 Mature leaves glabrous or with hairs on veins and petiole only

13 Leaves ± orbicular 6. intermedius

13 Leaves lanceolate, ovate or obovate

14 Leaves crenate-serrate 4. saxatilis

14 Leaves entire 3. lycioides