Crataegus L.
Genus composed of about 380 species distributed mainly in temperate zones of the Holarctic region. In North Africa it is represented by 4 species, in the Mediterranean area. A fifth species [C. laevigata (Poir.) DC.] can be found cultivated in Algeria and Libya.
Christensen, K.I. 1992. Revision of Crataegus sect. Crataegus and nothosect. Crataeguinae (Rosaceae-Maloideae) in the old world. Systematic Botany Monographs, vol. 35. 199 págs. The American Society of Plants Taxonomists Edit.
Christensen, K.I. & Zielinski, J. 2008. Notes on the genus Crataegus (Rosaceae-Pyreae) in southern Europe, the Crimea and western Asia – Nordic J. Bot. 26: 344-360.
Key to species
1 Young branchlets, petioles, peduncles and ± also leaves covered with whitish-tomentose indumentum 2
1 Young branchlets, petioles, peduncles and leaves glabrous or sometimes villous 3
2 Leaves with 5-9 narrow and deep lobes, usually with irregularly dentate tip, tomentose-lanate. Flowers with 3-5 styles Crataegus laciniata
2 Leaves with 3-5 wide and shallow lobes, tip usually rounded or with small lobules or obtuse teeth, glabrous or slightly pubescent. Flowers with 1-2 styles Crataegus azarolus
3 Basal part of leaves and stipules with entire margin Crataegus monogyna
3 Basal part of leaves with 1-8 small teeth, stipules with dentate margin Crataegus granatensis
Updated by: A.V. Pérez Latorre.