Opuntia Miller

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 : 299

1. Opuntia Miller 3

Somewhat woody; stems with short, cylindrical or flattened, often tuberculate joints. Leaves small, subulate, caducous. Areoles bearing many glochids and usually longer, stouter spines. Ovary spiny or spineless. Seeds hard, pale, more or less discoid or angular.

1 Joints readily detachable 1. tuna 1 Joints not readily detachable, persistent

2 Plants less than 1 m, shrub-like, procumbent or ascending

3 Areoles brown-lanate; spines brownish-white; fruit with flat umbilicus 2. vulgaris 3 Areoles not lanate; spines yellow; fruit with depressed umbilicus 4. stricta 2 Plantsmorethan1 m, usuallytree-like,oftenwithtrunk

4 Spines absent or rarely 1-2, less than 1 cm; glochids yellow; fruit with depressed umbilicus 5. flcus-indica 4 Spines 1-4, more than 1 cm; glochids brownish; fruit with flat umbilicus

5

Joints bright, shining green; areoles lanate; spines 1 -2, yellow to dark reddish; fruit reddish-purple 3. monacantha

5

Joints dull green, slightly glaucous; areoles not lanate; spines 1 -4, white; fruit yellowish-red 6. maxima