6, see text Alluaudia is a genus of flowering plants in the family Didiereaceae.

[1] Most occur in the southwestern subarid forest-thicket vegetation of the island.

[2] Species of Alluaudia are dioecious, with male and female flowers on separate plants.

[3] Spines are arranged around the leaves as a defense against herbivores.

The spines are several meters above the ground, and probably evolved in response to herbivory by now-extinct lemurs, such as Hadropithecus.