''Alluaudia procera'', or Madagascar ocotillo, is a deciduous

succulent plant In botany, succulent plants, also known as succulents, are plants with parts that are thickened, fleshy, and engorged, usually to retain water in arid climates or soil conditions. The word ''succulent'' comes from the Latin word ''sucus'', meani ...

species of the family Didiereaceae. It is endemic to south Madagascar.Kew World Checklist of Selected Plant Families
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Description

This plant is a spiny succulent shrub, with thick water-storing stems and leaves that are deciduous in the long dry season. Although strikingly similar in appearance, it is not closely related to the ocotillo, '' Fouquieria splendens'' of the Sonoran Deserts in North America. Young alluaudias form a tangle of stems that last for several years, after which a strong central stem develops. The basal stems then die out, leaving a tree-like stem that branches higher up on the main trunk. Like other members of family Didiereaceae, the leaves of ''Alluaudia'', produced from brachyblasts similar to the areoles found in cacti, are small, appear single and are accompanied with conical spines. Its flowers are unisexual and radially symmetric. Alluaudia procera leaves

Taxonomy

The Didiereaceae comprise 11 species divided into 4 genera, of which the largest is '' Alluaudia'' (six species). Alluaudia has been subdivided into the 2 sections ''Alluaudia'' and ''Androyella''. In this way, ''Alluaudia procera'' has two sisters, ''

Alluaudia ascendens ''Alluaudia ascendens'' is a species of ''Alluaudia'' endemic to Madagascar.''Alluaudia''.
Madag ...

'' and ''

Alluaudia montagnacii ''Alluaudia montagnacii'' is a rare species of flowering plants belonging to the family Didiereaceae. Description ''Alluaudia montagnacii'' can reach a height of . The tall columnar central trunk sprouts strong vertical branches. Stem and bran ...

''. Based on molecular phylogeny conducted '' Alluaudia'', ''Alluaudiopsis'', and ''Didierea'' from the family are all supported as monophyletic. Relationships within the genus ''Alluaudia'' are relevant to the evolution of polyploidy within the family. Researchers haven't figured out where the family Didiereaceae originates. However, the nearest relative of the Didiereaceae, ''Calyptrotheca somalensis'', is endemic to East Africa, from which the island of Madagascar separated 100 million years ago. Thus, the Didiereaceae may have originated from the dispersal to Madagascar of a ''Calyptrotheca''-like East African ancestor.

References

{{Taxonbar, from=Q287086 Didiereaceae Endemic flora of Madagascar Near threatened plants Plants described in 1903 Flora of the Madagascar spiny thickets