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

deciduous In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...

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 In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Didiereaceae Didiereaceae is a family of flowering plants found in continental Africa and Madagascar. It contains 20 species classified in three subfamilies and six genera. Species of the family are succulent plants, growing in sub-arid to arid habitats. Seve ...

. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to south

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

.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'' (commonly known as ocotillo (), but also referred to as buggywhip, coachwhip, candlewood, slimwood, desert coral, Jacob's staff, Jacob cactus, and vine cactus) is a plant indigenous to the Sonoran Desert and Chihuahuan ...

, ''

Fouquieria splendens ''Fouquieria splendens'' (commonly known as ocotillo (), but also referred to as buggywhip, coachwhip, candlewood, slimwood, desert coral, Jacob's staff, Jacob cactus, and vine cactus) is a plant indigenous to the Sonoran Desert and Chihuahua ...

'' of the

Sonoran Desert The Sonoran Desert ( es, Desierto de Sonora) is a desert in North America and ecoregion that covers the northwestern Mexican states of Sonora, Baja California, and Baja California Sur, as well as part of the southwestern United States (in Arizona ...

s 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 ''Alluaudia'' is a genus of flowering plants in the family Didiereaceae. There are six species, all endemic to Madagascar. Most occur in the southwestern subarid forest-thicket vegetation of the island. Species of ''Alluaudia'' are dioecious, ...

'' (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 ''

'', ''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