The Madagascar spiny thickets, also known as the Madagascar spiny forests, occupy southern and southwestern Madagascar, stretching from the Mangoky River on the west coast to the Anosyennes Mountains in the southeast. Their signature vegetation is dominated by the endemic family Didiereaceae (subfamily Didiereoideae), woody spiny plants unrelated to true cacti, alongside baobabs (Adansonia) and members of the Burseraceae and Euphorbiaceae. The climate is extremely arid, with low and erratic rainfall and prolonged droughts that can last several years, so the plants show extreme adaptations such as swollen succulent trunks, reduced or succulent leaves, and thorns. This ecoregion has the highest level of plant endemism in Madagascar, with about 95 percent of its plant species found nowhere else, and its flagship species is the radiated tortoise. For gardeners, several striking drought-adapted ornamentals are native here, including Pachypodium, Aloe, the octopus tree (Didierea), and the Madagascar ocotillo (Alluaudia procera).
Marker placed inside the RESOLVE 2017 polygon at 24.9°S, 44.6°E.
Climate snapshot for this ecoregion
°C
°F
Current zone range (2011–2040)
12a-13b
Plotwright
CHELSA-derived typical winter month at this ecoregion's bbox grid.
Projected (2041–2070)
12a-13b
Plotwright
Where the CHELSA models say the typical winter month is heading.
Average warming this ecoregion is on track for: +3.2°F by mid-century. SSP3-7.0 (current trajectory) · CHELSA v2.1 bio06 sampled across 10 of 10 points within this ecoregion's bounding box.
At a glance
Dominant biome
Deserts & Xeric Shrublands
Realm
Afrotropic
Approximate area
16,751 sq mi
Conservation tier
Nature Imperiled (Dinerstein NNH 4)
About the deserts & xeric shrublands biome
Arid and semi-arid lands where low, erratic rainfall and high evaporation limit vegetation to drought-adapted shrubs, succulents, and sparse grasses. Day-to-night temperature swings are large, and life is finely tuned to water scarcity.
Catalog plants suited to this ecoregion
Computed from each plant's stated USDA zone range against this ecoregion's CHELSA-derived current zone range, with the CHELSA mid-century warming delta applied for the projection. Plants whose stated range falls outside both the current and projected zone end up dropped; the rest land in one of the three buckets below.
Climate-resilient picks · 4
These plants fit this ecoregion today AND remain in range under the mid-century SSP3-7.0 projection. Lead with these for a planting that holds up as the climate shifts.
No curated collection's plants all fit this ecoregion's zone range. We surface a collection only when every member would grow here — partial fits get filtered out rather than mislead. As the catalog and the curated set both grow, this section will fill in.
Related ecoregions
Other deserts & xeric shrublands ecoregions to explore: