The Madagascar spiny forests (also known as the Madagascar spiny thickets) is an

ecoregion An ecoregion (ecological region) is an ecological and geographic area that exists on multiple different levels, defined by type, quality, and quantity of environmental resources. Ecoregions cover relatively large areas of land or water, and c ...

in the southwest of

Madagascar Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, f ...

. The

vegetation type Vegetation classification is the process of classifying and mapping the vegetation over an area of the Earth's surface. Vegetation classification is often performed by state based agencies as part of land use, resource and environmental management ...

is found on poor substrates with low, erratic winter rainfall. The ecoregion contains an outstanding proportion of endemic plant species and is listed as one of the 200 most important ecological regions in the world; one of the

Global 200 The Global 200 is the list of ecoregions identified by the World Wide Fund for Nature ( WWF), the global conservation organization, as priorities for conservation. According to WWF, an ecoregion is defined as a "relatively large unit of land or w ...

Flora

This is the area with the highest level of plant endemism in Madagascar, with 48% of the genera and 95% of the species endemic.Elmqvist T, Pyyko ̈nen M, Tengo ̈M, Rakotondrasoa F, Rabakonandrianina E, et al (2007) Patterns of Loss and Regeneration of Tropical DryForest in Madagascar: The Social Institutional Context. PLoS ONE 2(5): e402. doi:10.1371 Many constituent plants show extreme adaptations to drought. Spiny plants of the endemic subfamily Didiereoideae form a conspicuous component, especially towards the east. They are woody but distantly related to the

cacti A cactus (: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (), a family of the order Caryophyllales comprising about 127 genera with some 1,750 known species. The word ''cactus'' derives, through Latin, ...

. The remaining component of the forests is dominated by members of the plant families

Burseraceae The Burseraceae are a moderate-sized family of 17-19 genera and about 540 species of woody flowering plants. The actual numbers given in taxonomic sources differ according to taxonomic revision at the time of writing. The Burseraceae are also ...

Euphorbiaceae Euphorbiaceae (), the spurge family, is a large family of flowering plants. In English, they are also commonly called euphorbias, which is also the name of Euphorbia, the type genus of the family. Most spurges, such as ''Euphorbia paralias'', ar ...

Anacardiaceae The Anacardiaceae, commonly known as the cashew family or sumac family, are a family of flowering plants, including about 83 genera with about 860 known species. Members of the Anacardiaceae bear fruits that are drupes and in some cases produce ...

and

Fabaceae Fabaceae () or Leguminosae,International Code of Nomen ...

, all of which have representatives elsewhere.

Fauna

Notable inhabitants of the spiny thickets include the spider tortoise ('' Pyxis arachnoides'') and the radiated tortoise (''

Astrochelys radiata The radiated tortoise (''Astrochelys radiata'') is a tortoise species in the family Testudinidae. Although this species is native to and most abundant in southern Madagascar, it can also be found in the rest of this island, and has been introd ...

''), the gecko '' Ebenavia maintimainty'', several lemurs including

Verreaux's sifaka Verreaux's sifaka (''Propithecus verreauxi''), or the white sifaka, is a medium-sized primate in one of the lemur families, the Indriidae. Critically Endangered, it lives in Madagascar and can be found in a variety of habitats from rainforest to ...

Grandidier's mongoose Grandidier's mongoose (''Galidictis grandidieri''), also known as the giant-striped mongoose or Grandidier's vontsira, is a small carnivoran that lives only in a very small area of southwestern Madagascar, in areas of spiny forest vegetation. It ...

, and eight endemic birds.

Conservation

8.31% of the ecoregion is in protected areas. including

Tsimanampetsotsa National Park Tsimanampetsotsa National Park also spelt Tsimanampetsotse, and known as Tsimanampetsotsa Nature Reserve is a 432 km2 national park on the south-west coast of Madagascar in the region Atsimo-Andrefana. The park is south of Toliara and south ...

, Berenty Reserve, Beza Mahafaly Reserve, and Cap Sainte Marie Special Reserve.

Andohahela National Park The Andohahela National Park is situated in Anosy in the south-east of Madagascar. It is remarkable for the extremes of habitats that are represented within it. The park covers of the Anosy mountain range, the southernmost spur of the Malagasy H ...

offers limited protection through its 'parcel 3' section. Elsewhere the spiny forest habitat is under pressure from human exploitation. The main impacting activities are burning for conversion to grazing land, harvesting for charcoal and firewood, and logging for construction. The

Arboretum d'Antsokay Arboretum d'Antsokay or Antsokay Arboretum is a botanical garden near the city of Toliara in Madagascar. About 900 plant species grow in the Arboretum, 90% of these endemic to Madagascar, 80% of them considered to have medicinal value and many th ...

is a botanical garden near

Toliara Toliara (also known as ''Toliary'', ; formerly ''Tuléar'') is a city in southern Madagascar. It is the capital of the Atsimo-Andrefana region, located 936 km southwest of the national capital Antananarivo. The current spelling of the name ...

dedicated to preserving the flora of the spiny forest.

Extent

Ecoregions and forest types in Madagascar

As shown on the map on the right, Madagascar can be divided into four climatic

s with four forest types: the moist forest in the East (green), the dry forest in the West (orange), the spiny forest in the South (red), and the

mangrove forest Mangrove forests, also called mangrove swamps, mangrove thickets or mangals, are productive wetlands that occur in coastal intertidal zones. Mangrove forests grow mainly at tropical and subtropical latitudes because mangrove trees cannot withsta ...

on the West coast (blue). Ecoregions were defined following climatic and vegetation criteria.Ministère de l’Environnement (1996) "IEFN: Inventaire Ecologique Forestier National", Tech. Rep., Ministère De l’Environnement De Madagascar, Direction Des Eaux Et Forêts, DFS Deutsch Forest Service GmbH, Entreprise d’études de développement rural “Mamokatra”, FTM. The dark grey areas represent the remaining natural forest cover for the year 2014. Forest types are defined on the basis of their belonging to one of the four ecoregions.

References

External links and bibliography

* For extent, fragmentation and intact sections, see: ''A refined classification of the primary vegetation of Madagascar based on the underlying geology'', Du Puy and Moat, 1996. * For dominant plant families, see: ''Structure and floristic composition of the vegetation in the Réserve Naturelle Intégrale d’Andohahela, Madagascar'', Rakotomalaza and Messmer, 1999. *{{WWF ecoregion, name=Madagascar spiny thickets, id=at1311
Madagascar spiny thickets (Encyclopedia of the Earth)
Deserts and xeric shrublands Ecoregions of Madagascar Atsimo-Andrefana Anosy Androy

Flora

Fauna

Conservation

Extent

See also

References

External links and bibliography