This ecoregion occurs in northwestern India, along the Aravalli Mountains (formed over 1,500 million years ago). The stunted, xerophytic (adapted to dryness) vegetation, dominated by species of Acacia (< 6 m in height), includes trees and shrubs such as Prosopis cineraria, Grewia, Salvadora, Zizyphus, Anogeissus, Gardenia, Capparis, and Carissa. Climbers such as Tragia, Rivea, Tinospora, Vitis, and Peristrophe also occur. The thorn forests transition in drier areas into cactus-like Euphorbia scrub. Near the coast where soils are more saline Salvadora and Tamarix occur, while areas with very high salinity lack vegetation. Climatically, the region is dry, with an average annual rainfall of about 750 mm in the northern areas and about 950 mm further south.