The Coastal cordillera rises steeply from a narrow plain seldom exceeding a few kilometres in width. It is characterised by a distinct geology and a type of erosion known as tafoni which is a form of salt weathering resulting in a pitted or honeycomb rock formation. Exceeding 1000 m or more in altitude, mountains of the cordillera are often sharply dissected by steep sided valleys; with a rise in altitude, the vegetation becomes more abundant and is often associated with river systems which support small trees and shrubs. Mountain slopes are notable habitats for a wide range of cactus species, mostly belonging to the endemic genus Copiapoa. At higher altitudes rainfall is more abundant and being far from the sea and away from the influence of the Humboldt current, the temperatures are somewhat warmer. Mountain peaks can rise steeply within relatively short distances, as is the case in Pan de Azúcar National Park, an area known for its remarkable plant diversity, the majority of which is endemic.
Endemic Taxa in Coastal cordillera (semidesert)
- Adesmia araucana Phil.
- Adesmia argentea Meyen
- Adesmia argyrophylla Phil.
- Adesmia aromatica Burkart
- Alstroemeria kingii Phil.
- Alstroemeria polyphylla Phil.
- Alstroemeria schizanthoides Grau var. schizanthoides
- Alstroemeria zoellneri Ehr. Bayer
- Buddleja suaveolens Kunth & Bouché
- Cistanthe oblongifolia (Barnéoud) Carolin ex Hershk.
- Cistanthe vicina (Phil.) Carolin ex Hershk.
- Colliguaja odorifera Molina
- Conanthera campanulata Lindl.
- Fabiana viscosa Hook. & Arn.
- Helenium glaucum (Cav.) Stuntz
- Kageneckia angustifolia D. Don
- Malesherbia fasciculata D. Don var. fasciculata
- Malesherbia humilis var. parviflora (Phil.) Ricardi
- Malesherbia linearifolia (Cav.) Pers.
- Malesherbia paniculata D. Don
- Nolana divaricata (Lindl.) I.M. Johnst.
- Nolana parviflora (Phil.) Phil.
- Nolana pterocarpa Phil. ex Wettst.
- Nolana sedifolia Poepp.
- Nolana werdermannii I.M.Johnst.
- Solanum brachyantherum Phil.
- Tristerix aphyllus (Miers ex DC.) Barlow & Wiens