Seasonal fog allows for the development of rich fog-zone vegetation termed, lomas formations.
These unusual plant communities have been the focus of an ongoing research project by Field Museum botanist, Michael Dillon. The floristic communities of the lomas formations essentially function as terrestrial islands separated by hyperarid habitat where virtually no plants exist. No fewer than 80 localities have been recognized as unique assemblages. A map of localities and a listing of individual lomas formations are provided. The plants within the lomas formations have diverse origins including amphitropic disjuncts, semi-arid Ecuadorian and central Chilean species, montane Andean disjuncts, and many lomas endemics.