The desert fog oasis ecosystem of Peru and Chile comprises numerous oases along 3000 km of the Pacific coastal belt, it hosts a highly endemic flora, providing vital ecosystem services and genetic resources. However, due to their marked seasonality and fog cover they are poorly mapped, greatly compromising their conservation. Here we redress this using 479 images from the MODIS (MOD13Q1 V6 product) data/algorithm for the period 2000–2020, permitting the mapping of ephemeral vegetation, herbaceous and woody fog oases vegetation. In addition, we examine the main drivers of productivity in this unique ecosystem using generalised linear models, assess human pressures, conservation efforts, and summarise present plant diversity knowledge. The resultant map (https://gistin.users.earthengine.app/view/fogoasis) extends existing mapped areas by more than four-fold to over 17,000 km2 , revealing...