Abstract
The Wallacean shortfall is one of the most important problems regarding our knowledge of where and how to protect biodiversity. Citizen science programs can help fill this shortfall. A new record of the rare thick-head fly Myopa metallica Camras, 1992 is reported by a citizen science program from the Atacama desert after 46 years without new data and represents the second worldwide individual recorded of the species. We discuss the key role of the citizen science in the collection of new data on occurrence for rare and poorly known species.