Map of the Centinela Region and documented localities of Gasteranthus extinctus. Numbers indicate the approximate locations of all populations confirmed to date, including the original collection locality (1) and the four sites where we observed the species in 2021 (2–5). Site 6 is from iNaturalist occurrence records. The hollow circle indicates a site where we searched for, but did not find G. extinctus. See Appendix 1 for a detailed description of each site. Inset: the placement of the Centinela Region in the Santo Domingo de los Tsáchilas Province (grey lines) in western Ecuador.