The Red-Crested Tree Rat (Santamar-tamys rufodorsalis), one of the most unknown mammals of Columbia, was scientifically described in 1899. It has not been seen again since this time. The zoologicAl society for the conservAtion of species And populAtions (ZGAP) has fi- nanced investigations to find this species since 2006 but without any success. It has been rediscovered in quite a funny way: One individual of this species walked into the eco-lodge of the El Dorado Nature Reserve in the Sierra Madre de Santa Marta.