Ridgely, R. S., T. F. Allnutt, T. Brooks, D. K. McNicol, D. W. Mehlman, B. E. Young, and J. R. Zook. 2005. Digital Distribution Maps of the Birds of the Western Hemisphere, version 2.1. NatureServe, Arlington, Virginia, USA. Additional updates and changes by BirdPhotos.com 2016.
Believed to be extinct until it was rediscovered in 2019 near San Pedro de Los Milagros, its historical location. Similar to [Slaty Brushfinch] but less grey and more white, and without a black mark under the malar stripe. Vocally more similar to a [Yellow-breasted Brushfinch], also present in its range. After its rediscovery, it was found at other locations north of Santa Rosa in the same 'altiplano'.