Described as Strix nana (King 1827), with type locality of "Port Famine (Puerto Hambre)", Straits of Magellan, southern Chile.
This taxon variously has been classified as a subspecies of Glaucidium brasilianum (Ferruginous Pygmy-Owl; e.g., Peters 1940, Olrog 1963, Johnson 1967, Markham 1971, Texera 1973, Clark et al. 1978) or as an allospecies, together with Glaucidium jardinii (Andean Pygmy-Owl, which inhabits humid montane forests in the high Andes), and G. brasilianum proper (Short 1975, Vuilleumier 1985). However recent studies, including molecular studies based on cytochrome b DNA sequence data, indicate that nana is a valid species (König 1991, Heidrich et al. 1995, Wink et al. 2008).