The Spectacled Owl (Pulsatrix perspicillata) seems to be uncommon near the southern limit of the species' range. Here, we report new records for the Spectacled Owl, identify the subspecies, and examine the spatial distribution of records in the southern part of the species' range. We made 50 sightings of at least two adults and six juveniles over 3 yr in a gallery-forest habitat within Estancia Guaycolec, Formosa, Argentina (25°58′S, 58°10′W). We compared the external morphology of the adults found in Estancia Guaycolec with those of the P. p. boliviana, P. p. pulsatrix, and P. p. perspicillata subspecies, and found great similarity with the features of P. p. perspicillata. We also analyzed the vocalizations of an adult recorded at Estancia Guaycolec and found that its calls accelerated towards the end, as has been reported for P. p. perspicillata. Spatial analysis of records from the southern region of the Spectacled Owl's range showed an alignment of the records from the Chaco region alongside the Paraguay River. The gallery forests along the banks of the Paraguay River and its tributaries seem to provide P. p. perspicillata with a continuum of suitable habitats, extending its range southward. Conservation of this riparian corridor is likely crucial to maintain the current distribution of the species.