Endemic to southwest Peru, the Cactus Canastero is also confined to the Peru-Chile Pacific Slope Endemic Bird Area. It is a poorly known and little-studied species that is usually encountered alone or in pairs. There is some disagreement in the literature as to the species’ taxonomy, with some authorities recognizing the race Pseudasthenes cactorum monticola for the higher Andean populations, and another subspecies, P. c. lachayensis, which has a highly restricted range in the Lomas de Lachay, near Lima. However, many works do not treat either of these subspecies as anything more than individual variation. Although the Cactus Canastero is known to nest in cacti, almost nothing further has been published concerning the species’ breeding behavior, although the young are fed insects and caterpillars, and adults have also been seen consuming cactus fruits.