Ciccaba vs. Strix
Some authorities (Sibley & Monroe, 1996; IOC 1.6, 2008) retain Mottled Owl (virgata), Black-and-white Owl (nigrolineata), Black-banded Owl (huhula), and Rufous-banded Owl (albitarsus) in the genus Strix. König et al. state that the general morphology and phylogenetic evidence of these four species does not indicate separation from the rest of Strix, and Restall goes on to explain that they were originally separated into the genus Ciccaba based on anatomy of the external ear. Clements (2007) and Howard & Moore (2003) recognize these species in Ciccaba, and the Opus follows in this consensus.