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 (albitarsis) 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. While Clements (2007) and Howard & Moore (2003) do recognize Black-and-white Owl and Black-banded Owl as being in Ciccaba, Howard & Moore deviate from Clements and retain Mottled Owl and Rufous-banded Owl in Strix alongside aforementioned authorities. The Opus awaits further clarification.