Sulawesi Scops-owl (Otus manadensis) - HBW 5, p. 167

Taxonomy: Scops manadensis Quoy and Gaimard, 1830, Manado, Sulawesi.
Probably forms superspecies with O. elegans and O. collari. Formerly treated as conspecific with O. magicus; also sometimes as including O. beccarii as race. Recently listed as including O. elegans as race, perhaps in error. Has traditionally been considered to include birds from Sangihe I, recently described as O. collari. Sulu form sibutuensis, included with O. mantananensis, sometimes placed with present species. Classification and true affinities of Otus taxa in SE Asia, particularly island forms, highly complex, with relationship between present species and O. magicus not fully understood; taxonomic status of races treated under present species unclear, with some or all sometimes treated under O. magicus, and current arrangement tentative. In particular, siaoensis, with shorter wings and much shorter and more narrowly barred tail may well be specifically distinct; sulaensis morphologically closer to O. magicus and probably better placed with that species, or perhaps specifically distinct; mendeni and kalidupae little known. Pending further research, five subspecies recognized.