This taxon is Not Recognised as a species by BirdLife International.
Ceyx fallax and C. sangirensis (del Hoyo and Collar 2014) were previously lumped as C. fallax following Sibley and Monroe (1990, 1993).
BirdLife International (2016) Species factsheet: Ceyx fallax. Downloaded from http://www.birdlife.org on 05/12/2016. Recommended citation for factsheets for more than one species: BirdLife International (2016) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 05/12/2016.