This taxon is Not Recognised as a species by BirdLife International.
Trachylaemus purpuratus, T. goffinii and T. togoensis (del Hoyo and Collar 2014) were previously placed in the genus Trachyphonus and lumped as Trachyphonus purpuratus following Sibley and Monroe (1990, 1993).
BirdLife International (2016) Species factsheet: Trachyphonus purpuratus. Downloaded from http://www.birdlife.org on 04/12/2016. Recommended citation for factsheets for more than one species: BirdLife International (2016) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 04/12/2016.