This taxon is Not Recognised as a species by BirdLife International.
Merops muelleri (Sibley and Monroe 1990, 1993) has been split into M. muelleri and M. mentalis by the BirdLife Taxonomic Working Group on the basis of significant morphological differences, and genetic analysis in Marks et al.
BirdLife International (2016) Species factsheet: Merops muelleri. Downloaded from http://www.birdlife.org on 03/12/2016. Recommended citation for factsheets for more than one species: BirdLife International (2016) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 03/12/2016.