There has been a reassessment of the taxonomic status of Icterine Greenbul (Phyllastrephus icterinus) and Liberian Greenbul (Phyllastrephus leucolepis).
Phyllastrephus icterinus (HBW and BirdLife International 2017) was previously split as Icterine Greenbul P. icterinus and Liberian Greenbul P. leucolepis (del Hoyo and Collar 2016), but P. leucolepis is now considered a junior synonym of P. icterinus. This follows analysis by Collinson et al. (2017) who showed that leucolepis falls within the range of intraspecific genetic variation observed in icterinus and most likely represents a plumage variant of it.
Collinson, J. M.; Päckert, M.; Lawrie, Y.; Gatter, W.; Töpfer, T.; Phalan, B.; Fishpool, L. 2017. Taxonomic status of the Liberian Greenbul Phyllastrephus leucolepis and the conservation importance of the Cavalla Forest, Liberia. J. Ornithol. DOI 10.1007/s10336-017-1477-0.
del Hoyo, J.; Collar, N. J. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.