Burundi (B), Congo [The Democratic Republic of the] (B), Kenya (B), Malawi (B), Mozambique (B), Rwanda (B), Tanzania [United Republic of] (B), Uganda (B), Zambia (B).
Extreme south-eastern Nigeria (Mt Gangirwal, Gotel Mts and Obudu Plateau) and western Cameroon (Tchabal Mbabo and Bamenda Highlands south to Mt Cameroon).
 
Population
Estimated population is unknown (2011).
Mountain Greenbul (Arizelocichla nigriceps) [XC429820]
by Rolf A. de By from Magamba Forest, Mazumbai Forest Reserve, Tanga, Tanzania (song)
Mountain Greenbul (Arizelocichla nigriceps) [XC760165]
by Frank Lambert from Ngorongoro crater rim, Arusha Region, Tanzania (call)
Subspecies
Often treated as forming a superspecies with, or conspecific with, Western Mountain Greenbul (Arizelocichla tephrolaema), but differs in plumage and, especially, voice. Recent studies indicate that Western Mountain Greenbul (Arizelocichla tephrolaema) is more closely allied with subspecies kungwensis of Shelley's Greenbul (Arizelocichla masukuensis) of which was originally described under Western Mountain Greenbul (Arizelocichla tephrolaema) (then considered conspecific with present species). Subspecies chlorigula sometimes considered a separate species. Phylogenetic analysis suggests that northern subspecies (nominate, kikuyuensis, usambarae) form a clade only rather distantly related to southern forms (chlorigula, neumanni, fusciceps) and, further, that relationships within latter group may not be very close. Additionally of the forms tested, the northern subspecies appeared to be more closely related to Stripe-cheeked Greenbul (Arizelocichla milanjensis) (of subspecies striifacies) than to southern subspecies of present species, although support for this relationship was not statistically significant. These findings, different from those inferred from morphological studies, have resulted in proposals for elevation of some or, indeed, all subspecies to species level.
The following 7 subspecies are recognised:
kikuyuensis (Shelley, 1890) - Eastern DRCongo (Ruwenzoris south to Mt Kabobo), south-western and south-eastern Uganda, Rwanda, Burundi, and Mt Elgon and central Kenya Highlands. Considered by some authors to be a distinct species, Olive-breasted Greenbul (Arizelocichla kikuyuensis).
nigriceps (Shelley, 1890) - Southern Kenya (Nguruman) and adjacent northern Tanzania (Mt Kilimanjaro and Crater Highlands south to Mbulu and Mt Hanang).
usambarae (Grote, 1919) - South-eastern Kenya (Taita Hills) and north-eastern Tanzania (southern Pare and western Usambara Mts).
chlorigula (Reichenow, 1899) - Esst-central and southern Tanzania. Considered by some authors to be a distinct species, Yellow-throated Mountain Greenbul (Arizelocichla chlorigula).
neumanni (Hartert, 1922) - Eastern Tanzania (Uluguru Mts). Considered by some authors to be a distinct species, Uluguru Mountain Greenbul (Arizelocichla neumanni).
fusciceps (Shelley, 1893) - South-western Tanzania to north-eastern Zambia, Malawi and west-central Mozambique. Considered by some authors to be a distinct species, Southern Mountain Greenbul (Arizelocichla fusciceps).
kungwensis (Moreau, 1941) - Kungwe-Mahari Mts, in western Tanzania. Considered by some authors to be a subspecies of Kakamega Greenbul (Andropadus kakamegae). Considered by some authors to be a subspecies of Shelley's Greenbul (Arizelocichla masukuensis).