﻿AbstractA diagnosis is presented for theCentrioncinae, the Afromontane Forest Flies or stalklessDiopsidae, while its taxonomic position within theDiopsidaeis discussed. Arguments are presented for an eventual raising of theCentrioncinaeto family level. The differential characters for its two genera,CentrioncusSpeiser andTeloglabrusFeijen, are tabulated. The diagnosis forCentrioncusis updated and a key to the ten species now recognised (including three new species) is provided.Centrioncuscrassifemursp. nov.is described from a single female from Angola. This greatly extends the distribution range for the genus.Centrioncusbururiensissp. nov.is described from Burundi, whileCentrioncuscopelandisp. nov.originates from the Kasigau Massif of Kenya. Diagnoses, descriptive updates, illustrations and notes are presented for all otherCentrioncus.CentrioncusaberransFeijen, described from Uganda, is now also recorded for western Kenya, Rwanda, and possibly eastern DR Congo. This wide range ofC.aberransis unusual for theCentrioncinaespecies which have allopatric and usually very restricted distribution ranges. Defining characters ofC.aberransfrom the various regions were examined in detail, but only minor differences were found.CentrioncusdecoronotusFeijen, described from Kenya, is now recorded for several other places in Kenya. A distribution map is given for the Eastern AfricanCentrioncusspecies. The eastern branch of the Great Rift Valley appears to form a barrier betweenC.aberransandC.decoronotus. The type species of the genus,C.prodiopsisSpeiser from the Kilimanjaro in Tanzania, was only known from the 1905–1906 type series. After more than 100 years it has now been found again on the Kenya side of Kilimanjaro. Various differential characters ofCentrioncusandDiopsidaeare discussed, while brief discussions on sex ratio and fungal parasites are given.Centrioncusare known to occur on low shrubs and herbaceous plants in rain forests. Now, the possibility is indicated that they also might occur higher up in the tree canopies.