New insights into the taxonomy of the Hylaeus xanthostoma complex and further additions to the African Hylaeus fauna (Hymenoptera, Anthophila, Colletidae)

Within the genus Hylaeus subgenus Deranchylaeus, from sub-Saharan Africa, a distinctive new subgroup of species is established. The females of this subgroup share a striking character: the orange-coloured lower face, previously known only in H. xanthostoma. The inter-specific differences are cryptic in both sexes. Seven species are newly described: Hylaeus (Deranchylaeus) aurantiacussp. nov. ♀♂, H. (D.) burundissp. nov. ♂, H. (D.) lyriformissp. nov. ♂, H. (D.) sambiensissp. nov. ♂, H. (D.) portokaliussp. nov. ♂♀, H. (D.) diastictussp. nov. ♂ and H. (D.) jemeniticussp. nov. ♀. This subgroup also includes H. (D.) promontorii (Meade-Waldo, 1923) and H. (D.) venustus Dathe, 2014, whose females are described for the first time. From Cameroon, the male of a second species of the subgenus Pumilaeus is described as new: H. (Pumilaeus) soukontouaisp. nov. New records of species of the genus Hylaeus F. in sub-Saharan Africa are added and a revised identification key to the subgenus Deranchylaeus is presented, to include the new species.