Acanthopsis

Abstract: Acanthopsis is a taxonomically poorly understood genus confined to arid parts of southern Africa. This contribution is the first detailed assessment of the diversity within the Acanthopsis disperma-hoffmannseggiana complex, the latter of which comprises the bulk of the specimens of the genus represented in herbaria. Species concepts are resolved and the misapplication of names is noted. In addition to the recognition of A. disperma and A. hoffmannseggiana , five new species of Acanthopsis formerly treated under these two names, are described, namely A. tuba and A. ludoviciana (both confined to the Richtersveld, Northern Cape, South Africa), A. adamanticola (endemic to southern Namibia), A. villosa (endemic to Bushmanland, Northern Cape) and A. dispermoides (endemic to the Western Cape, South Africa). The names A. disperma and A. hoffmannseggiana are lectotypified here. An identification key to the members of the Acanthopsis disperma-hoffmannseggiana complex is provided, as well as an interim key to the major artificial groupings in the genus, the taxonomy of some which still needs to be resolved.

Abstract: Acanthopsis is a poorly understood genus taxonomically, confined to arid parts of southern Africa. The density of the inflorescences and the morphology of the bracts are taxonomically useful characters for species delimitation. This contribution focuses on the taxonomy and conservation status of those members in the genus characterized by semi-dense inflorescences with 5-fid bracts, all of which are confined to arid parts of the Northern Cape Province, South Africa. Six species, A. carduifolia , A . glabra, A. glandulopalmata, A. insueta, A. nitida and A. scullyi, are recognized in this group. Three new species, A. glandulopalmata, A. insueta and A. nitida, are described. An identification key to the species of the group with semi-dense spikes and 5-fid bracts is provided.