By Bruce Bayer concept
A. The subgenus Haworthia
B. The subgenus Hexangularis
attenuata | bruynsii | coarctata |
fasciata | glabrata | glauca |
koelmaniorum | limifolia | longiana |
nigra | pungens | reinwardtii |
scabra | sordida | venosa |
viscosa |
C. The subgenus Robustipedunculares
kingiana | marginata | minima |
pumila |