The classification of the three subgenera within the genus Haworthia is based on the floral structure.  The flower of the Hexangularis always looks to me quite "orchid-like".  A cross-section of this flower's base would show a hexangular (six-sided) or rounded-hexangular shape.  These are the hard leaved Haworthias, like attenuata, faciata, and scabra.  With 16 species, this subgenus is less than half the size of the subgenus Haworthia.  When Haworthia bruynsii was discovered in 1981 it appeared to be a retuse type Haworthia until it bloomed.  Then it was seen that it had the Hexangularis flower, so became the first "retuse-type" Haworthia to become a member to the Hexangularis!

The seed pods (fruits) of this subgenus are very close in appearance and structure to the subgenus Haworthia, as are the seeds.  The pods shown here are the size of a large grain of rice, and the seeds are packed inside, with 6 to 30 seeds per pod.  The seeds themselves are 1mm long and 0.5mm wide.