Haworthia mirabilis var. triebneriana is a stemless leaf succulent, a perennial dwarf plant.
The thick, ascending leaves arranged in a ground level rosette are dark green on top from the succulence below the translucent leaf windows. Pale cream lines are present upon these windows like bars, longitudinal and about parallel to the apical area. The leaves taper to acutely pointed tips, their margins toothed, as is the keel on the lower surface. The lower leaf surface is rough from small, white tubercles.
The inflorescence is a simple raceme. Flowering happens early in spring.
The distribution of the variety is within the overall domain of H. mirabilis that grows between Caledon, Bredasdorp and Bonnievale in the Western Cape.
This terrain has hills, flats and some mountains, covered in fynbos or “improvements” added by people. Summers are hot and dry here, the winter rainfall varies between 200 mm to 750 mm. The species grows from elevations of 150 m to 500 m. Whether the variety's habitat population is doing well may be known once the awaited revision of Haworthia is done (https://www.llifle.com; http://redlist.sanbi.org).