Subspecies, varieties, forms and cultivars of plants belonging to the Crassula tetragona group

• Crassula tetragona L.: (subsp. tetragona) is repeatedly branched, with flattish leaves and distinct leaf sheaths (1-2 mm long); the inflorescence is flat-topped with flowers densely clustered. Distribution: S-W Cape mountains.
• Crassula tetragona subs. acutifolia (Lamarck) Toelken: is prostrate and roots at the nodes. Distribution: Rivers-dale to King William's Town.
• Crassula tetragona subs. connivens (Schönland) Toelken: has papillose stems, becoming thick, fleshy or woody when old. The inflorescence is round-topped, almost sessile and usually without bracts. Distribution: Little and Great Karoo.
  
• Crassula tetragona subs. lignescens Toelken: has erect, wiry, woody branches up to 800 mm tall, very short leaf sheaths and 0-1 pairs of sterile bracts on the peduncle. Distribution: Montagu to Grahamstown and also in Namaqualand.
  
• Crassula tetragona subs. robusta (Toelken) Toelken: has thick fleshy stems, the leaves blunt, upward-curving and longer than 20 mm. Peduncle with 0-1 pairs of sterile bracts. Distribution: Eastern Cape river valleys
• Crassula tetragona subs. rudis (Schönland & Baker f.) Toelken: is sparingly branched, and the inflorescence is irregularly branched. It is very similar to subsp. tetragona, but has fleshy roots. Distribution: Namaqualand.