• An undescribed name for a Madagascan species found growing on gneiss scree;
  
• Shoots shortly hairy;
  
• Flowers. minute, white;
  
• Fruit. greenish, mostly smooth, more rarely bristly;
  
• Seed. black. Extraordinarily free-flowering.
  

R. madagascarensis Weber, a similar plant, was described as having white fruit and brown seeds; i.e. Weber correctly saw the plants as two distinct species.