Nesocodon is a monotypic genus of flowering plants within the family Campanulaceae.
 The sole species is Nesocodon mauritianus, formerly known as "Wahlenbergia mauritiana", which is endemic to the island of Mauritius.
Horminum is a genus of flowering plants in the family Lamiaceae, comprising a single species, Horminum pyrenaicum.
 Common names include Dragonmouth and Pyrenean Dead-nettle.
Wahlenbergia is a genus of between 150–270 species of flowering plants in the family Campanulaceae, with a cosmopolitan distribution except for North America; the highest species diversity is in Africa and Australasia.
 "Wahlenbergia" species have dispersed widely, even to oceanic islands, and there are four species known from the island of Saint Helena, including the now extinct species "W. roxburghii".
 The genus was named after Göran Wahlenberg (a Swedish botanist who taught at Uppsala University) by German botanist H. A. Schrader (Heinrich Schrader), in 1814.

Question: Which genus has more species, Wahlenbergia or Horminum?
Answer: Wahlenbergia