Does Roystonea or Dionysia have more species?
Roystonea Roystonea is a genus of eleven species of monoecious palms, native to the Caribbean Islands, and the adjacent coasts of Florida and Central and northern South America. Commonly known as the royal palms, the genus was named for Roy Stone, a U.S. Army engineer. It contains some of the most recognizable and commonly cultivated palms in tropical and subtropical regions.
Shirleya Shirleya is an extinct genus in the crape myrtle family, Lythraceae, which contains a single species, Shirleya grahamae. The genus and species are known from Middle Miocene fossils found in Central Washington.