18 orders
114 families
58,000 species

Largest subclass in terms of families, tied for largest in terms of number of species

75% of species belong to 5 large orders

1. Fabales
2. Myrtales
3. Euphorbiales
4. Rosales
5. Sapindales

The Rosidae is a very large diverse group of plants. It is difficult to find characteristics which are unique to the Rosidae which would clearly define this subclass

Rosales is the most primitive order and others are thought to be derived from it