Angiosperm Phylogeny Group

• Commonly known as APG, the Angiosperm Phylogeny Group was formed by an international group of botanists in 1998. This group has published three versions of their classification system: APG (1998), APG II (2003) and APG III (2009). The classification of flowering plants in APG is based on the plant's phylogeny rather than the plants morphology -- the way the plant grows. The most top level classifications for scientific names in the APG system are order and family. The current APG system (APG III) has 59 orders and 415 families.