APG II system

A modern system of plant taxonomy, the APG II system of plant classification was published in April of 2003 by the Angiosperm Phylogeny Group, APG. It was a revision of the first APG system, published in 1998, and was superseded in 2009 by a further revision, the APG III system. APG II was published as:

Each of the APG systems represents the broad consensus of a number of systematic botanists, united in the APG, working at several institutions worldwide.

The APG II system recognized 45 orders, five more than the APG system. The new orders were Austrobaileyales, Canellales, Gunnerales, Celastrales, and Crossosomatales. APG II also recognized 457 families, five fewer than the APG system. Thirty-nine of the APG II families were not placed in any order, but 36 of the 39 were placed in some supra-ordinal group within the angiosperms. Fifty-five of the families came to be known as "bracketed families". They were optional segregates of families that could be circumscribed in a larger sense.

The APG II system was influential and was adopted in whole or in part (sometimes with modifications) in a number of references. It was superseded 6½ years later by the APG III system, published in October of 2009.

Main groups in the system (all unranked clades between the ranks of class and order):

Shown below is the classification in full detail, except for the fifteen genera and three families that were unplaced in APG II. The unplaced taxa were listed at the end of the appendix in a section entitled "Taxa of Uncertain Position". Under some of the clades are listed the families that were placed incertae sedis in that clade. Thirty-six families were so placed. This means that their relationship to other members of the clade is not known.

Note: "+ ..." = optionally separate family, that may be split off from the preceding family.

Cladogram

A cladogram showing the relationships, but excluding taxa not placed within an order