# APG II system

The APG II system (Angiosperm Phylogeny Group II system) of plant classification is the second, now obsolete, version of a modern, mostly molecular-based, system of plant taxonomy that was published in April 2003 by the Angiosperm Phylogeny Group. It was a revision of the first APG system, published in 1998, and was superseded in 2009 by a further revision, the APG III system.

## History

APG II was published as:
* Angiosperm Phylogeny Group (2003). "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG II". Botanical Journal of the Linnean Society 141(4): 399-436. (Available online: Abstract | Full text (HTML) | Full text (PDF) doi: 10.1046/j.1095-8339.2003.t01-1-00158.x)
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, all of which were families unplaced as to order, although contained in supra-ordinal clades, in the APG system. APG II 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 a supra-ordinal clade 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 It was superseded 6½ years later by the APG III system, published in October 2009.

## Groups

Main groups in the system (all unranked clades between the ranks of class and order):
* angiosperms :
    magnoliids
    monocots
       commelinids
    eudicots
       core eudicots
          rosids
             eurosids I
             eurosids II
          asterids
             euasterids I
             euasterids II
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.
* angiosperms :
    paraphyletic grade basal angiosperms
          family Amborellaceae
          family Chloranthaceae
          family Nymphaeaceae [+ family Cabombaceae]
       order Austrobaileyales
       order Ceratophyllales
    clade magnoliids
          order Canellales
          order Laurales
          order Magnoliales
          order Piperales
    clade monocots
             family Petrosaviaceae
          order Acorales
          order Alismatales
          order Asparagales
          order Dioscoreales
          order Liliales
          order Pandanales
       clade commelinids
                family Dasypogonaceae
             order Arecales
             order Commelinales
             order Poales
             order Zingiberales
    clade eudicots
             family Buxaceae [+ family Didymelaceae]
             family Sabiaceae
             family Trochodendraceae [+ family Tetracentraceae]
          order Proteales
          order Ranunculales
       clade core eudicots
                family Aextoxicaceae
                family Berberidopsidaceae
                family Dilleniaceae
             order Gunnerales
             order Caryophyllales
             order Santalales
             order Saxifragales
          clade rosids
                   family Aphloiaceae
                   family Geissolomataceae
                   family Ixerbaceae
                   family Picramniaceae
                   family Strasburgeriaceae
                   family Vitaceae
                order Crossosomatales
                order Geraniales
                order Myrtales
             clade eurosids I
                      family Zygophyllaceae [+ family Krameriaceae]
                      family Huaceae
                   order Celastrales
                   order Cucurbitales
                   order Fabales
                   order Fagales
                   order Malpighiales
                   order Oxalidales
                   order Rosales
             clade eurosids II
                      family Tapisciaceae
                   order Brassicales
                   order Malvales
                   order Sapindales
          clade asterids
                order Cornales
                order Ericales
             clade euasterids I
                      family Boraginaceae
                      family Icacinaceae
                      family Oncothecaceae
                      family Vahliaceae
                   order Garryales
                   order Gentianales
                   order Lamiales
                   order Solanales
             clade euasterids II
                      family Bruniaceae
                      family Columelliaceae [+ family Desfontainiaceae]
                      family Eremosynaceae
                      family Escalloniaceae
                      family Paracryphiaceae
                      family Polyosmaceae
                      family Sphenostemonaceae
                      family Tribelaceae
                   order Apiales
                   order Aquifoliales
                   order Asterales
                   order Dipsacales
Note: "+ ..." = optionally separate family, that may be split off from the preceding family.