APG IV system

The APG IV system of flowering plant classification is the fourth version of a modern, mostly molecular-based, system of plant taxonomy for flowering plants (angiosperms) being developed by the Angiosperm Phylogeny Group (APG). It was published in 2016, seven years after its predecessor the APG III system was published in 2009, and 18 years after the first APG system was published in 1998.[1] In 2009, a linear arrangement of the system was published separately;[2] the APG IV paper includes such an arrangement, cross-referenced to the 2009 one.[1]

Compared to the APG III system, the APG IV system recognizes five new orders (Boraginales, Dilleniales, Icacinales, Metteniusales and Vahliales), along with some new families, making a total of 64 angiosperm orders and 416 families.[1] In general, the authors describe their philosophy as "conservative", based on making changes from APG III only where "a well-supported need" has been demonstrated. This has sometimes resulted in placements that are not compatible with published studies, but where further research is needed before the classification can be changed.[3]

Short version

Detailed version

Key to symbols used:

* = the family has been added or its circumscription changed since the APG III system of 2009
† = the order has been added since the APG III system

Basal angiosperms

Magnoliids

Independent lineage: unplaced to more inclusive clade

Monocots

Probable sister of eudicots

Eudicots

Core eudicots

Superrosids

Rosids

COM clade; placement uncertain

Rosids continued

Superasterids

Asterids

Phylogeny

Like the earlier APG systems, the APG IV revision is based on a phylogenetic tree for the angiosperms, as shown below.[4]

angiosperms

Amborellales




Nymphaeales




Austrobaileyales



magnoliids


Magnoliales



Laurales





Piperales



Canellales





Chloranthales



monocots

Acorales




Alismatales




Petrosaviales





Pandanales



Dioscoreales





Liliales




Asparagales




Arecales




Poales




Commelinales



Zingiberales













Ceratophyllales


eudicots

Ranunculales




Proteales




Trochodendrales




Buxales




Gunnerales



superrosids

Saxifragales


rosids

Vitales



fabids

(continued)


malvids

(continued)






Dilleniales


superasterids

Berberidopsidales




Santalales




Caryophyllales


asterids

Cornales




Ericales



campanulids

(continued)


lamiids

(continued)




















fabids

Zygophyllales





Fabales




Rosales




Fagales



Cucurbitales







Celastrales




Malpighiales



Oxalidales






malvids


Geraniales



Myrtales





Crossosomatales




Picramniales




Sapindales




Huerteales




Brassicales



Malvales








campanulids

Aquifoliales




Asterales



Escalloniales




Bruniales




Apiales




Dipsacales



Paracryphiales







lamiids

Icacinales




Metteniusales




Garryales




Boraginales



Gentianales



Vahliales



Lamiales



Solanales






References

Bibliography

This article is issued from Wikipedia - version of the 10/30/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.