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. In 2009, a linear arrangement of the system was published separately; the APG IV paper includes such an arrangement, cross-referenced to the 2009 one.

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. 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.

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 Amborellales Melikyan et al. Amborellaceae Pichon, nom. cons. Nymphaeales Salisb. ex Bercht. & J.Presl Hydatellaceae U.Hamann Cabombaceae Rich. ex A.Rich., nom. cons. Nymphaeaceae Salisb., nom. cons. Austrobaileyales Takht. ex Reveal Austrobaileyaceae Croizat, nom. cons. Trimeniaceae Gibbs, nom. cons. Schisandraceae Blume, nom. cons.

Magnoliids Canellales Cronq. Canellaceae Mart., nom. cons. Winteraceae R.Br. ex Lindl., nom. cons. Piperales Bercht. & J.Presl Saururaceae Rich. ex T.Lestib., nom. cons. Piperaceae Giseke, nom. cons. Aristolochiaceae Juss., nom. cons. * (including Asaraceae Vent., Hydnoraceae C.Agardh, nom. cons., Lactoridaceae Engl., nom. cons.) Magnoliales Juss. ex Bercht. & J.Presl Myristicaceae R.Br., nom. cons. Magnoliaceae Juss., nom. cons. Degeneriaceae I.W.Bailey & A.C.Sm., nom. cons. Himantandraceae Diels, nom. cons. Eupomatiaceae Orb., nom. cons. Annonaceae Juss., nom. cons. Laurales Juss. ex Bercht. & J.Presl Calycanthaceae Lindl., nom. cons. Siparunaceae Schodde Gomortegaceae Reiche, nom. cons. Atherospermataceae R.Br. Hernandiaceae Blume, nom. cons. Monimiaceae Juss., nom. cons. Lauraceae Juss., nom. cons.

Independent lineage: unplaced to more inclusive clade Chloranthales Mart. Chloranthaceae R.Br. ex Sims, nom. cons.

Monocots Acorales Mart. Acoraceae Martinov Alismatales R.Br. ex Bercht. & J.Presl Araceae Juss., nom. cons. Tofieldiaceae Takht. Alismataceae Vent., nom. cons. Butomaceae Mirb., nom. cons. Hydrocharitaceae Juss., nom. cons. Scheuchzeriaceae F.Rudolphi, nom. cons. Aponogetonaceae Planch., nom. cons. Juncaginaceae Rich., nom. cons. * Maundiaceae Nakai * Zosteraceae Dumort., nom. cons. Potamogetonaceae Bercht. & J.Presl, nom. cons Posidoniaceae Vines, nom. cons. Ruppiaceae Horan., nom. cons. Cymodoceaceae Vines, nom. cons. Petrosaviales Takht. Petrosaviaceae Hutch., nom. cons. Dioscoreales Mart. Nartheciaceae Fr. ex Bjurzon Burmanniaceae Blume, nom. cons. (not monophyletic.) Dioscoreaceae R.Br., nom. cons. Pandanales R.Br. ex Bercht. & J.Presl Triuridaceae Gardner, nom. cons. Velloziaceae J.Agardh, nom. cons. Stemonaceae Caruel, nom. cons. Cyclanthaceae Poit. ex A.Rich., nom. cons. Pandanaceae R.Br., nom. cons. Liliales Perleb Campynemataceae Dumort. Corsiaceae Becc., nom. cons. Melanthiaceae Batsch ex Borkh., nom. cons. Petermanniaceae Hutch, nom. cons. Alstroemeriaceae Dumort., nom. cons. Colchicaceae DC., nom. cons. Philesiaceae Dumort., nom. cons. Ripogonaceae Conran & Clifford Smilacaceae Vent., nom. cons. Liliaceae Juss., nom. cons. Asparagales Link Orchidaceae Juss., nom. cons. Boryaceae M.W.Chase et al. Blandfordiaceae R.Dahlgren & Clifford Asteliaceae Dumort. Lanariaceae H.Huber ex R.Dahlgren Hypoxidaceae R.Br., nom. cons. Doryanthaceae R.Dahlgren & Clifford Ixioliriaceae Nakai (as 'Ixiolirionaceae'; spelling corrected) Tecophilaeaceae Leyb., nom. cons. Iridaceae Juss., nom. cons. Xeronemataceae M.W.Chase et al. Asphodelaceae Juss., nom. cons. prop. (including Xanthorrhoeaceae Dumort., nom. cons.) Amaryllidaceae J.St.-Hil., nom. cons. Asparagaceae Juss., nom. cons. Arecales Bromhead Dasypogonaceae Dumort. Arecaceae Bercht. & J.Presl, nom. cons. (=Palmae Juss., nom. cons.) Commelinales Mirb. ex Bercht. & J.Presl Hanguanaceae Airy Shaw Commelinaceae Mirb., nom. cons. Philydraceae Link, nom. cons. Pontederiaceae Kunth, nom. cons. Haemodoraceae R.Br., nom. cons. Zingiberales Griseb. Strelitziaceae Hutch., nom. cons. Lowiaceae Ridl., nom. cons. Heliconiaceae Vines Musaceae Juss., nom. cons. Cannaceae Juss., nom. cons. Marantaceae R.Br., nom. cons. Costaceae Nakai Zingiberaceae Martinov, nom. cons. Poales Small Typhaceae Juss., nom. cons. Bromeliaceae Juss., nom. cons. Rapateaceae Dumort., nom. cons. Xyridaceae C.Agardh, nom. cons. Eriocaulaceae Martinov, nom. cons. Mayacaceae Kunth, nom. cons. Thurniaceae Engl., nom. cons. Juncaceae Juss., nom. cons. Cyperaceae Juss., nom. cons. Restionaceae R.Br., nom. cons. * (including Anarthriaceae D.W.Cutler & Airy Shaw, Centrolepidaceae Endl., nom. cons.) Flagellariaceae Dumort., nom. cons. Joinvilleaceae Toml. & A.C.Sm. Ecdeiocoleaceae D.W.Cutler & Airy Shaw Poaceae Barnhart, nom. cons. (= Gramineae Juss., nom. cons.)

Probable sister of eudicots Ceratophyllales Link Ceratophyllaceae Gray, nom. cons.

Eudicots Ranunculales Juss. ex Bercht. & J.Presl Eupteleaceae K.Wilh., nom. cons. Papaveraceae Juss., nom. cons. Circaeasteraceae Hutch., nom. cons. Lardizabalaceae R.Br., nom. cons. Menispermaceae Juss., nom. cons. Berberidaceae Juss., nom. cons. Ranunculaceae Juss., nom. cons. Proteales Juss. ex Bercht. & J.Presl Sabiaceae Blume, nom. cons. Nelumbonaceae A.Rich., nom. cons. Platanaceae T.Lestib., nom. cons. Proteaceae Juss., nom. cons. Trochodendrales Takht. ex Cronq. Trochodendraceae Eichler, nom. cons. Buxales Takht. ex Reveal Buxaceae Dumort., nom. cons. * (including Haptanthaceae C.Nelson)

Core eudicots Gunnerales Takht. ex Reveal Myrothamnaceae Nied., nom. cons. Gunneraceae Meisn., nom. cons. Dilleniales DC. ex Bercht. & J.Presl † Dilleniaceae Salisb., nom. cons.

Superrosids Saxifragales Bercht. & J.Presl Peridiscaceae Kuhlm., nom. cons. Paeoniaceae Raf., nom. cons. Altingiaceae Lindl., nom. cons. Hamamelidaceae R.Br., nom. cons. Cercidiphyllaceae Engl., nom. cons. Daphniphyllaceae Müll.Arg., nom. cons. Iteaceae J.Agardh, nom. cons. Grossulariaceae DC., nom. cons. Saxifragaceae Juss., nom. cons. Crassulaceae J.St.-Hil., nom. cons. Aphanopetalaceae Doweld Tetracarpaeaceae Nakai Penthoraceae Rydb. ex Britton, nom. cons. Haloragaceae R.Br., nom. cons. Cynomoriaceae Endl. ex Lindl., nom. cons.

Rosids Vitales Juss. ex Bercht. & J.Presl Vitaceae Juss., nom. cons.

Fabids

Zygophyllales Link Krameriaceae Dumort., nom. cons. Zygophyllaceae R.Br., nom. cons. Fabales Bromhead Quillajaceae D.Don Fabaceae Lindl., nom. cons. (= Leguminosae Juss., nom. cons.) Surianaceae Arn., nom. cons. Polygalaceae Hoffmanns. & Link, nom. cons. Rosales Bercht. & J.Presl Rosaceae Juss., nom. cons. Barbeyaceae Rendle, nom. cons. Dirachmaceae Hutch. Elaeagnaceae Juss., nom. cons. Rhamnaceae Juss., nom. cons. Ulmaceae Mirb., nom. cons. Cannabaceae Martinov, nom. cons. Moraceae Gaudich., nom. cons. Urticaceae Juss., nom. cons. Fagales Engl. Nothofagaceae Kuprian. Fagaceae Dumort., nom. cons. Myricaceae Rich. ex Kunth, nom. cons. Juglandaceae DC. ex Perleb, nom. cons. Casuarinaceae R.Br., nom. cons. Ticodendraceae Gomez-Laur. & L.D.Gomez Betulaceae Gray, nom. cons. Cucurbitales Juss. ex Bercht. & J.Presl Apodanthaceae Tiegh. ex Takht. * Anisophylleaceae Ridl. Corynocarpaceae Engl., nom. cons. Coriariaceae DC., nom. cons. Cucurbitaceae Juss., nom. cons. Tetramelaceae Airy Shaw Datiscaceae Dumort., nom. cons. Begoniaceae C.Agardh, nom. cons.

COM clade; placement uncertain Celastrales Link Lepidobotryaceae J. Leonard, nom. cons. Celastraceae R.Br., nom. cons. Oxalidales Bercht. & J.Presl Huaceae A.Chev. Connaraceae R.Br., nom. cons. Oxalidaceae R.Br., nom. cons. Cunoniaceae R.Br., nom. cons. Elaeocarpaceae Juss., nom. cons. Cephalotaceae Dumort., nom. cons. Brunelliaceae Engl., nom. cons. Malpighiales Juss. ex Bercht. & J.Presl Pandaceae Engl. & Gilg, nom. cons. Irvingiaceae Exell & Mendonça, nom. cons. * (including Allantospermum Forman) Ctenolophonaceae Exell & Mendonça Rhizophoraceae Pers., nom. cons. Erythroxylaceae Kunth, nom. cons. Ochnaceae DC., nom. cons. Bonnetiaceae L.Beauvis. ex Nakai Clusiaceae Lindl., nom. cons. (= Guttiferae Juss., nom. cons.) Calophyllaceae J.Agardh Podostemaceae Rich. ex Kunth, nom. cons. Hypericaceae Juss., nom. cons. Caryocaraceae Voigt, nom. cons. Lophopyxidaceae H.Pfeiff. Putranjivaceae Meisn. Centroplacaceae Doweld & Reveal Elatinaceae Dumort., nom. cons. Malpighiaceae Juss., nom. cons. Balanopaceae Benth. & Hook.f., nom. cons. Trigoniaceae A.Juss., nom. cons. Dichapetalaceae Baill., nom. cons. Euphroniaceae Marc.-Berti Chrysobalanaceae R.Br., nom. cons. Humiriaceae A.Juss., nom. cons. Achariaceae Harms, nom. cons. Violaceae Batsch, nom. cons. Goupiaceae Miers Passifloraceae Juss. ex Roussel, nom. cons. Lacistemataceae Mart., nom. cons. Salicaceae Mirb., nom. cons. Peraceae Klotzsch * Rafflesiaceae Dumort., nom. cons. Euphorbiaceae Juss., nom. cons. * Linaceae DC. ex Perleb, nom. cons. Ixonanthaceae Planch. ex Miq., nom. cons. * Picrodendraceae Small, nom. cons. Phyllanthaceae Martinov, nom. cons.

Malvids Geraniales Juss. ex Bercht. & J.Presl Geraniaceae Juss., nom. cons. Francoaceae A.Juss., nom. cons. * (including Bersamaceae Doweld, Greyiaceae Hutch., nom. cons., Ledocarpaceae Meyen, Melianthaceae Horan., nom. cons., Rhynchothecaceae A.Juss., Vivianiaceae Klotzsch, nom. cons.) Myrtales Juss. ex Bercht. & J.Presl Combretaceae R.Br., nom. cons. Lythraceae J.St.-Hil., nom. cons. Onagraceae Juss., nom. cons. Vochysiaceae A.St.-Hil., nom. cons. Myrtaceae Juss., nom. cons. Melastomataceae Juss., nom. cons. Crypteroniaceae A.DC., nom. cons. Alzateaceae S.A.Graham Penaeaceae Sweet ex Guill., nom. cons. Crossosomatales Takht. ex Reveal Aphloiaceae Takht. Geissolomataceae A.DC., nom. cons. Strasburgeriaceae Tiegh., nom. cons. Staphyleaceae Martinov, nom. cons. Guamatelaceae S.H.Oh & D.Potter Stachyuraceae J.Agardh, nom. cons. Crossosomataceae Engl., nom. cons. Picramniales Doweld Picramniaceae Fernando & Quinn Huerteales Doweld Gerrardinaceae M.H.Alford Petenaeaceae Christenh. et al. * Tapisciaceae Takht. Dipentodontaceae Merr., nom. cons. Sapindales Juss. ex Bercht. & J.Presl Biebersteiniaceae Schnizl. Nitrariaceae Lindl. Kirkiaceae Takht. Burseraceae Kunth, nom. cons. Anacardiaceae R.Br., nom. cons. Sapindaceae Juss., nom. cons. (including Xanthocerataceae Buerki et al., as 'Xanthoceraceae') Rutaceae Juss., nom. cons. Simaroubaceae DC., nom. cons. Meliaceae Juss., nom. cons. Malvales Juss. ex Bercht. & J.Presl Cytinaceae A.Rich. Muntingiaceae C.Bayer et al. Neuradaceae Kostel., nom. cons. Malvaceae Juss., nom. cons. Sphaerosepalaceae Bullock Thymelaeaceae Juss., nom. cons. Bixaceae Kunth, nom. cons. Cistaceae Juss., nom. cons. * (including Pakaraimaea Maguire & P.S.Ashton) Sarcolaenaceae Caruel, nom. cons. Dipterocarpaceae Blume, nom. cons. * Brassicales Bromhead Akaniaceae Stapf, nom. cons. Tropaeolaceae Juss. ex DC., nom. cons. Moringaceae Martinov, nom. cons. Caricaceae Dumort., nom. cons. Limnanthaceae R.Br., nom. cons. Setchellanthaceae Iltis