The basal angiosperms are the

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

s which diverged from the lineage leading to most flowering plants. In particular, the most basal angiosperms were called the ANITA grade, which is made up of ''

Amborella ''Amborella'' is a monotypic genus of understory shrubs or small trees endemic to the main island, Grande Terre, of New Caledonia in the southwest Pacific Ocean. The genus is the only member of the family Amborellaceae and the order Amborella ...

'' (a single species of shrub from New Caledonia),

Nymphaeales The Nymphaeales are an order of flowering plants, consisting of three families of aquatic plants, the Hydatellaceae, the Cabombaceae, and the Nymphaeaceae (water lilies). It is one of the three orders of basal angiosperms, an early-divergin ...

(water lilies, together with some other aquatic plants) and

Austrobaileyales Austrobaileyales is an order of flowering plants consisting of about 100 species of woody plants growing as trees, shrubs and lianas. A well known example is '' Illicium verum'', commonly known as star anise. The order belongs to the group of b ...

(woody aromatic plants including star anise). ''ANITA'' stands for ''Amborella'', ''N''ymphaeales, ''I''lliciales, ''T''rimeniaceae, and '' Austrobaileya''. Some authors have shortened this to ''ANA''-grade for the three orders, ''A''mborellales, ''N''ymphaeales, and ''A''ustrobaileyales, since the order Iliciales was reduced to the family Illiciaceae and placed, along with the family Trimeniaceae, within the Austrobaileyales. The basal angiosperms are only a few hundred species, compared with hundreds of thousands of species of

eudicots The eudicots or eudicotyledons are flowering plants that have two seed leaves (cotyledons) upon germination. The term derives from ''dicotyledon'' (etymologically, ''eu'' = true; ''di'' = two; ''cotyledon'' = seed leaf). Historically, authors h ...

monocots Monocotyledons (), commonly referred to as monocots, ( Lilianae '' sensu'' Chase & Reveal) are flowering plants whose seeds contain only one embryonic leaf, or cotyledon. A monocot taxon has been in use for several decades, but with various ranks a ...

, and

magnoliids Magnoliids, Magnoliidae or Magnolianae are a clade of flowering plants. With more than 10,000 species, including magnolias, nutmeg, bay laurel, cinnamon, avocado, black pepper, tulip tree and many others, it is the third-largest group of angiospe ...

. They diverged from the ancestral angiosperm lineage before the five groups comprising the mesangiosperms diverged from each other.

Phylogeny

'',

and

, in that order, are basal to all other angiosperms.

Older terms

''Paleodicots'' (sometimes spelled "palaeodicots") is an informal name used by botanists (Spichiger & Savolainen 1997, Leitch et al. 1998) to refer to angiosperms which are not

monocot Monocotyledons (), commonly referred to as monocots, (Lilianae ''sensu'' Chase & Reveal) are flowering plants whose seeds contain only one Embryo#Plant embryos, embryonic leaf, or cotyledon. A monocot taxon has been in use for several decades, but ...

s or

. The paleodicots correspond to Magnoliidae sensu Cronquist 1981 (minus Ranunculales and Papaverales) and to Magnoliidae sensu Takhtajan 1980 (Spichiger & Savolainen 1997). Some of the paleodicots share apparently plesiomorphic characters with monocots, e.g., scattered vascular bundles, trimerous flowers, and non-tricolpate

pollen Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced Gametophyte#Heterospory, microgametophytes), which produce male gametes (sperm ...

. The "paleodicots" are not a monophyletic group and the term has not been widely adopted. The

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 phylogenetics, molecular-based, list of systems of plant taxonomy, system of plant taxonomy that ...

does not recognize a group called "paleodicots" but assigns these early-diverging dicots to several orders and unplaced families: Amborellaceae,

Nymphaeaceae Nymphaeaceae () is a family of flowering plants, commonly called water lilies. They live as rhizomatous aquatic herbs in temperate climate, temperate and tropical climates around the world. The family contains five genera with about 70 know ...

(including Cabombaceae),

Ceratophyllales Ceratophyllaceae is a cosmopolitan family of flowering plants including one living genus commonly found in ponds, marshes, and quiet streams in tropical and in temperate regions. It is the only extant family in the order Ceratophyllales. Species ...

(not included among the "paleodicots" by Leitch et al. 1998),

Chloranthaceae Chloranthaceae ( ) is a family of flowering plants (angiosperms), the only family in the order Chloranthales. It is not closely related to any other family of flowering plants, and is among the early-diverging lineages in the angiosperms. They a ...

, and the magnoliid clade (orders Canellales, Piperales, Laurales, and

Magnoliales The Magnoliales are an order of flowering plants. Well-known members of Magnoliales include: magnolias, Liriodendron, tulip trees, Annona squamosa, custard apples, Asimina triloba, American pawpaw, cherimoyas, Cananga odorata, ylang-ylang, Sours ...

). Subsequent research has added

Hydatellaceae ''Trithuria'' is a genus of small ephemeral aquatic herb that represent the only members of the family Hydatellaceae found in India, Australia, and New Zealand. Almost all described species of ''Trithuria'' are found in Australia, with the exce ...

to the paleodicots. The term ''paleoherb'' is another older term for flowering plants which are neither eudicots nor monocots.

References

External links

tolweb.org
{{Angiosperm orders Angiosperms