Asterids

In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade (a monophyletic group). Asterids is the largest group of flowering plant with more than 80,000 species, about a third of the total flowering plant species[1].[2] Well known plants in this clade include the common daisy, forget-me-nots, nightshades (including potatoes, eggplants, tomatoes, peppers and tobacco), the common sunflower, petunias, yacon, morning glory, sweet potato, coffee, lavender, lilac, olive, jasmine, honeysuckle, ash tree, teak, snapdragon, sesame, psyllium, garden sage, table herbs such as mint, basil, and rosemary, and rainforest trees such as Brazil nut.

Asterids
Impatiens capensis (Ericales)
Oregano from Lamiales
Scientific classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Core eudicots
Clade: Superasterids
Clade: Asterids
Clades

Most of the taxa belonging to this clade had been referred to the Asteridae in the Cronquist system (1981) and to the Sympetalae in earlier systems. The name asterids (not necessarily capitalised) resembles the earlier botanical name but is intended to be the name of a clade rather than a formal ranked name, in the sense of the ICBN.

History

Genetic analysis carried out after APG II maintains that the sister to all other asterids are the Cornales. A second order that split from the base of the asterids are the Ericales. The remaining orders cluster into two clades, the lamiids and the campanulids. The structure of both of these clades has changed in APG III.[3][4]

In the APG III system, the following clades were renamed:

euasterids I → lamiids
euasterids II → campanulids[3][4]

Phylogeny

The phylogenetic tree presented hereinafter has been proposed by the APG IV project.[2]

asterids 
 

 Cornales

 
 
 

 Ericales

 
euasterids
campanulids
 

Aquifoliales

 
 
 

Asterales

 
 

Escalloniales

 
 
 

Bruniales

 
 
 

Apiales

 
 
 

Dipsacales

 
 

Paracryphiales

 
 
 
 
 
 
lamiids
 

Icacinales

 
 
 

Metteniusales

 
 
 

Garryales

 
 
 

Boraginales

 
 

Gentianales

 
 

Vahliales

 
 

Lamiales

 
 

Solanales

 
 
 
 
 
 
 
 

Subdivision
lamiids

The lamiid subclade consists of about 40,000 species and account for about 15% of angiosperm diversity, characterized in general by superior ovaries and corollas with any fusion of the petals (sympetaly) occurring late in the process of development. The major part of lamiid diversity occurs in the group of five orders from Boraginales to Solanales, referred to informally as "core lamiids" (sometimes called Laminae), although Vahliales consists of the single small genus Vahlia. The remainder of the lamiids are referred to as "basal lamiids", in which Garryales is the sister group to the core lamiids. It has been suggested that the core lamiids radiated from an ancestral line of tropical trees in which the flowers were inconspicuous and the fruit large, drupaceous and often single-seeded.[5]

References
  1. Bremer, Kåre; Friis, elsemarie; Bremer, birgitta (1 June 2004). "Molecular Phylogenetic Dating of Asterid Flowering Plants Shows Early Cretaceous Diversification". Systematic Biology. 53 (3): 496–505. doi:10.1080/10635150490445913. PMID 15503676.
  2. Angiosperm Phylogeny Group (2016). "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG IV". Botanical Journal of the Linnean Society. 181 (1): 1–20. doi:10.1111/boj.12385.
  3. 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. doi:10.1046/j.1095-8339.2003.t01-1-00158.x.
  4. Angiosperm Phylogeny Group (2009). "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III". Botanical Journal of the Linnean Society. 161 (2): 105–121. doi:10.1111/j.1095-8339.2009.00996.x.
  5. Stull et al 2015.

Bibliography
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