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Dicotyledon

Dicotyledons
Scientific classification
Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Orders
Subclass Asteridae
    Asterales (sunflowers) - 1 family
    Callitrichales - 2 families
    Calycerales - 1 family
    Campanulales - 6 families
    Dipsacales - 4 families
    Gentianales - 4 families
    Lamiales - 5 families
    Plantaginales - 1 family
    Polemoniales - 1 family
    Rubiales (madders) - 1 family
    Scrophulariales - 12 families
    Solanales - 7 families
Subclass Caryophyllidae
    Caryophyllales - 12 families
    Plumbaginales - 1 family
    Polygonales - 1 family
Subclass Dilleniidae
    Batales - 1 family
    Capparales - 6 families
    Diapensiales - 1 family
    Dilleniales - 2 families
    Ebenales - 5 families
    Ericales - 7 families
    Lecythidales - 1 family
    Malvales - 6 families
    Nepenthales - 3 families
    Primulalales - 3 families
    Salicales - 1 family
    Theales - 13 families
    Violales[?] - 21 families
Subclass Hamamelidae
    Casuarinales[?] - 1 family
    Fagales - 3 families
    Hamamelidales - 6 families
    Juglandales[?] - 3 families
    Leitneriales[?] - 1 family
    Myricales[?] - 1 family
    Urticales - 6 families
Subclass Hamamelididae
    Daphniphyllales[?] - no families listed
    Didymelales[?] - no families listed
    Eucommiales[?] - 1 family
    Trochodendrales[?] - 2 families
Subclass Magnoliidae
    Aristolochiales - 1 family
    Illiciales - 2 families
    Laurales - 4 families
    Magnoliales - 14 families
    Nymphaeales - 4 families
    Papaverales - 2 families
    Piperales - 3 families
    Ranunculales - 7 families
Subclass Rosidae
    Apiales - 2 families
    Celestrales[?] - 11 families
    Cornales - 5 families
    Euphorbiales - 6 families
    Fabales - 1 family
    Geraniales - 5 families
    Haloragales - 4 families
    Linales[?] - 3 families
    Myrtales - 12 families
    Podostemales[?] - 2 families
    Polygalales[?] - 7 families
    Proteales - 1 family
    Rafflesiales[?] - 3 families
    Rhamnales - 4 families
    Rhizophorales[?] - 1 family
    Rosales - 20 families
    Santalales - 12 families
    Sapindales - 16 families

Dicotyledons are flowering plants whose seeds are divided into two seed lobes, or cotyledons, in germinating. These cotyledons may be ephemeral, lasting only days after emergence, or persistent, lasting a year or more. The name dicot is also used for these plants.

Traditionally the dicots are treated as a class, called the Magnoliopsida or Dicotyledoneae. They are now generally believed to be paraphyletic to the monocotyledons, however, and so some newer systems (e.g. Reveal) divide them. Nearly all fall into a monophyletic group called the eudicots, but this does not include the type genus, Magnolia. Thus in systems which separate them out, the name Rosopsida is used for the eudicots and Magnoliopsida for a basal group.

See also: how to distinguish a monocot from a dicot

Table of contents
1 Reference Links

Synonyms and common names

Synonyms: Dicotyledoneae, Magnoliatae
Common names: Dicotyledons, dicots

Reference

ITIS - Magnoliopsida (as of 2002-05-30) (http://www.itis.usda.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=18063)

Problems

ITIS' classification is somewhat controversial at the moment. There is good reason to expect that many of the groups are para- or polyphyletic, and a number of alternative classifications have arisen.

Sarraceniales - this order is empty in ITIS; its contents appear to now be included in the Nepenthales. Umbellales - this order is empty in ITIS; most of its contents appear to have been moved to the Apiales.

Families with uncertain placement. These families are not mentioned in ITIS. The names mostly result from modern cladistics. Of course, the plants themselves always existed, and are likely already in the taxa listed above, but with a different name that has not yet been identified. They will be moved when enough information is available. A usable chart of families may be found at [1] (http://www.museums.org.za/bio/plants/angiospermae-classif.htm). Description of most of these families may also be found on the Delta site [2] (http://biodiversity.uno.edu/delta/angio/).

  • Berberidopsidaceae[?] - The coral plant of Chile
  • Aphloiaceae[?] - Included in Rosidae by some, Violales by others. See also [3] (http://www.mobot.org/MOBOT/Research/APweb/orders/crossosomatalesweb.htm)
  • Vahliaceae[?] - 1 genus Vahlia or Bistella with 5 species. Included in Rosales by some, Saxifragales by others. See Delta [4] (http://biodiversity.uno.edu/delta/angio/www/vahliace.htm) for more information.
  • Plocospermataceae[?] - 1 genus, 3 species. Variously included in Scrophulariales, Gentianales and Loganiaceae. See Delta [5] (http://biodiversity.uno.edu/delta/angio/www/plocospe.htm).

Reference Links

  1. http://www.museums.org.za/bio/plants/angiospermae-classif.htm
  2. http://biodiversity.uno.edu/delta/angio
  3. http://www.mobot.org/MOBOT/Research/APweb/orders/crossosomatalesweb.htm
  4. http://biodiversity.uno.edu/delta/angio/www/vahliace.htm
  5. http://biodiversity.uno.edu/delta/angio/www/plocospe.htm



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