Wikipedia / Magnoliopsida
Wikipedia / Magnoliopsida
Magnoliopsida is a valid botanical name for a class of flowering plants. By definition the class will include the family Magnoliaceae, but its circumscription can otherwise vary, being more inclusive or less inclusive depending upon the classification system being discussed.
Classification
Cronquist and Takhtajan systems
In the Takhtajan system and the Cronquist system, the name was used for the group known as dicotyledons.
The Takhtajan system used this internal taxonomy:
class Magnoliopsida (= dicotyledons)
subclass Magnoliidae
subclass Nymphaeidae
subclass Nelumbonidae
subclass Ranunculidae
subclass Caryophyllidae
subclass Hamamelididae
subclass Dilleniidae
subclass Rosidae
subclass Cornidae
subclass Asteridae
subclass Lamiidae
The Cronquist system used this internal taxonomy (in the 1981 version):
class Magnoliopsida (= dicotyledons)
subclass Magnoliidae
subclass Hamamelidae
subclass Caryophyllidae
subclass Dilleniidae
subclass Rosidae
subclass Asteridae
The Cronquist system has been very popular, and there have been many versions of the system published. In some of these Cronquist-based systems the name Magnoliopsida (at the rank of class) refers to the flowering plants (angiosperms).
Dahlgren and Thorne systems
The Dahlgren system and the Thorne system (1992) used the name Magnoliopsida for the flowering plants.
class Magnoliopsida (= angiosperms)
subclass Magnoliidae (= dicotyledons)
subclass Liliidae (= monocotyledons)
Reveal system
The Reveal system used the name Magnoliopsida for a group of the primitive dicotyledons, corresponding to about half of the plants in the magnoliids:
class 1. Magnoliopsida
superorder 1. Magnolianae
superorder 2. Lauranae
APG systems
In the APG and APG II systems, botanical names are used only at the rank of order and below. Above the rank of order, these systems use their own names, such as angiosperms, eudicots, monocots, rosids, etc. These names refer to clades (unranked). The class Magnoliopsida is not defined. The idea that dicotyledons are a taxonomic unit and require a formal name is rejected by the APG: the dicots are considered to be paraphyletic.
References