Phylogeny The consensus
phylogenetic tree used in the
APG IV system shows that the group traditionally treated as the dicots is
paraphyletic to the monocots: }}
Historical Traditionally, the dicots have been called the Dicotyledones (or
Dicotyledoneae), at any rank. If treated as a class, as they are within the
Cronquist system, they could be called the Magnoliopsida after the
type genus Magnolia. In some schemes, the eudicots were either treated as a separate
class, the
Rosopsida (type genus
Rosa), or as several separate classes. The remaining dicots (
palaeodicots or basal angiosperms) may be kept in a single
paraphyletic class, called
Magnoliopsida, or further divided. Some botanists prefer to retain the dicotyledons as a valid class, arguing its practicality and that it makes evolutionary sense.
APG vs. Cronquist The following lists show the orders in the Angiosperm Phylogeny Group
APG IV system traditionally called dicots, together with the older
Cronquist system.
Dahlgren and Thorne systems Under the Dahlgren and Thorne systems, the
subclass name
Magnoliidae was used for the dicotyledons. This is also the case in some of the systems derived from the Cronquist system. These two systems are contrasted in the table below in terms of how each categorises by superorder; note that the sequence within each system has been altered in order to pair corresponding taxa. The
Thorne system (1992) as depicted by Reveal is: There exist variances between the superorders
circumscribed from each system. Namely, although the systems share common names for many of the listed superorders, the specific list orders classified within each varies. For example, Thorne's
Theanae corresponds to five distinct superorders under Dahlgren's system, only one of which is called
Theanae. ==See also==