magnoliopsida

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magnoliopsida

A student examines a magnoliopsida leaf under a classroom microscope.

Definition

Noun A major class of flowering plants (angiosperms) characterized by embryos with two seed leaves (cotyledons), leaves with a network of veins, and flower parts typically in multiples of four or five. This class includes a vast majority of broad-leaved trees, shrubs, and herbs.

Examples of Usage
  • The oak, rose, and sunflower are all members of the Magnoliopsida.
  • Botanists study the evolutionary relationships within the Magnoliopsida.
  • The defining feature of Magnoliopsida is the presence of two cotyledons in the seed embryo.
Advanced Usage
  • In some taxonomic systems, Magnoliopsida is synonymous with the term "dicotyledons" or "dicots." However, modern phylogenetic studies show that the traditional grouping of dicots is not monophyletic (does not include all descendants of a common ancestor), as some early-diverging dicot lineages are now placed separately.
  • The class is historically divided into several subclasses, though these groupings are not always clearly distinct.
Variants and Related Words
  • Dicotyledonae (noun): A former taxonomic name for the same group of plants, often used synonymously with Magnoliopsida.
  • Dicot (noun, informal): A common abbreviation for dicotyledon, referring to any plant in this class.
  • Magnoliid (noun/adjective): Pertaining to the subclass Magnoliidae, a primitive group within the Magnoliopsida.
Synonyms
  • Dicotyledons
  • Dicots (informal)
Notes on Different Meanings
  • The term Magnoliopsida is used strictly in botanical taxonomy. It does not have general, non-scientific meanings.
  • It is contrasted with Liliopsida (monocotyledons), the other major class of flowering plants, which typically have one cotyledon, parallel leaf veins, and flower parts in multiples of three.
magnoliopsida

A student examines a magnoliopsida leaf under a classroom microscope.

Noun
  1. comprising seed plants that produce an embryo with paired cotyledons and net-veined leaves; divided into six (not always well distinguished) subclasses (or superorders): Magnoliidae and Hamamelidae (considered primitive); Caryophyllidae (an early and distinctive offshoot); and three more or less advanced groups: Dilleniidae; Rosidae; Asteridae