Pronunciation key ( dī′kot-ʼl-e′dʼn ) |
di•cot•y•le•don
n.
A plant that produces two seed leaves (cotyledons). Any plant that is classed among one of the two subclasses of seed plants characteristically having two embryos with two cotyledons as most shrubs and deciduous trees.
Terms once used to classify species become outdated and are replaced as classification systems become more accurate. Currently, as it stands, the term Dicotyledoneae, (Taxonomic Serial No.: 206968) is invalid. The accepted name is Magnoliopsida.
| Taxonomic Hierarchy | |
| Kingdom | Plantae – Vegetal, plants |
| Subkingdom | Viridaeplantae – green plants |
| Infrakingdom | Streptophyta – land plants |
| Division | Tracheophyta – vascular plants, tracheophytes |
| Subdivision | Spermatophytina – spermatophytes, seed plants |
| Infradivision | Angiospermae – flowering plants, angiosperms |
| Class | Magnoliopsida |
| Direct Children: | |
| Superorder | Amborellanae |
| Superorder | Asteranae |
| Superorder | Austrobaileyanae |
| Superorder | Berberidopsidanae |
| Superorder | Buxanae |
| Superorder | Caryophyllanae |
| Superorder | Ceratophyllanae |
| Superorder | Dillenianae |
| Superorder | Lilianae – monocots, monocotyledons |
| Superorder | Magnolianae |
| Superorder | Myrothamnanae |
| Superorder | Nymphaeanae |
| Superorder | Proteanae |
| Superorder | Ranunculanae |
| Superorder | Rosanae |
| Superorder | Santalanae |
| Superorder | Saxifraganae |
| Superorder | Trochodendranae |
Historically, dicotyledon were classed as such,
Subclass Dicotyledonae: the dicots. Flower parts are usually in fours or fives; leaf venation is usually netlike, pinnate, or palmate; there is true secondary growth with vascular cambium commonly present; there are two cotyledons; vascular bundles in the stem are in a ring; pollen is basically tricolpate. There are about 190,000 species.
Subclass Monocotyledonae: the monocots. Flower parts are usually in threes; leaf venation is usually parallel; true secondary growth is not present; there is one cotyledon; vascular bundles in the stem are scattered; the pollen is basically monocolpate. There are about 60,000 species.
Source: Biology of Plants, p. 660, Appendix C, ©1970, Worth Publishers, Inc., Peter H. Raven, Helena Curtis, Stanford University
di•cot•y•le•don•ous ( dī′kot-ʼl-e′dʼn-əs )
( dī-kot′ʼl-ed'n-əs )
adj.
Possessing two cotyledons and belonging to the subclass of dicotyledons.
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