PlantDiversity on emsenn.net

Angiosperm

Thu, 02 Apr 2026 00:00:00 +0000

Angiosperm: a flowering plant, member of the clade Angiospermae (formerly Magnoliophyta). With approximately 300,000 described species across 416 families and 64 orders, angiosperms are the dominant land plants and have shaped terrestrial ecosystems for the past 130 million years. The name encodes the defining innovation: angio (vessel) + sperm (seed), referring to the enclosed ovule — the central reproductive novelty that distinguishes angiosperms from gymnosperms, which bear naked seeds.

The angiosperm lineage is monophyletic, originating in the Early Cretaceous. Modern classification follows the Angiosperm Phylogeny Group (APG) framework, now in its fourth iteration (APG IV, 2016), which reorganizes the traditional Linnaean hierarchy on the basis of molecular phylogenetics. The two largest clades are the monocots (~70,000 species) and the eudicots (~210,000 species), which together comprise >99% of angiosperm diversity.

Eudicot

Thu, 02 Apr 2026 00:00:00 +0000

Eudicot: a flowering plant with two cotyledons (seed leaves), one of the two major clades of angiosperms. With approximately 210,000 species, eudicots represent the vast majority of angiosperm diversity and include most familiar flowering plants and trees. The term “eudicot” (true dicot) replaces the older, paraphyletic category “dicot,” which included both eudicots and several basal angiosperm lineages that molecular phylogenetics has now shown to be more distantly related.

Eudicots are characterized by a constellation of anatomical features: two cotyledons in the seed, net-like (reticulate) leaf venation with a prominent midvein and secondary branches, vascular bundles arranged in a ring within the stem (a geometry that enables secondary growth), flower parts typically in fours, fives, or multiples thereof, a taproot system (one primary root with lateral branches), and, in many species, the capacity for secondary growth via a vascular cambium that produces wood.

Monocot

Thu, 02 Apr 2026 00:00:00 +0000

Monocot: a flowering plant with a single cotyledon (seed leaf), one of the two major clades of angiosperms. Monocots comprise approximately 70,000 species and dominate grasslands, wetlands, and tropical canopies. They are identified by a suite of anatomical characters that reflect their monophyletic origin: parallel leaf venation (veins running parallel to the leaf axis), scattered vascular bundles throughout the stem (not arranged in a ring), flower parts typically arranged in threes or multiples of three, fibrous root systems (many similarly sized roots rather than a central taproot), and absence of secondary growth (monocots do not produce wood and cannot form annual rings).