PLANTAE - The Embryophytes

First Order of Business: An overview of alternation of generations. And a full explanation of alternation of generations.

A quick "Tiptoe through the Taxa": Meet the Plants. (Indentations indicate that a taxon is included within the non-indented taxon above it.)

• Bryophyta - The Non-vascular Plants
  In Bryophytes, the haploid gametophyte phase is "dominant," living more than one season.
  The diploid sporophyte generation is small and ephemeral.
  • Hepatophyta - the liverworts
  • Anthocerophyta - the hornworts
  • Bryophyta - the mosses

• Tracheophyta - The Vascular Plants In Tracheophytes, the diploid sporophyte phase is dominant, living more than one season;
  the haploid gametophyte generation is small and ephemeral.
  • Lycophyta - The Seedless Vascular Plants
    • Lycophyta - club misses, spike mosses, and quillworts
    • Pterophyta - ferns, horsetails, whisk ferns

  • The Seed-producing Vascular Plants (or just "seed plants")
    • Gymnosperms (the naked seed plants)
      • Cycadophyta - the cycads ("sago palms")
      • Ginkgophyta - maidenhair trees
      • Coniferophyta - the conifers
      • Gnetophyta - the gnetophytes

    • Angiosperms (the flowering plants)
      • Anthophyta
        (a.k.a. Magnoliophyta; (Magnolia is the most primitive of all flowering plants)
        • Dicotyledonae
          (dicots - paraphyletic)
          • leaf veins form a network
          • flower parts in multiples of four or five
          • central taproot with side-branching roots
          • vascular tissue arranged in rings in stem and root
        • Monocotyledonae
          (monocots - a monophyletic lineage branched from one of the many dicot taxa)
          • leaf veins are parallel
          • flower parts in multiples of three
          • fibrous roots; no central taproot
          • vascular tissue arranged in discrete bundles in stem and root

NameNote: The suffix "wort" is from the ancient Anglo Saxon word wyrt meaning "herb".

Little Note on Phylogeny: Anthocerophytes--the hornworts--are believed to be the closest living relatives of the charophyceans. They have stomates that actually open and close, as do those of true plants. Other Bryophytes lack this character.