Tracheophyte Evolution

Origin Big split between

Lycophyte lineage and Euphyllophytes

Euphyllophytes have megaphylls, pseudomonopodial growth

Next Big Split Monilophytes (ferns

and fern allies, including horsetails) and Lignophytes

Monilophytes: Multiflagellate sperm; reproduction by spores; many functional megaspores; stellar anatomy; chloroplast inversion.

Lignophytes Progymnosperms,

Seed Ferns, Gymnosperms, and Flowering plants

Secondary xylem and phloem, cambial ring; heterospory.

Seed plants 1 functional megaspore;

integument around megasporangium; seeds; pollen grains.

Radiation (= who knows order) into Genophytes, Conifers, Ginkgo, cycads and ANGIOSPERMS

Angiosperms Seeds in carpels; stigmatic

surface; megagametophyte of 8 nuclei; double fertilization

Closest ancestor – shifting ideas

Basal Angiosperm Evolution

Vessels after Amborella

Diploid endosperm

Carpels sealed by secretion

And then …. Postgenital fusion

of carpel epidermes

Carpel primordium is U-shaped

Radiation – Magnoliids, ?? Monocots, Eudicots

Monocots Scattered vascular

bundles; no vascular cambium; leaf blade from base of primordium; one cotyledon

About half the monocots are orchids (19,500) or grasses (10,000)

Poales

Monocots