Tracheophytes

(Greek ‘trachea’ = windpipe, ‘phyta’ = plant).
Phylum Tracheaphyta.
These are vascular plants.

Vascular plants without seeds

Groups include:

• fork ferns (Psilopsids)

• club mosses (Lycopods)

• horsetails

• ferns

Fossils evidence suggests that some groups formed dominant flora in the past. Today ferns are prominent in some cool, moist areas.

- direct descendants of earliest land plants; fossils of their relatives are 410 million years old (late Silurian period)

- Terrestrial or epiphytic

- instead of roots have rhizomes (underground stems with many rhizoids)

- forked stems with very simple vascular tissue

- spore cases form at tips of short branchs

- only two genera known

Club mosses (e.g. Huperzia species)

(previously known as Lycopodium species)

- prostrate, branching stem with upright branches

- simple vascular systems

- spore-bearing leaves arranged in cones in some species

- motile sperm (male gametes)

Horsetails

- roots, jointed stems and small leaves arranged in a circle around each stem joint

- spore cases resembling cones found on stems

- motile sperm

- today found only in the Northern Hemisphere

- fossil horsetails, Phyllotheca, found in Australia in rocks of Permian period

Ferns

- rhizomes (underground stem), roots and leaves

- vascular tissue grouped in strands (bundles)

- leaves bear spores in sporangia

- gametophyte is heart-shaped, small, green and completely independent

- motile sperm

for details in reproduction of ferns see separate sheet

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