C. Pteridophyta

(Pteron : feather, phyton : plant)

Evolutionary Significance:

  • First vascular and true land plants
  • First successful terrestrial plants with true roots, stem, and leaves
  • Only Cryptogams with vascular tissues
  • Age of Pteridophytes:  Late Paleozoic era
  • Diversity: ~400 genera and 11,000 species

General Characteristics:

Feature

Details

Plant Body

Differentiated into true roots, stem, and leaves

Leaf Types

Pinnate (feather-like) leaves; can be small (microphylls) or large (macrophylls)

Growth Pattern

No secondary growth (absence of cambium)

Vascular System

Xylem: tracheids only; Phloem: sieve cells only

Conducting System

Primitive conducting system

Life Cycle

Shows sporophytic and gametophytic stages

Alternation of Generations

Heteromorphic: sporophyte is dominant

Habitats

Moist, shady places; some aquatic, xerophytic, or epiphytic

Sporophyte Features (Dominant Phase):

  • Diploid (2n), dominant, autotrophic, independent
  • Differentiated into root, stem, and leaves
  • Primary root: Short-lived, replaced by adventitious roots
  • Stem: Aerial or underground
  • Leaves: Scaly (Equisetum), simple and sessile (Lycopodium), or large and pinnately compound (Nephrolepis)

Classification of Pteridophytes:

Class

Characteristics

Examples

Psilopsida

Primitive; simple vascular structure

Psilotum

Lycopsida

Club mosses; simple leaves

Selaginella, Lycopodium

Sphenopsida

Horsetails; jointed stem, scale leaves

Equisetum

Pteropsida

True ferns; large compound leaves

Dryopteris, Pteris, Adiantum, Nephrolepis

Diversity of Habitats:

  • Moist and shady:  Majority
  • Aquatic:  Azolla, Marsilea
  • Xerophytic:  Equisetum
  • Epiphytic:  Lycopodium

Economic Importance:

  • Used for medicinal purposes
  • Act as soil binders
  • Many varieties grown as ornamental plants
  • Garden ferns (e.g., Nephrolepis) widely cultivated

Key Distinction:

Pteridophytes, despite being vascular plants with roots, stems, and leaves, are NOT Phanerogams because they  do not produce seeds or flowers—they reproduce through spores.

 

 

 1. Distinguish between Bryophyta and Pteridophyta.

2. Why Bryophyta are called amphibians of Plant Kingdom?

3. Pteridophytes are also known as vascular Cryptogams - Justify.

4. Give one example of aquatic and xerophytic Pteridophytes.