Contents

• Introduction to Psilopsida
• Features of Psilopsida
• Life Cycle of Psilopsida
• Final Thoughts

Introduction to Psilopsida

Psilopsida, otherwise known as whisk ferns, is a category of ferns that fall under the division of Tracheophyta. This division consists of two orders - Psilophytales and Psilotales. Initially, Psilopsida was classified under Pteridophytes, but after thorough research by Eames, it was discovered that Psilopsida's vascular system differed significantly from Pteridophytes, leading to the creation of a new division, Tracheophyta.

The division Tracheophyta includes four subdivisions:

1. Psilopsida
2. Lycopsida
3. Sphenopsida
4. Pteropsida

Features of Psilopsida

• These plants do not produce seeds.
• They do not have roots. Instead, they have rhizomes that act as underground stems and hold the sporophyte.
• The shoots grow upwards and divide into smaller stems.
• The rhizomes feature rhizoids, hair-like structures that absorb water and nutrients.
• Their vascular system is basic, primitive, and protostelic.
• They rarely have leaves, and when present, they look like scaly appendages or foliage leaves.
• The plant grows in a sporophyte form.
• They do not undergo secondary growth .

Life Cycle of Psilopsida

• Sporangia, which carry spores, are located on the aerial leaf-like appendages.
• The spore mother cell produces the spores meiotically in groups of four.
• The spores are released from the plant and germinate in moist soil.
• The spores develop into a tiny, colorless gametophyte.
• The gametophyte produces archegonia and antheridia.
• Fertilization of the egg and sperm occurs through water.
• The resulting zygote grows into a new sporophytic body.

Read more about: Pteridophytes

Final Thoughts

The classification and nomenclature of Psilopsida are continuously being updated and revised.

Discover more about plants and their unique features here .