How are pteridophytes classified?

Pteridophyte

1. Pteripdophytes are the first true land plants.
2. They are also called “cryptograms.”
3. Based on the nature of the leaf and the position of sporangia, they are classified into four classes - psilopsida, lycopsida, sphenopsida, and pteropsida.

Psilopsida:

1. They are the most primitive group of pteridophytes.
2. The plants are dichotomously branched.
3. They have rhizoids, but most of them do not possess leaves.
4. They have a homosporous sporophyte.
5. Example- Psilotum.

Lycopsida:

1. They are also called club mosses.
2. The plant body is differentiated into adventitious roots, stems, rhizophores, and leaves.
3. They can have homosporous and heterosporous sporophytes.
4. Example- Lycopodium

Sphenopsida:

1. They are also called horsetail.
2. The plant body is differentiated into roots, stems, and scaly leaves.
3. The homosporous sporophyte is born on the strobilus.
4. Example- Equisetum.

Pteropsida:

1. They are also called ferns.
2. The plant body is differentiated into roots, stems, and leaves.
3. The sporophyte can be both homosporous and heterosporous.
4. Example- Pteris