Classification of Pteridophyta

Pteridophytes is made up of two words: “pteron,” which means “feather,” and “phyton,” which means “plant.” Plants having feather-like leaves are known as Pteridophytes. Their first traces were discovered in the late paleozoic Silurian epoch. Between bryophytes and spermatophytes, pteridophytes occupy a transitional position. Vascular plants have been split into two groups for a long time: pteridophyta and spermatophyta. The rationale behind this division was that the former lacked seeds while the latter generated them. However, the discovery of pteridophytes (seed-bearing ferns) shattered this artificial categorization.

Pteridophyta

Pteridophytes (ferns and lycophytes) are free-sporing vascular plants having a life cycle that alternates between free-living gametophyte and sporophyte phases that mature to be independent. The anatomy of the sporophyte is neatly split into roots, stems, and leaves. The root system is always in a state of flux. The stem can be found underground or above ground. There are two types of leaves: microphylls and megaphylls. They also have vascular plant apomorphies (e.g., vascular tissue) and land plant plesiomorphies in common (e.g., spore dispersal and the absence of seeds).

Pteridophyta Characteristics

The following are some of the most important characteristics of Pteridophytes.

• They prefer wet, shady environments. Certain species are also able to survive in sandy soils.
• The roots, stem, and leaves of the main plant body are all distinct. It’s known as a sporophyte.
• The stem is a subsurface rhizome.
• Microphylls are little leaves found on some Pteridophytes (e.g., lycopodium) whereas megaphylls are huge leaves found on others (e.g Pteris).
• Spores may be found on the underside of leaves. Such leaves are referred to as sporophylls.
• The plants have no flowers and no seeds. Spores are used to replicate.
• Sporophylls can form cones or strobili, which are compact structures made up of sporophylls.
• The vascular system is well-developed, containing xylem (for water conduction) and phloem (for food conduction).

Pteridophyta classification

Psilopsida

• These are the oldest vascular plants that have been discovered. The majority of them are now extinct. The only two remaining species are Psilotum and Tmesipteris.
• The plant’s body is quite basic and lacks significant differentiation.
• Roots are replaced with a dichotomously branching rhizome.
• Sporangia blooms directly on the stem. It could be either terminal or lateral.

Lycopsida

• The root, stem, and leaves of the plant are differentiated.
• Microphyllous (small) leaves have a single unbranched vein in the midrib.
• Sporangia are produced in the fertile leaves’ axils.
• Sporophyll clumps together to create strobili (singular strobilus).

Sphenopsida

• Like higher vascular plants, the plant body is divided into nodes and internodes.
• Microphyllous leaves that grow in whorls at each node.
• Sporangia form at the apex of fertile branches on sporangiophores, which form compact cones (e.g., Equisetum).

Pteropsida

• The plant body is fully differentiated into root, stem, and leaves, indicating that it is progressing towards higher vascular plants.
• The leaves are also advanced, being megaphyllous (huge) and pinnately complex.
• Sporangia form on the ventral surface of sporophylls and are generally clumped together to form sori (e.g., Dryopteris, Pteris, Pteridium, Polypodium etc.)

Life Cycle of Pteridophytes

Pteridophytes have generations that alternate. Their life cycle is similar to that of seed-bearing plants, however unlike mosses and seed plants, pteridophytes have separate and free-living generations of haploid gametophyte and diploid sporophyte. The sexuality of pteridophyta gametophytes is divided into three categories:

1. Dioicous: Each gametophyte is either a male or a female, generating antheridia and sperm or archegonia and egg cells.
2. Monoicous: One gametophyte can generate both antheridia and archegonia, and can function as both a male and a female.
3. Antheridia: Matures before the archegonia in a protandrous situation.
4. Archegonia: Matures before the antheridia in a protogynous state.

Phylum

In biological taxonomy, Phylum is a taxonomic rank below Kingdom and above Class, notably for animals. Division is the corresponding rank in plants. Class Mammalia (mammals), Class Aves (birds), Class Ascidiacea (sea squirts), and so on are all members of the Phylum Chordata.

Classification of Phylum

The animal kingdom’s several phyla are as follows:

1. Porifera
2. Coelenterata (Cnidaria)
3. Platyhelminthes
4. Nematoda
5. Annelida
6. Arthropoda
7. Mollusca
8. Echinodermata
9. Hemichordata
10. Chordata

Conclusion

Pteridophyta is one of the Plant Kingdom’s oldest families of plants. They evolved far earlier than angiosperms. They were among the first “real” plants to adapt to land life.

Pteridophytes have the following primary characteristics: They are vascular, seedless plants with full generational alternation. The sporophyte also possesses real roots, stalks, and leaves. Spores, which are produced in sporangia, are used to replicate. It’s possible that they’re homosporous or heterosporous.