CLASSIFICATION OF PTERIDOPHYTES
• According to the older taxonomists, vascular cryptogams in to two divisions: Pteridophyta and Spermatophyta.
• With the discovery of some fern like, seed bearing fossil plants the distinction between the two divisions Pteridophyta and Spermatophyta has been eliminated.
• All the vascular plants are placed in a single division, Tracheophyta. Now the plant kingdom includes, only three divisions – Thallophyta, Bryophyta and Tracheophyta.
• Eams divided the vascular plants or tracheophyta in to four main groups. Psilopsida, Lycopsida, Sphenopsida and Pteropsida.
a. Psilopsida includes Psilophytales and Psilotales.
b. Lycopsida includes Lycopodiales, Selaginellales, Lepidodendrales, Isoetales.
c. Sphenopsida includes Hyeniales, Sphenophyllales and Equisetales.
d. Pteropsida includes Filicineae, Gymnosperamae, Angiospermae.
• Tippo in his classification of Vascular plants gives “Tracheophyta”, the rank of phylum, which is subdivided into four subphyla: Psilopsida, Lycopsida, Sphenopsida and Pteropsida.
• In accordance with the International Code of Nomenclature Wardlaw suggested the rank of subdivisions for the four groups. According to the recommendations of ICBN, the name of the division should end in the suffix-Phyta, of a sub division in Phytina and of a class in opsida. On this basis, Smith divided the vascular cryptogams into four divisions – Psilophyta, Lepidophyta, Calamophyta and Pterophyta.
• According to Bierhorst, taxon subdivision has been deleted and redivided the division Tracheophyta into 14 classes.
• Sporne proposed the following classificatio for the vascular cryptogams. He recognised six classes in pteridophytes.
• Class A: Psilopsida
Orders: Rhyniales
Trimerophytales
Zosterophyllales
• Class B: Psilotopsida
Order: Psilotales
• Class C: Lycopsida
Orders: Protolepidodendrales
Lycopodiales
Lepidodendrales
Isoetales
Selaginellales
• Class D: Sphenopsida
Orders: Hyeniales
Sphenophyllales
Calamitales
Equisetales
• Class E: Pteropsida:
Sub-class: Primofilices
Orders: Cladoxylales
Coenopteridales
Sub-class: Eusporangiate
Orders: Marattiales
Ophioglossales
Sub-class: Osmundidae
Order: Osmundales
Sub-class: Leptosporangiatae
Order: Filicales
Marseliales
Salviniales
(f) Class F: Progymnospermopsida
Orders: Aneurophytales
Protopityales
Archaeopteridales
• According to the older taxonomists, vascular cryptogams in to two divisions: Pteridophyta and Spermatophyta.
• With the discovery of some fern like, seed bearing fossil plants the distinction between the two divisions Pteridophyta and Spermatophyta has been eliminated.
• All the vascular plants are placed in a single division, Tracheophyta. Now the plant kingdom includes, only three divisions – Thallophyta, Bryophyta and Tracheophyta.
• Eams divided the vascular plants or tracheophyta in to four main groups. Psilopsida, Lycopsida, Sphenopsida and Pteropsida.
a. Psilopsida includes Psilophytales and Psilotales.
b. Lycopsida includes Lycopodiales, Selaginellales, Lepidodendrales, Isoetales.
c. Sphenopsida includes Hyeniales, Sphenophyllales and Equisetales.
d. Pteropsida includes Filicineae, Gymnosperamae, Angiospermae.
• Tippo in his classification of Vascular plants gives “Tracheophyta”, the rank of phylum, which is subdivided into four subphyla: Psilopsida, Lycopsida, Sphenopsida and Pteropsida.
• In accordance with the International Code of Nomenclature Wardlaw suggested the rank of subdivisions for the four groups. According to the recommendations of ICBN, the name of the division should end in the suffix-Phyta, of a sub division in Phytina and of a class in opsida. On this basis, Smith divided the vascular cryptogams into four divisions – Psilophyta, Lepidophyta, Calamophyta and Pterophyta.
• According to Bierhorst, taxon subdivision has been deleted and redivided the division Tracheophyta into 14 classes.
• Sporne proposed the following classificatio for the vascular cryptogams. He recognised six classes in pteridophytes.
• Class A: Psilopsida
Orders: Rhyniales
Trimerophytales
Zosterophyllales
• Class B: Psilotopsida
Order: Psilotales
• Class C: Lycopsida
Orders: Protolepidodendrales
Lycopodiales
Lepidodendrales
Isoetales
Selaginellales
• Class D: Sphenopsida
Orders: Hyeniales
Sphenophyllales
Calamitales
Equisetales
• Class E: Pteropsida:
Sub-class: Primofilices
Orders: Cladoxylales
Coenopteridales
Sub-class: Eusporangiate
Orders: Marattiales
Ophioglossales
Sub-class: Osmundidae
Order: Osmundales
Sub-class: Leptosporangiatae
Order: Filicales
Marseliales
Salviniales
(f) Class F: Progymnospermopsida
Orders: Aneurophytales
Protopityales
Archaeopteridales
Very usefull 👍
ReplyDelete