Pteropsida Flashcards
What is the common name for Pteropsida?
Ferns
What groups are the Pteropsida divided into?
Eusporangium
Leptosporangium
What groups are within the Eusporangia?
Moonworts
Whisk ferns
Horsetails
Marattiales
What Leptosporangiate ferns are native to the UK?
Osmundaceae
Hymenophyllaceae
Polypodiales
What features define the Horsetails (Equisetaceae)?
Jointed stems Whorled branches Leaves highly reduced Sporangia in rings around central axis to make cone Spores have elaters for dispersal
Describe the feautures of Leptosporangiate ferns.
Frond is aerial part of fern, divided into blade and stipe
Lower part of fern is rhizome
Cicinate venation - coiled into crosiers
Sorus - aggregation of sporangia, usually on underside of frond, indusium - flap like covering
Describe the Sporangium of Leptosporangiate ferns.
Sporangium wall 1 cell thick
Composed of annulus and stalk
Dispersal acts like spring - drying causes spine to reflex, further drying causes snap back into position
What is the common name for Osmundaceae?
Royal ferns
Describe the Osmundaceae.
Fronds heteromorphic
2 pinnate
What is the common name of the Hymenophyllaceae?
Filmy ferns
Describe the Hymenophyllaceae.
Fronds translucent
What are the UK native families of Polypodiales?
Dennstaedtiaceae - Pteridium (sori submarginal, linear, frond margin recurved)
Pteridaceae - Cryptogramma, Anogramma, Adiantum
Aspleniineae: frond with 2 vascular bundles
Cystopteridaceae
Aspleniaceae - sori linear
Woodsiaceae
Blechnaceae - Fronds heteromorphic
Athyriaceae - sori J shaped
Thelypteridaceae
Polypodiineae: frond with vascular bundles in U shaped arch
Dryopteridaceae - stems scaly, indusium present
Polypodiaceae - sori circular/oblong, no indusium
Describe the Dennstaedtiaceae (bracken).
Frond 3 pinnate
Sori submarginal
No indusium
Margin recurved
Describe the Blechnaceae (hard fern).
Fronds heteromorphic
1 pinnate/ pinnatifid
Describe the Dryopteridaceae.
Fronds 1-3 pinnate
Scaly at least at base
Sori near midvein, shield or kidney shaped
Indusium present