The following is a checklist of all the pteridophytes that have been recorded on the Island. The families are arranged in the sequence described by M. Hill & C. Preston in BSBI News, 91, September 2002. Within the families the genera and species follow the sequence used in C. Stace’s New Flora of the British Isles, except that Phyllitis scolopendrium and Ceterach officinarum are retained in Asplenium as per Pinter et al. (2002).

Also following discussions with Christopher Fraser-Jenkins, who has kindly sent me a draft copy of his new paper on the D. affinis group, the former subspecies of D. affinis are now raised to species level.

Class LYCOPODIOPSIDA

Lycopodiales
        Lycopodiaceae
               Huperzia
                       Huperzia selago
               Lycopodiella
                      Lycopodiella inundata
               Lycopodium
                       Lycopodium clavatum
                       Lycopodium annotinum
               Diphasiastrum
                       Diphasiastrum alpinum
Selaginales
        Selaginellaceae
               Selaginella
                       Selaginella selaginoides
Isoetales
        Isoetaceae
               Isoetes
                       Isoetes lacustris
                       Isoetes echinospora

Class POLYPODIOPSIDA
Subclass Ophioglossidae
Ophioglossiales
        Ophioglossaceae
                Ophioglossum
                      Ophioglossum vulgatum
                Botrychium
                      Botrychium lunaria

Subclass Equisetidae
Equisetales
        Equisetaceae
               Equisetum
                       Equisetum hyemale
                       E. hyemale x E. variegatum = E. x trachyodon
                       Equisetum variegatum
                       Equisetum fluviatile
                       E. fluviatile x E. palustre = E. x dycei
                       E. fluviatile x E. arvense = E. x litorale
                       Equisetum arvense
                       E. arvense x E. palustre = E. x rothmaleri
                       Equisetum pratense
                       Equisetum sylvaticum
                       Equisetum palustre
                       E. palustre x E. telmateia = E. x font-queri
                       Equisetum telmateia

Subclass Polypodiidae
Hymenophyllales
        Hymenophyllaceae
               Hymenophyllum
                       Hymenophyllum tunbrigense
                       Hymeophyllum wilsonii
               Trichomanes
                       Trichomanes speciosum
Osmundales
        Osmundaceae
               Osmunda regalis
Marsileales
        Marsileaceae
               Pilularia
                       Pilularia globulifera
Polypodiales
        Adiantaceae
               Cryptogramma
                       Cryptogramma crispa
        Dennstaedtiaceae
               Pteridium
                       Pteridium aquilinum
        Blechnaceae
               Blechnum
                       Blechnum spicant
        Aspleniaceae
               Asplenium
                       Asplenium marinum
                       Asplenium trichomanes
                       Asplenium viride
                       Asplenium adiantum-nigrum
                       Asplenium ruta-muraria
                       Asplenium ceterach
                       Asplenium scolopendrium
        Dryopteridaceae
               Polystichum
                       Polystichum setiferum
                       Polystichum lonchitis
                       Polystichum aculeatum
                       P. aculeatum x P. setiferum = P. x bicknellii
               Dryopteris
                       Dryopteris filix-mas
                       Dryopteris affinis
                       Dryopteris borreri
                       Dryopteris cambrensis
                       Dryopteris oreades
                       Dryopteris dilatata
                       Dryopteris expansa
                       Dryopteris aemula
                       Dryopteris carthusiana
                       D. affinis x D. filix-mas = D. complexa
                       D. cambrensis x D. filix-mas = D. x convoluta
                       D. borreri x D. filix-mas = D. x critica
        Thelpteridaceae
               Oreopteris
                       Oreopteris limbosperma
               Phegopteris
                       Phegopteris connectilis
        Woodsiaceae
               Athyrium
                       Athyrium filix-femina
               Cystopteris
                       Cystopteris fragilis
                       Cystopteris montana
               Woodsia
                       Woodsia alpina
               Gymnocarpium
                       Gymnocarpium dryopteris
        Polypodiaceae
               Polypodium
                       Polypodium vulgare
                       Polypodium interjectum
                       P. interjectum x P. vulgare = P. mantoniae