FAMILY CHARACTERISTICS

EUSPORANGIATE PTERIDOPHYTES

PSILOPHYTA

PSILOTACEAE -- Whisk fern family

*True roots and leaves absent

Leaf-like scales present

Homosporous

*Sporangia 3-parted, borne in scale axils

*Stems branching dichotomously

Psilotum & Tmesipteris only two genera (tropical)

LYCOPODIOPHYTA

LYCOPODIACEAE -- Clubmoss family

*True leaves present, spirally-arranged

Stems usually branching dichotomously

*Sporangia adaxial on the sporophylls

Homosporous

Lycopodium, Lycopodeiella, Diphasiastrum Huperzia

SELAGINELLACEAE -- Selaginella family

*true leaves present, spirally arranged on stem

stems branching dichotomously

*Sporangia adaxial on the sporopyylls

*Heterosporous

Selaginella

ISOETACEAE -- Quillwort family

*stems short, erect, cormlike with secondary growth

*leaves long, quill-like,

*sporangia axillary, large, sunken in base of leaf

Isoetes

EQUISETOPHYTA

EQUISETACEAE -- Horsetail family

*True leaves present, scale like

*Stems jointed

*Branches and leaves whorled

Homosporous

*Sporangia borne in terminal strobilus

Spores have elaters

Equisetum

POLYPODIOPHYTA

EUSPORANGIATE FERN FAMILIES

OPHIOGLOSSACEAE

Short fleshy uprright stem

*Vernation noncircinate to weakly circinate

*Fertile spike attached to leaf blade and petiole junction

*Roots completely without root hair

*Gametophyte fleshy, subterranean, with endophytic fungus

Ophioglossum, Botrychium

LEPTOSPORANGIATE FERN FAMILIES

OSMUNDACEAE Royal Fern, Cinnamon and Interrupted Ferns

*Fronds wholly or partially dimorphic

*Mostly occurring in marshes and swamps

Stout rhizome, often with persistent stipe bases

*Osmunda (3spp)

PTERIDACEAE Maidenhair, Cloak and Lip Ferns

Generally small ferns of unique habitats

Rhizomes short-creeping

*Sori borne along the recurved leaf margins

Stipe thin and wiry

Adiantum, Cheilanthes, Pellaea (2spp)

POLYPODIACEAE Polypody Ferns

Rhizome creeping, scaly

*Epiphytes on trees or rocks, in moist environment

Blade pinnatifid

*Sori medial, round, indusium lacking

Polypodium Pleopeltis

DENNSTAEDIACEAE Hayscented, Bracken Ferns

Sori marginal

*Fronds large and bipinnate to tripinnate

Open woods and meadows, weedy

Dennstaedtia, Pteridium

ASPLENIACEAE Spleenworts

*Sori round to elongate

Indusium absent

Fronds of firm or leathery texture, entire to bipinnate

Asplenium (6 spp)

DRYOPTERIDIACEAE Wood Ferns, Sensitive and Cliff Ferns

Sori mostly away from leaf margin (except Dryopteris marginalis)

Indusium linear to round, attached centrally, laterally or absent

Athyrium, Cystopteris (5 spp), Deparia, Diplazium, Dryopteris(7spp), Matteuccia, Onoclea, Polystichum, ,

Woodisa

THELYPTERIDIACEAE Marsh Fern Family

Indusium reniform and attached laterally or absent

Sori well defined on undersurface, on veins away from margins

Thelypteris (2spp), Phegopteris (2 spp)

BLECHNACEAE Chain Fern

*Sori originating in areoles along midveins

Indusium present

Pinnae pinnatifid

*Acidic bogs and swamps

Woodwardia

AZOLLACEAE Mosquito Fern

*Small feather-like floating aquatic plants

Minute leaves, borne in two rows

*Heterosporous

Harboring nitrogen-fixing cyanobacteria in leaf cavities

Azolla

HYMENOPHYLLACEAE Filmy Fern

*Rare, moist noncalcareous rock crevices

*Fronds translucent, one cell thick, Sori marginal in pockets

Trichomanes

SCHIZAEACEAE

Sporangia with an apical annulus

*Palmately lobed leaflets

*Climbing nature due to indeterminate growth pattern of rachis

Lygodium