Rhizome creeping or shortly erect, clothed with hairs or scales. Stipe erect, mostly narrowly winged towards apex. Fronds dimorphic, simple, forked or flabellately dichotomous; vernation circinate. Sporangia large, sessile, obovoid or pyriform, arranged in 2–4 rows on modified sessile or shortly pedicellate comb-like fertile lamina, without indusium; annulus terminal, cap-like; spores many. Gametophyte green, filamentous or cordate, growing in association with fungus.
Cosmopolitan, with 4 genera and c. 15 species.
Source:
Entwisle, T.J. (1994). Ferns and allied plants (Psilophyta, Lycopodiophyta, Polypodiophyta). In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 2, Ferns and Allied Plants, Conifers and Monocotyledons, pp. 13–111. Inkata Press, Melbourne.