Large, tough-fronded terrestrial ferns. Rhizomes creeping, short, thick, more or less erect, branching sparse, covered with scales. Sterile and fertile fronds similar. Fronds in clusters, broadly ovate in outline. Blades divided twice, leathery, dark green, evergreen; veins netted. Plantlets produced on the fronds of some species. Stalks thick. Sori sunken, in single row each side of the midrib of each segment. Indusia thick, elongated to almost square, flap-like, opening towards the midrib.

10 species from the Northern Hemisphere.

Plantlets and spores.

Veins netted; sori separate, sunken and with a chain-like appearance (hence the common name).

Source: Spencer, R. (1995). Blechnaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 1, Ferns, conifers & their allies. The identification of garden and cultivated plants. University of New South Wales Press.