Plants evergreen, terrestrial or epilithic, medium-sized, Rhizome creeping or subscandent, protostelic, rarely branching, covered with long, uniseriate, pale brown, multicellular hairs; scales absent. Fronds dimorphic; stipes ± approximate, hairy at base only, non-articulate. Sterile lamina subleathery, entire or lobed, rarely to 4-lobed; main veins dichotomously forked with anadromous branching, smaller veins areolate with smaller areoles included in larger ones and numerous free included ultimate veinlets, all veins ± prominent; stomata paracytic. Fertile lamina simple, long, narrow, with 3 longitudinal main veins, abaxially almost wholly covered with sporangia. Sporangia of mixed maturation, intermingled with hairlike paraphyses with swollen terminal cell; spores ca. 128 per sporangium, trilete, tetrahedral, with prominent ridge near aperture, surface smooth to rugulose. x = 33.
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Fronds dimorphous; fertile fronds narrow, acrostichoid
Characters of the family.