Greek hypo, below, + lepis, scale, alluding to the reflexed lobes that produce "scalelike" false indusia found in many species in this genus.

Plants medium-sized to large (rarely small), terrestrial. Rhizomes long-creeping, hairy. Fronds remote. Stipes adaxially grooved, sparsely hairy to glabrous, cross sections at base revealing U-shaped vascular bundles. Blades 2 to several times pinnate, often large, often with multicellular hairs, tips often growing intermittently after a resting phase; rachises like stipes, bearing septate hairs, grooves continuous with grooves of pinna rachises. Sori marginal and protected by reflexed lobes of segments, or submarginal and unprotected, round, on vein endings. Indusia absent.

A poorly understood tropical and temperate genus of about forty species, represented in Hawai 'i by a single endemic species with two varieties.