Davalliaceae

Abstract

Epiphytic, less often epilithic or terrestrial ferns with short- to long-creeping, fleshy stem; cortex little sclerotic; stele a peculiar type of strongly dorsiventral dictyostele, only some perforations associated with leaf traces. Stem densely and permanently clothed in scales with often cordate or peltate base, the scales often toothed, sometimes clathrate; surface and/or margin of scales bearing hairs, these glandular or not; rarely hairs on stem beside scales. Roots mostly ventral. Leaves inserted in two alternate rows on the dorsal side of the stem, on short phyllopodia, with a functional articulation at the base of the petiole. Petiole ± sclerotic, with two lateral, almost continuous pneumatophores, with two large adaxial and a varying number of smaller abaxial bundles (in some species only one or none), all together forming a U or a semi-circle; petiole usually long, stramineous to brown, adaxially flattened or more often with a groove, this continuous with the grooves on the axes of higher order, the middle of the groove usually raised, ridge-like.